この作品は、中国の国家自然科学基金 (51420105006, 51322501 番) によって支えられました。ダニエルは、高粘度のアイデアの彼の役に立つ議論を感謝いたします。

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著者が明らかに何もありません。

位相反転共同フロー デバイスは、単分散高粘度液滴を生成するシンプルでストレート forward メソッドを提供します。このデバイスは、基本的な共同流れ構造成っているうち出口出口管に接続されている中央の管に挿入されるインナー チューブ共同流れの共通のデバイスに同じような構造です。ただし、粘性η > 1 Pa·s の高粘度液滴生成の位相反転共同フロー デバイスと共通の共同フロ...

液滴の生成はドラッグデリバリー、材料合成、3 D バイオプリンティング、細胞アッセイ、食品工学1,2,3、4などのアプリケーションのさまざまな重要な技術になって,5,6t 字路7、8、マイクロ流体デバイス共同フロー1,9、または10,11構造の流れ中心の径を生成に使用される広く。片面乳剤のしぶき。粘性の連続相の選択滴12の形成を促進し、両方連続で分散した流体の粘度は一般的液滴マイクロ130.1 Pa 以下。ただし、多くのアプリケーションで分散相があります粘度いくつかグリセロール14などの水の百倍以上ナノ粒子15、タンパク質16、またはポリマー17を含む溶液,18,19、高粘度流体の安定した政権11マイクロ流体デバイス、特に粘性η > 1 Pa·s14 の流体を滴下から直接単分散液滴を達成するために困難ですが、17,18,19。さらに、それは報告された13,18典型的なマイクロ液滴形成法が比較的低粘度で安定した滴り均一液滴を形成する適度な界面張力の流体を必要とすることをされています。政権。
粘度 0.1 Pa よりわずかに大きい分散相、典型的な t 字路、共同のフロー、またはマイクロ流体デバイスのフロー中心のしぶきの形成を容易にするいくつかのアプローチがあります: (1) 減少分散の粘度揮発性溶剤11,20; の希釈による相(2) 連続相1,11; の粘度を高めることによって分散-に連続粘度比を減少させる(3) 高分散した連続流量率比14,19を維持しながら、非常に低い値に分散相の流量を減少させます。ただし、これらのアプローチは彼らは揮発性の溶剤や連続相の消費を劇的に上げながら生産率を下げる大幅にはるかに高い粘度を持つ液体のための実用的ではありません。加えて、 η > 1 Pa·s による高粘度高分子溶液のいくつかまだを破壊しないこと液滴に17,19上記アプローチが報告されています。
容易に高粘度液滴生成システムに流体の第 3 段階を紹介するマイクロ流体デバイスのいくつかの改良設計もあります。技術革新を含める: 液滴21dipsersed 相と連続相18日の中間段階として導入、適度な粘度と不混和引率流体にジェッティング スレッドをカットする導入された気泡と2 低粘度前駆体21,22,23から高粘度液滴を生成する導入されたマイクロリアクター。ただし、1 つのより多くの液体は、プロセスに関与している、システムがより複雑になる、デバイスの通常単一エマルジョン液滴の生成の典型的なデバイスよりもはるかに狭い流領域で動作します。
Η > 1 Pa·s、表面制御位相反転方式と高粘度流体から直接水滴がされている単分散を生成するには、24を調べた。低粘度液滴の生成は高粘度液滴12のそれよりはるかに簡単、高粘度の連続相の細長い低粘度液滴がまず典型的な共同フロー構造を使用して生成されます、ため分割下流共同流れ構造の表面濡れ性の変化。位相反転が完了するようにリリースされた低粘度流体には液滴に下流の高粘度流体逆にカプセル化します。位相反転機構によると単分散高粘度液滴は共同流量装置の出口を低粘度液で湿らせたことを扱いより広いチューブ24 に接続しながら典型的な共同フロー デバイスに基づいて生成することができます。 ,25。

