This work was supported by the research grant from the National Research Foundation of Korea (Grant number: 2017M2A2A6A01070858).

1. Synthesis of Citrate-Stabilized Gold Nanoparticles
<ol>
	<li>Wash a two-neck round-bottom flask (250 mL) and a magnetic stir bar with aqua regia, a mixture of concentrated hydrochloric acid and concentrated nitric acid in a 3:1 volume ratio. 
	CAUTION: Aqua regia solution is extremely corrosive and may result in explosion or skin burns if not handled with extreme caution.</li>
	<li>Rinse the glassware thoroughly with deionized water to remove residual aqueous acid.</li>
	<li>Add 120 mL of chloroauric acid solution (HAuCl4, 1 mM) to the two-neck round-bottom flask (250 mL) and heat it to reflux under constant stirring.</li>
	<li>Add 12 mL of sodium citrate tribasic (35 mM) solution quickly to the two-neck round-bottom flask and reflux the resulting mixture for another 20 min for the complete reduction of the gold salt.</li>
	<li>Allow the colloidal suspension of nanoparticles (deep red) to cool down to room temperature.</li>
	<li>Measure the concentration of the gold nanoparticles (AuNPs) with UV-vis spectroscopy at a wavelength of 520 nm (extinction coefficient of 2.8 x 108) using a quartz cuvette (1 cm path length).</li>
	<li>Add a single drop of AuNPs suspension onto a carbon-coated copper grid (400 mesh) and dry it at room temperature. Measure the size of AuNPs with transmission electron microscopy (TEM).</li>
	<li>Keep the colloidal gold nanoparticle suspension at 4 &#176;C.</li>
</ol>
2. Preparation of Hybrid Membrane (Au-CAM)
<ol>
	<li>Preparation of gold nanoparticles-embedded membrane filter using a syringe unit
	<ol>
		<li>Wash a cellulose acetate membrane (pore size: 0.45 &#956;m, diameter: 25 mm) supported by a filter unit with deionized water (10 mL) for three times.</li>
		<li>Withdraw 10 mL of citrate-stabilized AuNPs (10 nM) with a sterile syringe (20 mL) and add it slowly into a pre-washed cellulose acetate membrane filter (Figure 1).</li>
		<li>Wash the filter unit with 10 mL of deionized water three times to remove non-immobilized AuNPs. 
		&#8203;NOTE: AuNPs immobilized on the cellulose acetate membrane are highly stable, and thus Au-CAM can be stored under ambient condition for several weeks without the loss of their chemical properties or stability.</li>
	</ol>
	</li>
	<li>Preparation of gold nanoparticle membrane filter by the vacuum pump
	<ol>
		<li>Place the cellulose acetate membrane (pore size: 0.45 &#956;m, diameter: 47 mm) between a filter holder fritted glass support (diameter: 40 mm) and a graduated funnel (300 mL).</li>
		<li>Connect a combined unit of the fritted glass support and graduated funnel to a recover flask (500 mL) and a vacuum pump.</li>
		<li>Add 10 mL of citrate-stabilized AuNPs (10 nM) into the graduated funnel and then apply vacuum until all AuNPs are passed through the cellulose acetate membrane (approximately 20 s).</li>
		<li>Repeat the same procedure (step 2.2.3) on the other side of the membrane to immobilize AuNPs on both sides of the membrane.</li>
		<li>Analyze the surface of Au-CAM using scanning electron microscope (SEM) under the high-performance conditions with the accelerating voltages up to 15 kV (Figure 2d). 
		NOTE: To check the stability of nanoparticles on Au-CAM in a high salt condition, the composite membrane was immersed in 1.0 M NaCl solution for 2 h and then visual inspection was performed to confirm the stability of the Au-CAM.</li>
	</ol>
	</li>
</ol>
3. Adsorption of Radioactive Iodine Using Au-CAM in a Batch System
<ol>
	<li>Dilute the radioactive iodine ([125I]NaI, 2.2 MBq) in 3 mL of pure water, 1.0 M NaCl, or 10 nM NaI and add each solution into a Petri dish (50 mm diameter &#215; 15 mm height). 
	CAUTION: The oxidized radioactive iodine can be volatile and must be handled with adequate lead shields and lead vials. All radiochemical steps should be performed in a well-ventilated charcoal-filtered hood, and the experimental procedures need to be monitored by radioactivity detectors.</li>
	<li>Place the Au-CAM which is prepared by using a vacuum filter into radioactive iodine solutions and shake them gently at room temperature.</li>
	<li>Withdraw 10 &#956;L of the radioactive iodine solution from the Petri dish at given time points (0, 5, 10, 30, 60, 120 min) and measure the radioactivity of the aliquot using automatic &#947;-counter.</li>
	<li>Rinse the Au-CAM with purified water after 120 min and then measure the amount of radioactivity captured on the membrane using automatic &#947;-counter (Figure 3).</li>
</ol>
4. Desalination of Radioactive Iodine under Continuous In-Flow Condition
<ol>
	<li>Removal of radioactive iodine anions (125I-) using an Au-CAM filter
	<ol>
		<li>Dissolve the radioactive iodine (3.7 MBq) in 50 mL of pure water, PBS 1x, 1.0 M NaCl, 0.1 M NaOH, 0.1 M HCl, 10 mM CsCl, 10 mM SrCl2, synthetic urine, or sea water.</li>
		<li>Withdraw 50 mL of each solution with a sterile syringe (50 mL) and pass through the Au-CAM filter unit at an in-flow rate of about 1.5 mL/s using a syringe pump (Figure 1).</li>
		<li>Transfer 5 mL of the filtrate into a plastic vial for quantifying the radioactivity in the solution.</li>
		<li>Measure the amount of residual radioactivity in the filtrate solution using automatic &#947;-counter (Figure 4).</li>
	</ol>
	</li>
	<li>Reusability test of Au-CAM filter
	<ol>
		<li>Dissolve the radioactive iodine in a synthetic urine or seawater (3.7 MBq/50 mL).</li>
		<li>Withdraw 50 mL of solution with a sterile syringe (50 mL) and add it into the Au-CAM filter unit at an in-flow rate of about 1.5 mL/s using a syringe pump.</li>
		<li>Repeat the same filtration procedure (step 4.2.2) for seven times using a single Au-CAM filter unit.</li>
		<li>Transfer 5 mL of the filtrate into a plastic vial for quantifying the radioactivity in the solution.</li>
		<li>Measure the amount of radioactivity in seven filtrate solutions by using automatic &#947;-counter.</li>
	</ol>
	</li>
</ol>

