作者希望通过澳大利亚政府的研究培训计划获得对摩根利的支持。

1. 颜色测试试剂溶液的制备
注: 将0.12 克硝酸铜重三水成干100毫升的烧杯。加入30毫升的去离子 (DI) 水, 在室温下小心地旋转, 以溶解所有固体。将这个溶液倒入100毫升的容积烧瓶中, 用 DI 水填充到标定的标记上。这个准备好的溶液是试剂1。 注: 试剂1可使用其他铜 (ii) 盐,如氯化铜 (ii) 制备。
<ol><li>称0.11 克 29-二甲基-110-邻菲咯啉 (试剂) 半水合物为干100毫升烧杯。加入50毫升0.10 摩尔/L 盐酸 (HCl), 并使用玻璃搅拌棒促进固体在室温下溶解。将这个溶液倒入100毫升的容积烧瓶中, 用0.10 摩尔/L HCl 填充到标定的标记上。这个准备好的溶液是试剂2。 注意: 试剂是剧毒的, 会引起皮肤发炎和严重的眼部损伤。在处理时戴上手套和安全眼镜, 以尽量减少暴露的风险。 注: 试剂只是微溶于水, 因此, 稀酸用于制备此试剂, 并确保所有固体溶解。</li>
	<li>将16.4 克醋酸钠放入干100毫升的烧杯中。加入50毫升的 DI 水, 用玻璃搅拌棒在室温下促进固体的溶解。将这个溶液倒入100毫升的容积烧瓶中, 用 DI 水填充到标定的标记上。这个准备好的溶液是试剂3。 注意: 协议可以在此处暂停。该试剂是高度稳定的, 可储存在室温下长达12月。</li>
</ol>2. 颜色测试
<ol><li>收集一个清洁的瓷斑板, 三一次性管, 三试剂解决方案在步骤 2.1, 一清洁刮刀, 电动板和样品/缴获的材料进行测试。</li>
	<li>使用刮刀, 放置一个小的, 针头大小的数量 (约 0.1-0.2 毫克) 的未知样品成三单独的井瓷斑板。留下三相邻井空 (空白控制) 和另外三个井与相等的数额 4-methylmethcathinone HCl (4-MMC), 一个综合 cathinone 参考样品 (正面控制)。 注: 首选的测试表面是瓷斑板。如果这些不可用, 使用塑料微板或半微型试管。</li>
	<li>使用一次性吸管, 添加5滴硝酸铜溶液 (试剂 1) 到每个样品井, 除了空白和积极控制井。</li>
	<li>使用第二个一次性吸管, 添加2滴的试剂溶液 (试剂 2) 到每个样品井, 除了空白和积极控制井。</li>
	<li>使用第三个一次性吸管, 添加2滴醋酸钠溶液 (试剂 3) 到每个样品井, 除了空白和积极控制井。 注: 溶液变成浅蓝色。</li>
	<li>将瓷斑板直接放置在80° c 的电动板上。 注: 请勿在板上直接加热塑料微板。准备一个浅沸腾的水浴, 设置塑料板。在小型沸水浴中加热半微量试管。观察颜色变化所需的精确时间将取决于光斑板的厚度和组成。 注意: 在处理斑点板时要小心, 以防烫伤。</li>
	<li>加热10分钟后, 用肉眼观察并注意最终颜色的变化或拍摄最后颜色变化的照片。 注意: 使用白色背景可以更好地可视化颜色变化。</li>
</ol>

<ol>
	<li>Martin, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Drugs on the Dark Net: How Cryptomarkets are Transforming the Global Trade in Illicit Drugs. , (2014).</li><li>Beharry, S., Gibbons, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+overview+of+emerging+and+new+psychoactive+substances+in.">An overview of emerging and new psychoactive substances in.</a> the United Kingdom. Forensic Sci. Int. 267, 25-34 (2016).</li><li>United Nations Office on Drugs and Crime (UNODC). <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> World Drug Report 2017. , (2017).</li><li>Australian Criminal Intelligence Commission (ACIC). <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Illicit Drug Data Report 2014-2015. , (2016).</li><li>United Nations Office on Drugs and Crime (UNODC). <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> World Drug Report 2016. , (2016).</li><li>Chatwin, C., Measham, F., O'Brien, K., Sumnall, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+drugs,+new+directions?+Research+priorities+for+new+psychoactive+substances+and+human+enhancement+drugs.">New drugs, new directions? Research priorities for new psychoactive substances and human enhancement drugs.</a> Int. J. Drug Policy. 40, 1-5 (2017).</li><li>Reuter, P., Pardo, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+psychoactive+substances:+Are+there+any+good+options+for+regulating+new+psychoactive+substances?.">New psychoactive substances: Are there any good options for regulating new psychoactive substances?.</a> Int. J. Drug Policy. 40, 117-122 (2017).</li><li>Elie, M. P., Elie, L. E., Baron, M. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Keeping+pace+with+NPS+releases:+fast+GC-MS+screening+of+legal+high+products.">Keeping pace with NPS releases: fast GC-MS screening of legal high products.