<table>
	<tbody>
		<tr>
			<td>VitroTubes Glass Tubing</td>
			<td>VitroCom</td>
			<td>8240</td>
			<td>Square - Miniature Hollow Glass Tubing, I.D.=0.4mm, OD=0.8mm</td>
		</tr>
		<tr>
			<td>VitroTubes Glass Tubing</td>
			<td>VitroCom</td>
			<td>CV2033</td>
			<td>Round - Miniature Hollow Glass Tubing, I.D.=0.2mm, O.D.=0.33mm</td>
		</tr>
		<tr>
			<td>VitroTubes Glass Tubing</td>
			<td>VitroCom</td>
			<td>CV1017</td>
			<td>Round - Miniature Hollow Glass Tubing, I.D.=0.1mm, O.D.=0.17mm</td>
		</tr>
		<tr>
			<td>VitroTubes Glass Tubing</td>
			<td>VitroCom</td>
			<td>Q14606</td>
			<td>Square - Miniature Hollow Glass Tubing, I.D.=1.05mm+0.1/-0, OD=1.5mm</td>
		</tr>
		<tr>
			<td>Standard Glass Capillaries</td>
			<td>WPI</td>
			<td>1B100-6</td>
			<td>Round - Glass Tubing, I.D.=0.58mm, O.D.=1.00mm</td>
		</tr>
		<tr>
			<td>Glycerol</td>
			<td>Sinopharm Chemical Reagent Beijing</td>
			<td>10010618</td>
			<td></td>
		</tr>
		<tr>
			<td>Paraffin Liquid</td>
			<td>Sinopharm Chemical Reagent Beijing</td>
			<td>30139828</td>
			<td></td>
		</tr>
		<tr>
			<td>Poly(vinyl alcohol), PVA-124</td>
			<td>Sinopharm Chemical Reagent Beijing</td>
			<td>30153084</td>
			<td></td>
		</tr>
		<tr>
			<td>Span 80</td>
			<td>Sigma-Aldrich</td>
			<td>85548</td>
			<td></td>
		</tr>
		<tr>
			<td>Starch</td>
			<td>Sigma-Aldrich</td>
			<td>S9765</td>
			<td></td>
		</tr>
		<tr>
			<td>Trichloro(octadecyl)silane</td>
			<td>Sigma-Aldrich</td>
			<td>104817</td>
			<td></td>
		</tr>
		<tr>
			<td>Toluidine Blue O</td>
			<td>Sigma-Aldrich</td>
			<td>T3260</td>
			<td></td>
		</tr>
		<tr>
			<td>Honey</td>
			<td></td>
			<td></td>
			<td>Chaste tree honey, common food product purchased from supermarket</td>
		</tr>
		<tr>
			<td>DEVCON 5 Minute Epoxy</td>
			<td>ITW&#160;</td>
			<td></td>
			<td>Epoxy glue</td>
		</tr>
		<tr>
			<td>Blunt Tip Stainless Steel Dispensing Needles (Luer Lock)</td>
			<td>Suzhou Lanbo Needle, China</td>
			<td>LTA820050</td>
			<td>20G x 1/2&#34;&#160;</td>
		</tr>
		<tr>
			<td>Tungsten/Carbide Scriber</td>
			<td>Ullman</td>
			<td>1830</td>
			<td>For cutting glass tubing</td>
		</tr>
		<tr>
			<td>Microscope Slides</td>
			<td>Sail Brand</td>
			<td>7101</td>
			<td>76.2 mm x 25.4 mm, Thickness 1 - 1.2 mm</td>
		</tr>
		<tr>
			<td>Polyethylene Tubing</td>
			<td>Scientific Commodities</td>
			<td>BB31695-PE/5</td>
			<td>I.D. = 0.86 mm, O.D. = 1.32 mm</td>
		</tr>
		<tr>
			<td>Syringe Pumps</td>
			<td>Longer Pump, China</td>
			<td>LSP01-1A</td>
			<td>3 pumps needed for the experiments</td>
		</tr>
	</tbody>
</table>

fabricating high-viscosity droplets using microfluidic capillary device with phase-inversion co-flow structure