<ol>
	<li>Ojovan, M. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Handbook of Advanced Radioactive Waste Conditioning Technologies. , (2011).</li><li>Abdel Rahman, R. O., Ibrahim, H. A., Hung, Y. -. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Liquid+Radioactive+Wastes+Treatment:+A+Review.">Liquid Radioactive Wastes Treatment: A Review.</a> Water. 3, 551-565 (2011).</li><li>Khayet, M., Matsuura, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Radioactive+decontamination+of+water.">Radioactive decontamination of water.</a> Desalination. 321, 1-2 (2013).</li><li>McLaughlin, P. D., Jones, B., Maher, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+update+on+radioactive+release+and+exposures+after+the+Fukushima+Dai-ichi+nuclear+disaster.">An update on radioactive release and exposures after the Fukushima Dai-ichi nuclear disaster.</a> The British Journal of Radiolog. 85, 1222-1225 (2012).</li><li>Chernobyl Forum Expert Group 'Environment'. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Environmental+Consequences+of+the+Chernobyl+Accident+and+their+Remediation:+Twenty+Years+of+Experience.">Environmental Consequences of the Chernobyl Accident and their Remediation: Twenty Years of Experience.</a> International Atomic Energy Agency. , (2006).</li><li>Hou, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Iodine-129+in+seawater+offshore+Fukushima:+distribution,+inorganic+speciation,+sources,+and+budget.">Iodine-129 in seawater offshore Fukushima: distribution, inorganic speciation, sources, and budget.</a> Environmental Science &amp; Technology. 47, 3091-3098 (2013).</li><li>Mu, W., Yu, Q., Li, X., Wei, H., Jian, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adsorption+of+radioactive+iodine+on+surfactant-modified+sodium+niobate.">Adsorption of radioactive iodine on surfactant-modified sodium niobate.</a> RSC Advances. 6, 81719-81725 (2016).</li><li>Yang, D., Liu, H., Liu, L., Sarina, S., Zheng, Z., Zhu, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Silver+oxide+nanocrystals+anchored+on+titanate+nanotubes+and+nanofibers:+promising+candidates+for+entrapment+of+radioactive+iodine+anions.">Silver oxide nanocrystals anchored on titanate nanotubes and nanofibers: promising candidates for entrapment of radioactive iodine anions.</a> Nanoscale. 5, 11011-11018 (2013).</li><li>Yang, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Capture+of+radioactive+cesium+and+iodide+ions+from+water+by+using+titanate+nanofibers+and+nanotubes.">Capture of radioactive cesium and iodide ions from water by using titanate nanofibers and nanotubes.</a> Angewandte Chemie International Edition. 50, 10594-10598 (2011).</li><li>Cheng, Q., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adsorption+of+gaseous+radioactive+iodine+by+Ag/13X+zeolite+at+high+temperatures.">Adsorption of gaseous radioactive iodine by Ag/13X zeolite at high temperatures.</a> Journal of Radioanalytical and Nuclear Chemistry. 303, 1883-1889 (2015).</li><li>Bennett, T. D., Saines, P. J., Keen, D. A., -C, T. a. n. J., Cheetham, A. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ball-Milling-Induced+Amorphization+of+Zeolitic+Imidazolate+Frameworks+(ZIFs)+for+the+Irreversible+Trapping+of+Iodine.">Ball-Milling-Induced Amorphization of Zeolitic Imidazolate Frameworks (ZIFs) for the Irreversible Trapping of Iodine.</a> Chemistry - A European Journal. 19, 7049-7055 (2013).</li><li>Huang, P. S., Kuo, C. H., Hsieh, C. C., Horng, Y. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selective+capture+of+volatile+iodine+using+amorphous+molecular+organic+solids.">Selective capture of volatile iodine using amorphous molecular organic solids.</a> Chemical Communications. 48, 3227-3229 (2012).</li><li>Chapman, K. W., Chupas, P. J., Nenoff, T. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Radioactive+Iodine+Capture+in+Silver-Containing+Mordenites+through+Nanoscale+Silver+Iodide+Formation.">Radioactive Iodine Capture in Silver-Containing Mordenites through Nanoscale Silver Iodide Formation.</a> Journal of the American Chemical Society. 132, 8897-8899 (2010).</li><li>Watanabe, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Novel+Long-Term+Immobilization+Method+for+Radioactive+Iodine-129+Using+a+Zeolite/Apatite+Composite+Sintered+Body.">Novel Long-Term Immobilization Method for Radioactive Iodine-129 Using a Zeolite/Apatite Composite Sintered Body.</a> ACS Applied Materials &amp; Interfaces. 1, 1579-1584 (2009).</li><li>Massasso, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+iodine+adsorption+within+Hofmann-type+structures+M(L)[M'(CN)4]+(M+=+Ni,+Co;+M'+=+Ni,+Pd,+Pt):+impact+of+their+composition.">Molecular iodine adsorption within Hofmann-type structures M(L)[M'(CN)4] (M = Ni, Co; M' = Ni, Pd, Pt): impact of their composition.</a> Dalton Transactions. 44, 19357-19369 (2015).</li><li>Falaise, C., Volkringer, C., Facqueur, J., Bousquet, T., Gasnot, L., Loiseau, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Capture+of+iodine+in+highly+stable+metal-organic+frameworks:+a+systematic+study.">Capture of iodine in highly stable metal-organic frameworks: a systematic study.</a> Chemical Communications. 49, 10320-10322 (2013).</li><li>Sava, D. F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Capture+of+Volatile+Iodine,+a+Gaseous+Fission+Product,+by+Zeolitic+Imidazolate+Framework-8.">Capture of Volatile Iodine, a Gaseous Fission Product, by Zeolitic Imidazolate Framework-8.</a> Journal of the American Chemical Society. 133, 12398-12401 (2011).</li><li>Zhang, Z. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+type+of+polyhedron-based+metal-organic+frameworks+with+interpenetrating+cationic+and+anionic+nets+demonstrating+ion+exchange,+adsorption+and+luminescent+properties.">A new type of polyhedron-based metal-organic frameworks with interpenetrating cationic and anionic nets demonstrating ion exchange, adsorption and luminescent properties.</a> Chemical Communications. 47, 6425-6427 (2011).</li><li>Li, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Highly+efficient+I2+capture+by+simple+and+low-cost+deep+eutectic+solvents.">Highly efficient I2 capture by simple and low-cost deep eutectic solvents.</a> Green Chemistry. 18, 2522-2527 (2016).</li><li>Yan, C., Mu, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Investigation+of+ionic+liquids+for+efficient+removal+and+reliable+storage+of+radioactive+iodine:+a+halogen-bonding+case.">Investigation of ionic liquids for efficient removal and reliable storage of radioactive iodine: a halogen-bonding case.</a> Physical Chemistry Chemical Physics. 16, 5071-5075 (2014).</li><li>Choi, M. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficient+bioremediation+of+radioactive+iodine+using+biogenic+gold+nanomaterial-containing+radiation-resistant+bacterium,+Deinococcus+radiodurans+R1.">Efficient bioremediation of radioactive iodine using biogenic gold nanomaterial-containing radiation-resistant bacterium, Deinococcus radiodurans R1.</a> Chemical Communications. 53, 3937-3940 (2017).</li><li>Kim, Y. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tumor+targeting+and+imaging+using+cyclic+RGD-PEGylated+gold+nanoparticle+probes+with+directly+conjugated+iodine-125.">Tumor targeting and imaging using cyclic RGD-PEGylated gold nanoparticle probes with directly conjugated iodine-125.</a> Small. 7, 2052-2060 (2011).</li><li>Choi, M. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gold-Nanoparticle-Immobilized+Desalting+Columns+for+Highly+Efficient+and+Specific+Removal+of+Radioactive+Iodine+in+Aqueous+Media.">Gold-Nanoparticle-Immobilized Desalting Columns for Highly Efficient and Specific Removal of Radioactive Iodine in Aqueous Media.</a> ACS Applied Materials &amp; Interfaces. 8, 29227-29231 (2016).</li><li>Mushtaq, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficient+and+selective+removal+of+radioactive+iodine+anions+using+engineered+nanocomposite+membranes.">Efficient and selective removal of radioactive iodine anions using engineered nanocomposite membranes.</a> Environmental Science: Nano. 4, 2157-2163 (2017).</li><li>Awual, M. R., Ismael, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficient+gold(III)+detection,+separation+and+recovery+from+urban+mining+waste+using+a+facial+conjugate+adsorbent.">Efficient gold(III) detection, separation and recovery from urban mining waste using a facial conjugate adsorbent.</a> Sensors and Actuators B: Chemical. 196, 457-466 (2014).</li><li>Awual, M. R., Hasan, M. M., Naushad, M., Shiwaku, H., Yaita, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparation+of+new+class+composite+adsorbent+for+enhanced+palladium(II)+detection+and+recovery.">Preparation of new class composite adsorbent for enhanced palladium(II) detection and recovery.</a> Sensors and Actuators B: Chemical. 209, 790-797 (2015).</li><li>Awual, M. R., Hasan, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fine-tuning+mesoporous+adsorbent+for+simultaneous+ultra-trace+palladium(II)+detection,+separation+and+recovery.">Fine-tuning mesoporous adsorbent for simultaneous ultra-trace palladium(II) detection, separation and recovery.</a> Journal of Industrial and Engineering Chemistry. 21, 507-515 (2015).</li><li>Awual, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ring+size+dependent+crown+ether+based+mesoporous+adsorbent+for+high+cesium+adsorption+from+wastewater.">Ring size dependent crown ether based mesoporous adsorbent for high cesium adsorption from wastewater.</a> Chemical Engineering Journal. 303, 539-546 (2016).</li><li>Awual, M. R., Miyazaki, Y., Taguchi, T., Shiwaku, H., Yaita, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Encapsulation+of+cesium+from+contaminated+water+with+highly+selective+facial+organic-inorganic+mesoporous+hybrid+adsorbent.">Encapsulation of cesium from contaminated water with highly selective facial organic-inorganic mesoporous hybrid adsorbent.</a> Chemical Engineering Journal. 291, 128-137 (2016).</li><li>Awual, M. R., Yaita, T., Taguchi, T., Shiwaku, H., Suzuki, S., Okamoto, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selective+cesium+removal+from+radioactive+liquid+waste+by+crown+ether+immobilized+new+class+conjugate+adsorbent.">Selective cesium removal from radioactive liquid waste by crown ether immobilized new class conjugate adsorbent.</a> Journal of Hazardous Materials. 278, 227-235 (2014).</li><li>Awual, M. R., Suzuki, S., Taguchi, T., Shiwaku, H., Okamoto, Y., Yaita, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Radioactive+cesium+removal+from+nuclear+wastewater+by+novel+inorganic+and+conjugate+adsorbents.">Radioactive cesium removal from nuclear wastewater by novel inorganic and conjugate adsorbents.</a> Chemical Engineering Journal. 242, 127-135 (2014).</li><li>Awual, M. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficient+detection+and+adsorption+of+cadmium+(II)+ions+using+innovative+nano-composite+materials.">Efficient detection and adsorption of cadmium (II) ions using innovative nano-composite materials.</a> Chemical Engineering Journal. 343, 118-127 (2018).</li><li>Awual, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+type+mesoporous+conjugate+material+for+selective+optical+copper(II)+ions+monitoring+&amp;+removal+from+polluted+waters.">New type mesoporous conjugate material for selective optical copper(II) ions monitoring &amp; removal from polluted waters.</a> Chemical Engineering Journal. 307, 85-94 (2017).</li><li>Awual, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Novel+nanocomposite+materials+for+efficient+and+selective+mercury+ions+capturing+from+wastewater.">Novel nanocomposite materials for efficient and selective mercury ions capturing from wastewater.</a> Chemical Engineering Journal. 307, 456-465 (2017).</li><li>Awual, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Solid+phase+sensitive+palladium(II)+ions+detection+and+recovery+using+ligand+based+efficient+conjugate+nanomaterials.">Solid phase sensitive palladium(II) ions detection and recovery using ligand based efficient conjugate nanomaterials.</a> Chemical Engineering Journal. 300, 264-272 (2016).</li><li>Awual, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assessing+of+lead(III)+capturing+from+contaminated+wastewater+using+ligand+doped+conjugate+adsorbent.">Assessing of lead(III) capturing from contaminated wastewater using ligand doped conjugate adsorbent.</a> Chemical Engineering Journal. 289, 65-73 (2016).</li><li>Awual, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+facial+composite+adsorbent+for+enhanced+copper+(II)+detection+and+removal+from+wastewater.">A novel facial composite adsorbent for enhanced copper (II) detection and removal from wastewater.</a> Chemical Engineering Journal. 266, 368-375 (2015).</li><li>Kaushik, M., Moores, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Review:+nanocelluloses+as+versatile+supports+for+metal+nanoparticles+and+their+applications+in+catalysis.">Review: nanocelluloses as versatile supports for metal nanoparticles and their applications in catalysis.</a> Green Chemistry. 18, 622-637 (2016).</li><li>Jang, H., Kim, Y. K., Ryoo, S. R., Kim, M. H., Min, D. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Facile+synthesis+of+robust+and+biocompatible+gold+nanoparticles.">Facile synthesis of robust and biocompatible gold nanoparticles.</a> Chemical Communication. 46, 583-585 (2010).</li><li>Bolisetty, S., Mezzenga, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amyloid-carbon+hybrid+membranes+for+universal+water+purification.">Amyloid-carbon hybrid membranes for universal water purification.</a> Nature Nanotechnology. 11, 365-371 (2016).</li><li>Zakrzewska-Trznadel, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Advances+in+membrane+technologies+for+the+treatment+of+liquid+radioactive+waste.">Advances in membrane technologies for the treatment of liquid radioactive waste.</a> Desalination. 321, 119-130 (2013).</li><li>Rana, D., Matsuura, T., Kassim, M. A., Ismail, A. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Radioactive+decontamination+of+water+by+membrane+processes+-+A+review.">Radioactive decontamination of water by membrane processes - A review.</a> Desalination. 321, 77-92 (2013).</li></ol>

The authors have nothing to disclose.

In recent year, various engineered nanomaterials and membranes have been developed to remove hazardous radioactive metals and heavy metals in water based on their specific functionality in adsorption techniques25,26,27,28,29,30,31,32,33,34,35,36,37. In this study, we demonstrated highly useful method for rapid and efficient separation of radioactive halogen species. By using citrate-stabilized AuNPs and a commercially available cellulose acetate membrane, Au-CAM can easily be prepared and the fabrication step is highly reproducible. As iodide anions is spontaneously chemisorbed on the surface of AuNPs, Au-CAM can be applied to the remediation of radioactive iodines in various aqueous media. Among various radioisotopes of iodine, we selected 125I- as a target element in this study because it emits a low radiation energy compared to other radioactive iodines and the decay half-life (59.5 days) is long enough to develop an optimized process. But the reactivity of 125I- is identical with other iodine isotopes, and thus this method will be utilized to remove more hazardous radioelements such as 131I- and 129I-.
In the presence of high concentration of competing anions such as phosphate, chloride, and hydroxide, the nano-hybrid membrane (Au-CAM) showed excellent desalination efficiency and good reusability. Another significant advantage is that immobilized nanoparticles on a cellulose acetate membrane is stable under high salt conditions and varied pH. It appears like that AuNPs on the membrane of carbohydrate were stabilized by oxygen atom containing functional groups including hydroxyl and carbonyl groups38,39. Thus, the hybrid membrane can be stored for several weeks without the loss of its performance and chemical stability. As shown in Figure 4, Au-CAM showed excellent removal efficiency in various aqueous media. The limitation of the present method is that Au-CAM would not be useful in organic solvent system including alcohols and dimethyl sulfoxide, because cellulose acetate is partially dissolved in these media and thus AuNPs can be released from the membrane.
There have been several reports describing the desalination of radioisotopes in contaminated water using various adsorbents including engineered membranes40,41,42. The continuous process in the present study is superior to conventionally used methods in terms of removal efficiency, ion-selectivity and reusability. Using a single Au-CAM (diameter: 25 mm), ca. 90 mL of aqueous waste can be purified in 1 min. It is anticipated that a lot of Au-CAM filters will be easily produced in a short time, because large-scale synthesis and characterization of the citrate-stabilized AuNPs were well-established. Taken together, Au-CAM will be a promising adsorbent system worth to investigate for the practical remediation of industrial and medical radioactive iodine wastes.

For several decades, huge amount of radioactive liquid wastes has been generated by medical institutes, research facilities, and nuclear reactors. These pollutants have often been a palpable threat to environment and human health1,2,3. Especially, radioactive iodine is recognized as one of the most hazardous elements from nuclear plant accidents. For example, an environmental report on the Fukushima and Chernobyl nuclear reactor demonstrated that the amount of released radioactive iodines including 131I (t1/2 = 8.02 days) and 129I (t1/2 = 15.7 million years) to the environment was larger than those of other radionuclides4,5. In particular, the exposure of these radioisotopes resulted in high uptake and enrichment in human thyroid6. Moreover, released radioactive iodines can cause severe contamination of soil, seawater and ground water owing to their high solubility in water. Therefore, a lot of remediation processes using various inorganic and organic adsorbents have been investigated to capture radioactive iodines in aqueous wastes7,8,9,10,11,12,13,14,15,16,17,18,19,20. Although extensive efforts have been devoted for the development of advanced adsorbent systems, the establishment of a decontamination method showing satisfactory performances under continuous in-flow condition was very limited. Recently, we reported a novel desalination process showing good removal efficiency, ion-selectivity, sustainability, and reusability by using hybrid nano-composite materials made of gold nanoparticle (AuNPs)21,22,23. Among them, gold nanoparticle-embedded cellulose acetate membranes (Au-CAM) facilitated highly efficient desalination of iodide ions under a continuous-flow system compared with those of existing adsorbent materials. Moreover, the whole procedure could be finished in a short time, which was another advantage for the treatment of nuclear wastes generated from post-use in medical and industrial applications. The overall goal of this manuscript is to provide a step-by-step protocol for the preparation of Au-CAM24. We also demonstrate a rapid and convenient filtration process for ion-selective capture of radioactive iodine using the engineered composite membranes. The detailed protocol in this report will offer a useful application of nanomaterials in the research field of environmental science.

<table><tbody><tr><td>Hydrochloric acid</td><td>DUKSAN</td><td>1129</td><td></td></tr><tr><td>Nitric acid&amp;nbsp;</td><td>JUNSEI</td><td>37335-1250</td><td></td></tr><tr><td>Chloroautic chloride trihydrate (HAuCl&lt;sub&gt;4&lt;/sub&gt;&amp;middot;3H&lt;sub&gt;2&lt;/sub&gt;O)</td><td>Sigma Aldrich</td><td>254169</td><td></td></tr><tr><td>Sodium citrate tribasic dihydrate</td><td>Sigma Aldrich</td><td>71402</td><td></td></tr><tr><td>[&lt;sup&gt;125&lt;/sup&gt;I]NaI&amp;nbsp;</td><td>Perkin-Elmer</td><td>NEZ033A010MC</td><td></td></tr><tr><td>Sodium chloride</td><td>Sigma Aldrich</td><td>S9888</td><td></td></tr><tr><td>Sodium iodide</td><td>Sigma Aldrich</td><td>383112</td><td></td></tr><tr><td>Sodium hydroxide</td><td>Sigma Aldrich</td><td>S5881</td><td></td></tr><tr><td>Lithium L-lactate</td><td>Sigma Aldrich</td><td>L2250</td><td>Synthetic urine</td></tr><tr><td>Citric acid</td><td>Sigma Aldrich</td><td>C1909</td><td>Synthetic urine</td></tr><tr><td>Sodium hydrogen carbonate</td><td>JUNSEI</td><td>43305-1250</td><td>Synthetic urine</td></tr><tr><td>Urea</td><td>Sigma Aldrich</td><td>U1250</td><td>Synthetic urine</td></tr><tr><td>Calcium chloride</td><td>JUNSEI</td><td>18230-0301</td><td>Synthetic urine</td></tr><tr><td>Magnesium sulfate</td><td>SAMCHUN</td><td>M0146</td><td>Synthetic urine</td></tr><tr><td>Potassium dihydrogen phosphate</td><td>JUNSEI</td><td>84185A1250</td><td>Synthetic urine</td></tr><tr><td>Dipotassium hydrogen phosphate</td><td>JUNSEI</td><td>84120-1250</td><td>Synthetic urine</td></tr><tr><td>Sodium sulfate</td><td>JUNSEI</td><td>83260-1250</td><td>Synthetic urine</td></tr><tr><td>Ammonium chloride</td><td>Sigma Aldrich</td><td>A9434</td><td>Synthetic urine</td></tr><tr><td>Sea water</td><td>Sigma Aldrich</td><td>S9148</td><td></td></tr><tr><td>1x PBS</td><td>Thermo</td><td>SH30256.01</td><td></td></tr><tr><td>Cellulose acetate membranes (pore size: 0.20 &amp;mu;m, diameter: 25 mm)</td><td>Advantec MFS</td><td>25CS045AS</td><td></td></tr><tr><td>Cellulose acetate membranes (pore size: 0.20 &amp;mu;m, diameter: 47 mm)</td><td>Advantec MFS</td><td>C045A047A</td><td></td></tr><tr><td>47 mm Glass Microanalysis Holders</td><td>Advantec MFS</td><td>KG47(311400)</td><td></td></tr><tr><td>Petri dish (50 mm diameter &amp;acute; 15 mm height)</td><td>SPL</td><td>10050</td><td></td></tr><tr><td>Gamma counter</td><td>Perkin-Elmer</td><td>2480 WIZARD&lt;sup&gt;2&lt;/sup&gt;</td><td>Model number</td></tr><tr><td>UV-vis spectrophotometer</td><td>Thermo</td><td>GENESYS 10</td><td>Model number</td></tr><tr><td>Transmission electron microscopy</td><td>Hitachi</td><td>H-7650</td><td>Model number</td></tr><tr><td>Field Emission Scanning electron microscope</td><td>FEI</td><td>Verios 460L</td><td>Model number</td></tr></tbody></table>