粘度の高い単分散液滴の生成液滴マイクロ流路中の挑戦をされている常に。ここでは、粘度の低い流体で均一の高粘度液滴を生成する位相反転共同フロー デバイスを示します。マイクロ流体キャピラリー デバイスより広いチューブに接続する出口と共通の共同フロー構造を持っています。低粘度流体の細長い水滴最初共同流れ構造の高粘度流体によってカプセル化されます。位相反転は後続の逆の結果、出口の先端に低粘度液滴付着によるを誘導し, 細長い低粘度液滴粘度の低い流体で接液するのに扱われます、出口を通過高粘度流体のカプセル化。結果高粘度液滴の大きさは、高粘度流体の低粘度流体の流れ率比を変更することによって調整できます。グリセリンや蜂蜜、澱粉、高分子溶液などの 11.9 Pas まで粘度高粘度液滴の生成のいくつかの典型的な例を示します。メソッドは、さまざまな材料の合成、ドラッグデリバリー、細胞アッセイ、バイオ エンジニア リング、食品などの液滴ベースのアプリケーションで使用されるかもしれない単分散高粘度液滴を生成するシンプルで簡単なアプローチを提供します。エンジニア リング。

図 1 aに示すように、位相反転、共同の流れ構造とマイクロ流体キャピラリー デバイスが単分散水溶液の高粘度液滴を生成する設計されました。図 1、高粘度の水性相はηwの粘度、グリセリン = 1.4 Pa低粘度油相はηoの粘度のある液体パラフィン 0.029 Pa を =2 つの段階間の表面張力は γ = 27.7 mN/m。...

Watch this Scientific Journal Video about Fabricating High-viscosity Droplets using Microfluidic Capillary Device with Phase-inversion Co-flow Structure at JoVE.com

Fabricating High-viscosity Droplets using Microfluidic Capillary Device with Phase-inversion Co-flow Structure

位相反転共同フロー構造を有するマイクロ流体デバイスをキャピラリーを用いた加工の高粘度液滴

1 Pa は、液滴マイクロ流体システムで実現することは困難である上径高粘度液滴を生成する位相反転共同フロー デバイスを示します。

The generation of monodisperse droplets with high viscosity has always been a challenge in droplet microfluidics. Here, we demonstrate a phase-inversion ...

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10.2K ビュー.  University of Science and Technology Beijing. 1 Pa は、液滴マイクロ流体システムで実現することは困難である上径高粘度液滴を生成する位相反転共同フロー デバイスを示します。

ビデオ: Fabricating High-viscosity Droplets using Microfluidic Capillary Device with Phase-inversion Co-flow Structure

Fabricating Nanogaps by Nanoskiving

There are several methods of fabricating nanogaps with controlled spacings, but the precise control over the sub-nanometer spacing between two electrodes-and generating them in practical quantities-is still challenging. The preparation of nanogap electrodes using nanoskiving, which is a form of edge lithography, is a fast, simple and powerful technique. This method is an entirely mechanical process which does not include any photo- or electron-beam lithographic steps and does not require any special equipment or infrastructure such as clean rooms. Nanoskiving is used to fabricate electrically addressable nanogaps with control over all three dimensions; the smallest dimension of these structures is defined by the thickness of the sacrificial layer (Al or Ag) or self-assembled monolayers. These wires can be manually positioned by transporting them on drops of water and are directly electrically-addressable; no further lithography is required to connect them to an electrometer.

The fabrication of electrically addressable, high-aspect-ratio (> 1000:1) metal nanowires separated by gaps of single nanometers using either sacrificial layers of aluminum and silver or self-assembled monolayers as templates is described. These nanogap structures are fabricated without a clean room or any photo- or electron-beam lithographic processes by a form of edge lithography known as nanoskiving.

Nanoskivingによるナノギャップを作製

There are several methods of fabricating nanogaps with controlled spacings, but the precise control over the sub-nanometer spacing between two ...

化学

Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR

Copper (I) binding by metallochaperone transport proteins prevents copper oxidation and release of the toxic ions that may participate in harmful redox reactions. The Cu (I) complex of the peptide model of a Cu (I) binding metallochaperone protein, which includes the sequence MTCSGCSRPG (underlined is conserved), was determined in solution under inert conditions by NMR spectroscopy.
NMR is a widely accepted technique for the determination of solution structures of proteins and peptides. Due to difficulty in crystallization to provide single crystals suitable for X-ray crystallography, the NMR technique is extremely valuable, especially as it provides information on the solution state rather than the solid state. Herein we describe all steps that are required for full three-dimensional structure determinations by NMR. The protocol includes sample preparation in an NMR tube, 1D and 2D data collection and processing, peak assignment and integration, molecular mechanics calculations, and structure analysis. Importantly, the analysis was first conducted without any preset metal-ligand bonds, to assure a reliable structure determination in an unbiased manner.

Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR

The NMR-solution structure of a metallochaperone model peptide with Cu (I) was determined, and a detailed protocol from sample preparation and 1D and 2D data collection to a three-dimensional structure is described.

Copper (I) binding by metallochaperone transport proteins prevents copper oxidation and release of the toxic ions that may participate in harmful redox ...

Capillary Electrophoresis to Monitor Peptide Grafting onto Chitosan Films in Real Time

Free-solution capillary electrophoresis (CE) separates analytes, generally charged compounds in solution through the application of an electric field. Compared to other analytical separation techniques, such as chromatography, CE is cheap, robust and effectively requires no sample preparation (for a number of complex natural matrices or polymeric samples). CE is fast and can be used to follow the evolution of mixtures in real time (e.g., chemical reaction kinetics), as the signals observed for the separated compounds are directly proportional to their quantity in solution.
Here, the efficiency of CE is demonstrated for monitoring the covalent grafting of peptides onto chitosan films for subsequent biomedical applications. Chitosan&#39;s antimicrobial and biocompatible properties make it an attractive material for biomedical applications such as cell growth substrates. Covalently grafting the peptide RGDS (arginine - glycine - aspartic acid - serine) onto the surface of chitosan films aims at improving cell attachment. Historically, chromatography and amino acid analysis have been used to provide a direct measurement of the amount of grafted peptide. However, the fast separation and absence of sample preparation provided by CE enables equally accurate yet real-time monitoring of the peptide grafting process. CE is able to separate and quantify the different components of the reaction mixture: the (non-grafted) peptide and the chemical coupling agents. In this way the use of CE results in improved films for downstream applications.
The chitosan films were characterized through solid-state NMR (nuclear magnetic resonance) spectroscopy. This technique is more time-consuming and cannot be applied in real time, but yields a direct measurement of the peptide and thus validates the CE technique.

Free solution capillary electrophoresis is a fast, cheap and robust analytical method that enables the quantitative monitoring of chemical reactions in real time. Its utility for rapid, convenient and precise analysis is demonstrated here through analysis of covalent peptide grafting onto chitosan films for improved cell adhesion.

リアルタイムでのキトサンフィルム上にペプチドグラフトを監視するためのキャピラリー電気泳動

Free-solution capillary electrophoresis (CE) separates analytes, generally charged compounds in solution through the application of an electric field. ...

Using Capillary Electrophoresis to Quantify Organic Acids from Plant Tissue: A Test Case Examining Coffea arabica Seeds

Carboxylic acids are organic acids containing one or more terminal carboxyl (COOH) functional groups. Short chain carboxylic acids (SCCAs; carboxylic acids containing three to six carbons), such as malate and citrate, are critical to the proper functioning of many biological systems, where they function in cellular respiration and can serve as indicators of cell health. In foods, organic acid content can have significant impact on taste, with increased SCCA levels resulting in a sour or &#34;acid&#34; taste. Because of this, methods for the rapid analysis of organic acid levels are of particular interest to the food and beverage industries. Unfortunately, however, most methods used for SCCA quantification are dependent on time-consuming protocols requiring the derivatization of samples with hazardous reagents, followed by costly chromatographic and/or mass spectrometric analyses. This method details an alternate method for the detection and quantification of organic acids from plant material and food samples using free zonal capillary electrophoresis (CZE), sometimes simply referred to as capillary electrophoresis (CE). CZE provides a cost-effective method for measuring SCCAs with a low limit of detection (0.005 mg/ml). This article details the extraction and quantification of SCCAs from plant samples. While the method provided focuses on measurement of SCCAs from coffee beans, the method provided can be applied to multiple plant-based food materials.