an efficient method for selective desalination of radioactive iodine anions by using gold nanoparticles-embedded membrane filter

Here, we demonstrate a detail protocol for the preparation of nanomaterials-embedded composite membranes and its application to the efficient and ion-selective removal of radioactive iodines. By using citrate-stabilized gold nanoparticles (mean diameter: 13 nm) and cellulose acetate membranes, gold nanoparticle-embedded cellulose acetate membranes (Au-CAM) have easily been fabricated. The nano-adsorbents on Au-CAM were highly stable in the presence of high concentration of inorganic salts and organic molecules. The iodide ions in aqueous solutions could rapidly be captured by this engineered membrane. Through a filtration process using an Au-CAM containing filter unit, excellent removal efficiency (&gt;99%) as well as ion-selective desalination result was achieved in a short time. Moreover, Au-CAM provided good reusability without significant decrease of its performances. These results suggested that the present technology using the engineered hybrid membrane will be a promising process for the large-scale decontamination of radioactive iodine from liquid wastes.

We have demonstrated simple methods for the fabrication of Au-CAM using citrate-stabilized AuNPs and cellulose acetate membrane (Figure 1a). The surface of Au-CAM was observed by SEM which showed that the nanomaterials were incorporated stably on the cellulose nanofibers (Figure 2). The nanoparticles incarcerated on the membrane were sustained stably and were not released from the membrane by continual washing with aqueous solutions such as 1.0 M NaCl. The adsorption capacity of an Au-CAM was approximately 12.2 &#956;mol of iodide anion per 1 g of AuNPs24. To evaluate the desalination performance, the Au-CAM prepared by the vacuum-assisted method were immersed into aqueous solutions containing 2.2 MBq of [125I]NaI (Figure 1b). After 30 min incubation, most of the radioactive iodine (&#62;99%) in pure water and 1.0 M NaCl was captured by Au-CAM (Figure 3). On the other hand, the adsorption of radioactivity was inhibited completely in the presence of non-radioactive NaI, because the surface of AuNPs was occupied by access amount of iodide anions (127I-).
For more useful application of the current method, Au-CAM filter was applied to a continuous desalination process. The radioactive iodine solutions (3.7 MBq/50 mL) were passed through a filter unit containing Au-CAM at an in-flow rate of 1.5 mL/s (Figure 1c). The amount of the residual radioactivity in the filtrate was measured using a &#947;-counter. The removal efficiency (%) was defined by the following equation (1).
Removal efficiency (%) = (C0&#160;-&#160;Ce)/C0 x&#160;100&#160; &#160; &#160;(1)
Where C0 is the concentration of radioactive iodine before filtration step and Ce is the concentration of radioactive iodine after filtration step.
As shown in Figure 4, the concentration of radioactive iodine was decreased significantly, and the excellent efficiency was obtained through a filtration step. In particular, the desalination performance of Au-CAM was not suppressed by high concentration of inorganic salts such as sodium, cesium, and strontium and several organic substances. In all cases, the removal efficiency of Au-CAM was higher than 99.5%. Au-CAM showed high removal efficiency under neutral and basic condition (up to pH 13), however, it dropped to ca. 90% under acidic condition (pH 1). Furthermore, Au-CAM could be reusable for repetitive desalination of radioactive iodine in synthetic urine and seawater. During the consecutive filtration process, more than 99% of radioactivity in aqueous media was captured efficiently using a single Au-CAM filter unit24.
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/58105/58105fig1.jpg" /> 
Figure 1. Schematic illustration of the desalination procedure in this protocol using Au-CAM. (a) Fabrication of Au-CAM by using a syringe filter unit. (b) Adsorption of radioactive iodine in a batch system. (c) Filtration of radioactive iodine under continuous in-flow condition. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/58105/58105fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/58105/58105fig2.jpg" /> 
Figure 2.Characterization of Au-CAM. (a) A photographic image of cellulose acetate membrane (diameter 47 mm). (b) A photographic image of Au-CAM (diameter 47 mm). (c) SEM image of cellulose acetate membrane (40,000X). (d) SEM image of Au-CAM (40,000X). <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/58105/58105fig2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/58105/58105fig3.jpg" /> 
Figure 3.Time-dependent removal efficiency of radioactive iodine using Au-CAM in pure water, 1.0 M NaCl, and 10 mM NaI. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/58105/58105fig3large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/58105/58105fig4.jpg" /> 
Figure 4. Filtration of radioactive iodine anions in several aqueous solutions using Au-CAM. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/58105/58105fig4large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

Watch this Scientific Journal Video about An Efficient Method for Selective Desalination of Radioactive Iodine Anions by Using Gold Nanoparticles-Embedded Membrane Filter at JoVE.com

An Efficient Method for Selective Desalination of Radioactive Iodine Anions by Using Gold Nanoparticles-Embedded Membrane Filter

An efficient method for the rapid and ion-selective desalination of radioactive iodine in several aqueous solutions is described by using gold nanoparticles-immobilized cellulose acetate membrane filters.

Here, we demonstrate a detail protocol for the preparation of nanomaterials-embedded composite membranes and its application to the efficient and ...

an-efficient-method-for-selective-desalination-radioactive-iodine

Nanyang Technological University

Research

JoVE Journal

Engineering

7.4K Views.  Korea Atomic Energy Research Institute. Een efficiënte methode voor de snelle en ion-selectieve ontzilting van radioactief jodium in verschillende waterige oplossingen wordt beschreven met behulp van de gouden nanodeeltjes-geïmmobiliseerd celluloseacetaat membraanfilters.

Video: An Efficient Method for Selective Desalination of Radioactive Iodine Anions by Using Gold Nanoparticles-Embedded Membrane Filter

Synthesis and Purification of Iodoaziridines Involving Quantitative Selection of the Optimal Stationary Phase for Chromatography

The highly diastereoselective preparation of cis-N-Ts-iodoaziridines through reaction of diiodomethyllithium with N-Ts aldimines is described. Diiodomethyllithium is prepared by the deprotonation of diiodomethane with LiHMDS, in a THF/diethyl ether mixture, at -78 &#176;C in the dark. These conditions are essential for the stability of the LiCHI2 reagent generated. The subsequent dropwise addition of N-Ts aldimines to the preformed diiodomethyllithium solution affords an amino-diiodide intermediate, which is not isolated. Rapid warming of the reaction mixture to 0 &#176;C promotes cyclization to afford iodoaziridines with exclusive cis-diastereoselectivity. The addition and cyclization stages of the reaction are mediated in one reaction flask by careful temperature control.
Due to the sensitivity of the iodoaziridines to purification, assessment of suitable methods of purification is required. A protocol to assess the stability of sensitive compounds to stationary phases for column chromatography is described. This method is suitable to apply to new iodoaziridines, or other potentially sensitive novel compounds. Consequently this method may find application in range of synthetic projects. The procedure involves firstly the assessment of the reaction yield, prior to purification, by 1H NMR spectroscopy with comparison to an internal standard. Portions of impure product mixture are then exposed to slurries of various stationary phases appropriate for chromatography, in a solvent system suitable as the eluent in flash chromatography. After stirring for 30 min to mimic chromatography, followed by filtering, the samples are analyzed by 1H NMR spectroscopy. Calculated yields for each stationary phase are then compared to that initially obtained from the crude reaction mixture. The results obtained provide a quantitative assessment of the stability of the compound to the different stationary phases; hence the optimal can be selected. The choice of basic alumina, modified to activity IV, as a suitable stationary phase has allowed isolation of certain iodoaziridines in excellent yield and purity.

A protocol for the diastereoselective one-pot preparation of cis-N-Ts-iodoaziridines is described. The generation of diiodomethyllithium, addition to N-Ts aldimines and cyclization of the amino gem-diiodide intermediate to iodoaziridines is demonstrated. Also included is a protocol to rapidly and quantitatively assess the most appropriate stationary phase for purification by chromatography.

The highly diastereoselective preparation of cis-N-Ts-iodoaziridines through reaction of diiodomethyllithium with N-Ts aldimines is described. ...

Chemistry

On-chip Isotachophoresis for Separation of Ions and Purification of Nucleic Acids

Electrokinetic techniques are a staple of microscale applications because of their unique ability to perform a variety of fluidic and electrophoretic processes in simple, compact systems with no moving parts. Isotachophoresis (ITP) is a simple and very robust electrokinetic technique that can achieve million-fold preconcentration1,2 and efficient separation and extraction based on ionic mobility.3 For example, we have demonstrated the application of ITP to separation and sensitive detection of unlabeled ionic molecules (e.g. toxins, DNA, rRNA, miRNA) with little or no sample preparation4-8 and to extraction and purification of nucleic acids from complex matrices including cell culture, urine, and blood.9-12
ITP achieves focusing and separation using an applied electric field and two buffers within a fluidic channel system. For anionic analytes, the leading electrolyte (LE) buffer is chosen such that its anions have higher effective electrophoretic mobility than the anions of the trailing electrolyte (TE) buffer (Effective mobility describes the observable drift velocity of an ion and takes into account the ionization state of the ion, as described in detail by Persat et al.13). After establishing an interface between the TE and LE, an electric field is applied such that LE ions move away from the region occupied by TE ions. Sample ions of intermediate effective mobility race ahead of TE ions but cannot overtake LE ions, and so they focus at the LE-TE interface (hereafter called the "ITP interface"). Further, the TE and LE form regions of respectively low and high conductivity, which establish a steep electric field gradient at the ITP interface. This field gradient preconcentrates sample species as they focus. Proper choice of TE and LE results in focusing and purification of target species from other non-focused species and, eventually, separation and segregation of sample species.
We here review the physical principles underlying ITP and discuss two standard modes of operation: "peak" and "plateau" modes. In peak mode, relatively dilute sample ions focus together within overlapping narrow peaks at the ITP interface. In plateau mode, more abundant sample ions reach a steady-state concentration and segregate into adjoining plateau-like zones ordered by their effective mobility. Peak and plateau modes arise out of the same underlying physics, but represent distinct regimes differentiated by the initial analyte concentration and/or the amount of time allotted for sample accumulation.
We first describe in detail a model peak mode experiment and then demonstrate a peak mode assay for the extraction of nucleic acids from E. coli cell culture. We conclude by presenting a plateau mode assay, where we use a non-focusing tracer (NFT) species to visualize the separation and perform quantitation of amino acids.

Isotachophoresis (ITP) is a robust electrokinetic separation and preconcentration technique with applications ranging from toxin detection to sample preparation. We review the physical principles of ITP and the methodology of applying this technique to two specific example applications: separation and detection of small molecules and purification of nucleic acids from cell culture lysate.

Electrokinetic techniques are a staple of microscale applications because of their unique ability to perform a variety of fluidic and electrophoretic ...

Bioengineering

A Filter-based Surface Enhanced Raman Spectroscopic Assay for Rapid Detection of Chemical Contaminants

We demonstrate a method to fabricate highly sensitive surface-enhanced Raman spectroscopic (SERS) substrates using a filter syringe system that can be applied to the detection of various chemical contaminants. Silver nanoparticles (Ag NPs) are synthesized via reduction of silver nitrate by sodium citrate. Then the NPs are aggregated by sodium chloride to form nanoclusters that could be trapped in the pores of the filter membrane. A syringe is connected to the filter holder, with a filter membrane inside. By loading the nanoclusters into the syringe and passing through the membrane, the liquid goes through the membrane but not the nanoclusters, forming a SERS-active membrane. When testing the analyte, the liquid sample is loaded into the syringe and flowed through the Ag NPs coated membrane. The analyte binds and concentrates on the Ag NPs coated membrane. Then the membrane is detached from the filter holder, air dried and measured by a Raman instrument. Here we present the study of the volume effect of Ag NPs and sample on the detection sensitivity as well as the detection of 10 ppb ferbam and 1 ppm ampicillin using the developed assay.