Using Capillary Electrophoresis to Quantify Organic Acids from Plant Tissue: A Test Case Examining Coffea arabica Seeds

This article presents a method for the detection and quantification of organic acids from plant material using free zonal capillary electrophoresis. An example of the potential application of this method, determining the effects of a secondary fermentation on organic acid levels in coffee seeds, is provided.

植物組織からの有機酸を定量化するためにキャピラリー電気泳動を使用した：テストケースを調べます<em&gt;コーヒーノキアラビカ</em&gt;種子

Carboxylic acids are organic acids containing one or more terminal carboxyl (COOH) functional groups. Short chain carboxylic acids (SCCAs; carboxylic ...

Monitoring the Effects of Illumination on the Structure of Conjugated Polymer Gels Using Neutron Scattering

We demonstrate a protocol to effectively monitor the gelation process of a high concentration solution of conjugated polymer both in the presence and absence of white light exposure. By instituting a controlled temperature ramp, the gelation of these materials can be precisely monitored as they proceed through this structural evolution, which effectively mirrors the conditions experienced during the solution deposition phase of organic electronic device fabrication. Using small angle neutron scattering (SANS) and ultra-small angle neutron scattering (USANS) along with appropriate fitting protocols we quantify the evolution of select structural parameters throughout this process. Thorough analysis indicates that continued light exposure throughout the gelation process significantly alters the structure of the ultimately formed gel. Specifically, the aggregation process of poly(3-hexylthiophene-2,5-diyl) (P3HT) nano-scale aggregates is negatively affected by the presence of illumination, ultimately resulting in the retardation of growth in conjugated polymer microstructures and the formation of smaller scale macro-aggregate clusters.

A protocol for the analysis of gels formed from the optoelectronic conjugated polymer poly(3-hexylthiophene-2,5-diyl) (P3HT) using small and ultra-small angle neutron scattering in both the presence and absence of illumination is presented.

中性子散乱法を用いた共役高分子ゲルの構造に対する光照射効果のモニタリング

We demonstrate a protocol to effectively monitor the gelation process of a high concentration solution of conjugated polymer both in the presence and ...

Preparation of Hollow Polystyrene Particles and Microcapsules by Radical Polymerization of Janus Droplets Consisting of Hydrocarbon and Fluorocarbon Oils

In this article, we have demonstrated a method for producing hollow particles and microcapsules using oil droplets consisting of hydrocarbon oil (styrene) and fluorocarbon oil (perfluoro-n-octane, PFO) in aqueous surfactant (sodium dodecylsulfate, SDS) solutions. Since fluorocarbon oils are immiscible with hydrocarbon oils, the two oils are separated. Emulsions are prepared by stirring styrene/PFO/aqueous SDS solution mixtures at 80 &#176;C. The type of emulsions and the morphology of droplets in the emulsions are observed by light microscope and scanning confocal fluorescence microscope. It is found that oil droplets with Janus-type morphologies consisting of mutually immiscible styrene and PFO are formed in aqueous SDS solutions. Polystyrene particles are fabricated by radical polymerization of the ternary mixtures of styrene/PFO/aqueous SDS solution at 80 &#176;C. The morphologies of the polystyrene are confirmed by scanning electron microscopy and scanning transmission electron microscopy observations. These observations show the preparation of hollow polystyrene particles with a single hole on the surface. To our knowledge, this method is a novel strategy using the immiscibility of hydrocarbon and fluorocarbon oils. The hollow particles can also be applied to the preparation of microcapsules.

A protocol for the fabrication of hollow polymer particles and microcapsules by radical polymerization using emulsions consisting of styrene, perfluoro-n-octane, and aqueous SDS (sodium dodecylsulfate) solution is presented.

中空のポリスチレン粒子と炭化水素とフッ素オイルから成るヤヌス液滴のラジカル重合によるマイクロ カプセルの調製

In this article, we have demonstrated a method for producing hollow particles and microcapsules using oil droplets consisting of hydrocarbon oil (styrene) ...