A procedure for fabrication and performing the filter-based surface enhanced Raman spectroscopic (SERS) assay for the detection of chemical contaminants (i.e., pesticide ferbam and antibiotic ampicillin) is presented.

We demonstrate a method to fabricate highly sensitive surface-enhanced Raman spectroscopic (SERS) substrates using a filter syringe system that can be ...

Sulfate Separation by Selective Crystallization with a Bis-iminoguanidinium Ligand

A simple and effective method for selective sulfate separation from aqueous solutions by crystallization with a bis-guanidinium ligand, 1,4-benzene-bis(iminoguanidinium) (BBIG), is demonstrated. The ligand is synthesized as the chloride salt (BBIG-Cl) by in situ imine condensation of terephthalaldehyde with aminoguanidinium chloride in water, followed by crystallization as the sulfate salt (BBIG-SO4). Alternatively, BBIG-Cl is synthesized ex situ in larger scale from ethanol. The sulfate separation ability of the BBIG ligand is demonstrated by selective and quantitative crystallization of sulfate from seawater. The ligand can be recycled by neutralization of BBIG-SO4 with aqueous NaOH and crystallization of the neutral bis-iminoguanidine, which can be converted back into BBIG-Cl with aqueous HCl and reused in another separation cycle. Finally, 35S-labeled sulfate and &#946; liquid scintillation counting are employed for monitoring the sulfate concentration in solution. Overall, this protocol will instruct the user in the necessary skills to synthesize a ligand, employ it in the selective crystallization of sulfate from aqueous solutions, and quantify the separation efficiency.

A protocol for in situ aqueous synthesis of a bis(iminoguanidinium) ligand and its utilization in selective separation of sulfate is presented.

A simple and effective method for selective sulfate separation from aqueous solutions by crystallization with a bis-guanidinium ligand, ...

An Optimized Protocol for the Efficient Radiolabeling of Gold Nanoparticles by Using a 125I-labeled Azide Prosthetic Group

Here, we demonstrate a detailed protocol for the radiosynthesis of a 125I-labeled azide prosthetic group and its application to the efficient radiolabeling of DBCO-group-functionalized gold nanoparticles using a copper-free click reaction. Radioiodination of the stannylated precursor (2) was carried out by using [125I]NaI and chloramine T as an oxidant at room temperature for 15 min. After HPLC purification of the crude product, the purified 125I-labeled azide (1) was obtained with high radiochemical yield (75 &plusmn; 10%, n = 8) and excellent radiochemical purity (&gt;99%). For the synthesis of radiolabeled 13-nm-sized gold nanoparticles, the DBCO-functionalized gold nanoparticles (3) were prepared by using a thiolated polyethylene glycol polymer. A copper-free click reaction between 1 and 3 gave the 125I-labeled gold nanoparticles (4) with more than 95% of radiochemical yield as determined by radio-thin-layer chromatography (radio-TLC). These results clearly indicate that the present radiolabeling method using a strain-promoted copper-free click reaction will be useful for the efficient and convenient radiolabeling of DBCO-group-containing nanomaterials.

An Optimized Protocol for the Efficient Radiolabeling of Gold Nanoparticles by Using a 125I-labeled Azide Prosthetic Group

A detailed procedure for the synthesis of a 125I-labeled azide and the radiolabeling of dibenzocyclooctyne (DBCO)-group-conjugated, 13-nm-sized gold nanoparticles using a copper-free click reaction is described.

Here, we demonstrate a detailed protocol for the radiosynthesis of a 125I-labeled azide prosthetic group and its application to the efficient ...

Removal of Arsenic Using a Cationic Polymer Gel Impregnated with Iron Hydroxide

In this work, we prepared an adsorbent composed of a cationic polymer gel containing iron hydroxide in its structure designed to adsorb arsenic from groundwater. The gel we selected was the N,N-dimethylamino propylacrylamide methyl chloride quaternary (DMAPAAQ) gel. The objective of our preparation method was to ensure the maximum content of iron hydroxide in the structure of the gel. This design approach enabled simultaneous adsorption by both the polymer structure of the gel and the iron hydroxide component, thus, enhancing the adsorption capacity of the material. To examine the performance of the gel, we measured reaction kinetics, carried out pH sensitivity and selectivity analyses, monitored arsenic adsorption performance, and conducted regeneration experiments. We determined that the gel undergoes a chemisorption process and reaches equilibrium at 10 h. Moreover, the gel adsorbed arsenic effectively at neutral pH levels and selectively in complex ion environments, achieving a maximum adsorption volume of 1.63 mM/g. The gel could be regenerated with 87.6% efficiency and NaCl could be used for desorption instead of harmful NaOH. Taken together, the presented gel-based design method is an effective approach for constructing high-performance arsenic adsorbents.

In this work, we prepared an adsorbent composed of the cationic N,N-dimethylamino propylacrylamide methyl chloride quaternary (DMAPAAQ) polymer gel and iron hydroxide for adsorbing arsenic from groundwater. The gel was prepared via a novel method designed to ensure the maximum content of iron particles in its structure.

In this work, we prepared an adsorbent composed of a cationic polymer gel containing iron hydroxide in its structure designed to adsorb arsenic from ...

Environment

A Dual-Functional Electroactive Filter Towards Simultaneously Sb(III) Oxidation and Sequestration

We have designed a facile method to synthesize a dual-functional electrochemical filter consisting of two 1-D materials: titanate nanowires and carbon nanotubes. The hybrid titanate-CNT filter was prepared by a sonication coupled with a post-filtration route. Due to the synergistic effects of the increased number of exposed sorption sites, electrochemical reactivity, small pore size of the titanate-CNT network coupled with a flow-through design, simultaneous Sb(III) oxidation and sequestration can be readily achieved. Atomic fluorescence spectrometer technology demonstrated that the applied electrical field accelerates the Sb(III) conversion rate and the as-obtained Sb(V) were adsorbed effectively by the titanate nanowires due to their Sb specificity. This protocol provides a practical solution for the removal of highly toxic Sb(III) and other similar heavy metal ions.

A Dual-Functional Electroactive Filter Towards Simultaneously SbIII Oxidation and Sequestration

A protocol for the rational design of a dual-functional electroactive filter consisting of carbon nanotubes and titanate nanowires is reported and their environmental applications towards Sb(III) oxidation and sequestration is presented.

We have designed a facile method to synthesize a dual-functional electrochemical filter consisting of two 1-D materials: titanate nanowires and carbon ...

Production of High-Titer Recombinant Newcastle Disease Virus from Allantoic Fluid

Newcastle disease virus (NDV), also known as avian orthoavulavirus serotype-1, is a negative sense, single-stranded RNA virus that has been developed both as an oncolytic virus and a viral-vectored vaccine. NDV is an attractive therapeutic and prophylactic agent due to its well-established reverse genetics system, potent immunostimulatory properties, and excellent safety profile. When administered as an oncolytic virus or a viral-vectored vaccine, NDV elicits a robust antitumor or antigen-specific immune response, activating both the innate and adaptive arms of the immune system. 
Given these desirable characteristics, NDV has been evaluated in numerous clinical trials and is one of the most well-studied oncolytic viruses. Currently, there are two registered clinical trials involving NDV: one evaluating a recombinant NDV-vectored vaccine for SARS-CoV-2 (NCT04871737), and a second evaluating a recombinant NDV encoding Interleukin-12 in combination with Durvalumab, an antiPD-L1 antibody (NCT04613492). To facilitate further advancement of this highly promising viral vector, simplified methods for generating high-titer, in vivo-grade, recombinant NDV (rNDV) are needed. 
This paper describes a detailed procedure for amplifying rNDV in specified pathogen-free (SPF) embryonated chicken eggs and purifying rNDV from allantoic fluid, with improvements to reduce loss during purification. Also included are descriptions of the recommended quality control assays, which should be performed to confirm lack of contaminants and virus integrity. Overall, this detailed procedure enables the synthesis, purification, and storage of high-titer, in vivo-grade, recombinant, lentogenic, and mesogenic NDV for use in preclinical studies.

Here we provide a detailed procedure for production, purification, and quantification of high-titer recombinant Newcastle disease virus. This protocol consistently yields &#62; 6 &#215; 109 plaque-forming units/mL, providing virus quantities appropriate for in vivo animal studies. Additional quality control assays to ensure safety in vivo are described.

Newcastle disease virus (NDV), also known as avian orthoavulavirus serotype-1, is a negative sense, single-stranded RNA virus that has been developed both ...

Cancer Research

Nanosensors to Detect Protease Activity In Vivo for Noninvasive Diagnostics

Proteases are multi-functional enzymes that specialize in the hydrolysis of peptide-bonds and control broad biological processes including homeostasis and allostasis. Moreover, dysregulated protease activity drives pathogenesis and is a functional biomarker of diseases such as cancer; therefore, the ability to detect protease activity in vivo may provide clinically relevant information for biomedical diagnostics. The goal of this protocol is to create nanosensors that probe for protease activity in vivo by producing a quantifiable signal in urine. These protease nanosensors consist of two components: a nanoparticle and substrate. The nanoparticle functions to increase circulation half-life and substrate delivery to target disease sites. The substrate is a short peptide sequence (6-8 AA), which is designed to be specific to a target protease or group of proteases. The substrate is conjugated to the surface of the nanoparticle and is terminated by a reporter, such as a fluorescent marker, for detection. As dysregulated proteases cleave the peptide substrate, the reporter is filtered into urine for quantification as a biomarker of protease activity. Herein we describe construction of a nanosensor for matrix metalloproteinase 9 (MMP9), which is associated with tumor progression and metastasis, for detection of colorectal cancer in a mouse model.

Nanosensors to Detect Protease Activity In Vivo for Noninvasive Diagnostics

Proteases are tightly regulated enzymes involved in fundamental biological processes, and dysregulated protease activity drives progression of complex diseases such as cancer. This method&#39;s goal is to create nanosensors that measure protease activity in vivo by producing a cleavage signal that is detectable from host urine and discriminates disease.

Proteases are multi-functional enzymes that specialize in the hydrolysis of peptide-bonds and control broad biological processes including homeostasis and ...

Tangential Flow Ultrafiltration: A  &ldquo;Green&rdquo; Method for the Size Selection and Concentration of Colloidal Silver Nanoparticles

Nowadays, AgNPs are extensively used in the manufacture of consumer products,1 water disinfectants,2 therapeutics,1, 3 and biomedical devices4 due to their powerful antimicrobial properties.3-6 These nanoparticle applications are strongly influenced by the AgNP size and aggregation state. Many challenges exist in the controlled fabrication7 and size-based isolation4,8 of unfunctionalized, homogenous AgNPs that are free from chemically aggressive capping/stabilizing agents or organic solvents.7-13 Limitations emerge from the toxicity of reagents, high costs or reduced efficiency of the AgNP synthesis or isolation methods (e.g., centrifugation, size-dependent solubility, size-exclusion chromatography, etc.).10,14-18 To overcome this, we recently showed that TFU permits greater control over the size, concentration and aggregation state of Creighton AgNPs (300 ml of 15.3 &mu;g ml-1 down to 10 ml of 198.7 &mu;g ml-1) than conventional methods of isolation such as ultracentrifugation.19
TFU is a recirculation method commonly used for the weight-based isolation of proteins, viruses and cells.20,21 Briefly, the liquid sample is passed through a series of hollow fiber membranes with pore size ranging from 1,000 kD to 10 kD. Smaller suspended or dissolved constituents in the sample will pass through the porous barrier together with the solvent (filtrate), while the larger constituents are retained (retentate). TFU may be considered a "green" method as it neither damages the sample nor requires additional solvent to eliminate toxic excess reagents and byproducts. Furthermore, TFU may be applied to a large variety of nanoparticles as both hydrophobic and hydrophilic filters are available.
The two main objectives of this study were: 1) to illustrate the experimental aspects of the TFU approach through an invited video experience and 2) to demonstrate the feasibility of the TFU method for larger volumes of colloidal nanoparticles and smaller volumes of retentate. First, unfuctionalized AgNPs (4 L, 15.2 &mu;g ml-1) were synthesized using the well-established Creighton method22,23 by the reduction of AgNO3 with NaBH4. AgNP polydispersity was then minimized via a 3-step TFU using a 50-nm filter (460 cm2) to remove AgNPs and AgNP-aggregates larger than 50 nm, followed by two 100-kD (200 cm2 and 20 cm2) filters to concentrate the AgNPs. Representative samples were characterized using transmission electron microscopy, UV-Vis absorption spectrophotometry, Raman spectroscopy, and inductively coupled plasma optical emission spectroscopy. The final retentate consisted of highly concentrated (4 ml, 8,539.9 &mu;g ml-1) yet lowly aggregated and homogeneous AgNPs of 1-20 nm in diameter. This corresponds to a silver concentration yield of about 62%.

Tangential flow ultrafiltration (TFU) is a recirculation method used for the weight-based separation of biosamples. TFU was adapted to size-select (1-20 nm diameter) and highly concentrate a large volume of polydisperse silver nanoparticles (4 L of 15.2 &mu;g ml-1 down to 4 ml of 8,539.9 &mu;g ml-1) with minimal aggregation.

Nowadays, AgNPs are extensively used in the manufacture of consumer products,1 water disinfectants,2 therapeutics,1, 3 and biomedical devices4 due to ...

An Efficient Method for Selective Desalination of Radioactive Iodine Anions by Using Gold Nanoparticles-Embedded Membrane Filter

Samenvatting

Meer video's verkennen