Probing the Structure and Dynamics of Interfacial Water with Scanning Tunneling Microscopy and Spectroscopy

Water/solid interfaces are ubiquitous and play a key role in many environmental, biophysical, and technological processes. Resolving the internal structure and probing the hydrogen-bond (H-bond) dynamics of the water molecules adsorbed on solid surfaces are fundamental issues of water science, which remains a great challenge owing to the light mass and small size of hydrogen. Scanning tunneling microscopy (STM) is a promising tool for attacking these problems, thanks to its capabilities of sub-&#197;ngstr&#246;m spatial resolution, single-bond vibrational sensitivity, and atomic/molecular manipulation. The designed experimental system consists of a Cl-terminated tip and a sample fabricated by dosing water molecules in situ onto the Au(111)-supported NaCl(001) surfaces. The insulating NaCl films electronically decouple the water from the metal substrates, so the intrinsic frontier orbitals of water molecules are preserved. The Cl-tip facilitates the manipulation of the single water molecules, as well as gating the orbitals of water to the proximity of Fermi level (EF) via tip-water coupling. This paper outlines the detailed methods of submolecular resolution imaging, molecular/atomic manipulation, and single-bond vibrational spectroscopy of interfacial water. These studies open up a new route for investigating the H-bonded systems at the atomic scale.

Here, we present a protocol to investigate the structure and dynamics of interfacial water at the atomic scale, in terms of submolecular resolution imaging, molecular manipulation, and single-bond vibrational spectroscopy.

構造と走査型トンネル顕微鏡および分光法による界面の水のダイナミクスを調べる

Water/solid interfaces are ubiquitous and play a key role in many environmental, biophysical, and technological processes. Resolving the internal ...

Synthesis and Structure Determination of &#181;-Conotoxin PIIIA Isomers with Different Disulfide Connectivities

Peptides with a high number of cysteines are usually influenced regarding the three-dimensional structure by their disulfide connectivity. It is thus highly important to avoid undesired disulfide bond formation during peptide synthesis, because it may result in a completely different peptide structure, and consequently altered bioactivity. However, the correct formation of multiple disulfide bonds in a peptide is difficult to obtain by using standard self-folding methods such as conventional buffer oxidation protocols, because several disulfide connectivities can be formed. This protocol represents an advanced strategy required for the targeted synthesis of multiple disulfide-bridged peptides which cannot be synthesized via buffer oxidation in high quality and quantity. The study demonstrates the application of a distinct protecting group strategy for the synthesis of all possible 3-disulfide-bonded peptide isomers of &#181;-conotoxin PIIIA in a targeted way. The peptides are prepared by Fmoc-based solid phase peptide synthesis using a protecting group strategy for defined disulfide bond formation. The respective pairs of cysteines are protected with trityl (Trt), acetamidomethyl (Acm), and tert-butyl (tBu) protecting groups to make sure that during every oxidation step only the required cysteines are deprotected and linked. In addition to the targeted synthesis, a combination of several analytical methods is used to clarify the correct folding and generation of the desired peptide structures. The comparison of the different 3-disulfide-bonded isomers indicates the importance of accurate determination and knowledge of the disulfide connectivity for the calculation of the three-dimensional structure and for interpretation of the biological activity of the peptide isomers. The analytical characterization includes the exact disulfide bond elucidation via tandem mass spectrometry (MS/MS) analysis which is performed with partially reduced and alkylated derivatives of the intact peptide isomer produced by an adapted protocol. Furthermore, the peptide structures are determined using 2D nuclear magnetic resonance (NMR) experiments and the knowledge obtained from MS/MS analysis.

Cysteine-rich peptides fold into distinct three-dimensional structures depending on their disulfide connectivity. Targeted synthesis of individual disulfide isomers is required when buffer oxidation does not lead to the desired disulfide connectivity. The protocol deals with the selective synthesis of 3-disulfide-bonded peptides and their structural analysis using NMR and MS/MS studies.

合成と異なる二硫化接続と μ-コノトキシン PIIIA 異性体の構造決定

Peptides with a high number of cysteines are usually influenced regarding the three-dimensional structure by their disulfide connectivity. It is thus ...

Large-scale Top-down Proteomics Using Capillary Zone Electrophoresis Tandem Mass Spectrometry

Capillary zone electrophoresis-electrospray ionization-tandem mass spectrometry (CZE-ESI-MS/MS) has been recognized as a useful tool for top-down proteomics that aims to characterize proteoforms in complex proteomes. However, the application of CZE-MS/MS for large-scale top-down proteomics has been impeded by the low sample-loading capacity and narrow separation window of CZE. Here, a protocol is described using CZE-MS/MS with a microliter-scale sample-loading volume and a 90-min separation window for large-scale top-down proteomics. The CZE-MS/MS platform is based on a linear polyacrylamide (LPA)-coated separation capillary with extremely low electroosmotic flow, a dynamic pH-junction-based online sample concentration method with a high efficiency for protein stacking, an electro-kinetically pumped sheath flow CE-MS interface with extremely high sensitivity, and an ion trap mass spectrometer with high mass resolution and scan speed. The platform can be used for the high-resolution characterization of simple intact protein samples and the large-scale characterization of proteoforms in various complex proteomes. As an example, a highly efficient separation of a standard protein mixture and a highly sensitive detection of many impurities using the platform is demonstrated. As another example, this platform can produce over 500 proteoform and 190 protein identifications from an Escherichia coli proteome in a single CZE-MS/MS run.

A detailed protocol is described for the separation, identification, and characterization of proteoforms in protein samples using capillary zone electrophoresis-electrospray ionization-tandem mass spectrometry (CZE-ESI-MS/MS). The protocol can be used for the high-resolution characterization of proteoforms in simple protein samples and the large-scale identification of proteoforms in complex proteome samples.

キャピラリー ゾーン電気泳動タンデム質量分析法による大規模なトップダウン プロテオミクス

Capillary zone electrophoresis-electrospray ionization-tandem mass spectrometry (CZE-ESI-MS/MS) has been recognized as a useful tool for top-down ...

High-throughput and Comprehensive Drug Surveillance Using Multisegment Injection-Capillary Electrophoresis-Mass Spectrometry

New analytical methods are urgently needed to enable high-throughput, yet comprehensive drug screening, given an alarming opioid and prescription drug crisis in public health. Conventional urine drug testing based on a two-tier immunoassay screen followed by a gas chromatography-tandem mass spectrometry (GC-MS/MS) or liquid chromatography-tandem mass spectrometry (LC-MS/MS) method are expensive and prone to bias while being limited to targeted panels of known drugs of abuse (DoA). Herein, we outline an improved method for drug surveillance that allows for the resolution and detection of an expanded panel of DoA and their metabolites when using multisegment injection-capillary electrophoresis-mass spectrometry (MSI-CE-MS). Multiplexed separations of ten urine samples with a quality control by CE (&lt; 3 min/sample) in conjunction with full-scan data acquisition using a time-of-flight mass spectrometer (TOF-MS) under positive ion mode detection allows for the identification and quantification of DoA above recommended cut-off levels. An excellent resolution of drug isomers and isobars, including background interferences, are achieved when using MSI-CE-MS with an electrokinetic spacer between sample segments, where accurate mass/molecular formula together with the comigration of a matching deuterated internal standard and the detection of one or more bio-transformed metabolites facilitate DoA identification over a wider detection window. Additionally, urine samples can be analyzed directly without enzyme deconjugation for the rapid screening without complicated sample workup. MSI-CE-MS enables the surveillance of a broad spectrum of DoA that is required for the treatment monitoring of high-risk patients, including confirming prescribed drug adherence, revealing illicit drug use/substitution, and evaluating optimal dosage regimes as required for new advances in precision medicine.

Here we describe a high-throughput method for comprehensive drug surveillance that allows for the improved resolution and detection of large panels of drugs of abuse and their metabolites, with quality control based on multisegment injection-capillary electrophoresis-mass spectrometry.

マルチ セグメントの注入キャピラリー電気泳動質量分析法による高スループットかつ包括的な薬物監視

New analytical methods are urgently needed to enable high-throughput, yet comprehensive drug screening, given an alarming opioid and prescription drug ...