</a> Drug Test. Anal. 5 (5), 281-290 (2013).</li><li>Strano Rossi, 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=An+analytical+approach+to+the+forensic+identification+of+different+classes+of+new+psychoactive+substances+(NPSs)+in+seized+materials.">An analytical approach to the forensic identification of different classes of new psychoactive substances (NPSs) in seized materials.</a> Rapid Commun Mass Sp. 28 (17), 1904-1916 (2014).</li><li>Jones, L. E., 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=Infrared+and+Raman+screening+of+seized+novel+psychoactive+substances:+a+large+scale+study+of+&gt;200+samples.">Infrared and Raman screening of seized novel psychoactive substances: a large scale study of &gt;200 samples.</a> Analyst. 141 (3), 902-909 (2016).</li><li>Lesiak, A. 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=Direct+analysis+in+real+time+mass+spectrometry+(DART-MS)+of+&amp;#34;bath+salt&amp;#34;+cathinone+drug+mixtures.">Direct analysis in real time mass spectrometry (DART-MS) of &amp;#34;bath salt&amp;#34; cathinone drug mixtures.</a> Analyst. 138 (12), 3424-3432 (2013).</li><li>Brown, H., Oktem, B., Windom, A., Doroshenko, V., Evans-Nguyen, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+Analysis+in+Real+Time+(DART)+and+a+portable+mass+spectrometer+for+rapid+identification+of+common+and+designer+drugs+on-site.">Direct Analysis in Real Time (DART) and a portable mass spectrometer for rapid identification of common and designer drugs on-site.</a> Forensic Chem. (Supplement C), 66-73 (2016).</li><li>Bruno, A. M., Cleary, S. R., O'Leary, A. E., Gizzi, M. C., Mulligan, C. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Balancing+the+utility+and+legality+of+implementing+portable+mass+spectrometers+coupled+with+ambient+ionization+in+routine+law+enforcement+activities.">Balancing the utility and legality of implementing portable mass spectrometers coupled with ambient ionization in routine law enforcement activities.</a> Anal Methods-UK. 9 (34), 5015-5022 (2017).</li><li>United Nations Office on Drugs and Crime (UNODC). <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Recommended methods for the identification and analysis of amphetamine, methamphetamine and their ring-substituted analogues in seized materials. , (2006).</li><li>Scientific Working Group for the Analysis of Seized Drugs (SWGDRUG). <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Vol. 7.1. , (2016).</li><li>United Nations Office on Drugs and Crime (UNODC). <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Recommended methods for the identification and analysis of synthetic cathinones in seized materials. , (2015).</li><li>Philp, M., Shimmon, R., Tahtouh, M., Fu, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+and+validation+of+a+presumptive+color+spot+test+method+for+the+detection+of+synthetic+cathinones+in+seized+illicit+materials.">Development and validation of a presumptive color spot test method for the detection of synthetic cathinones in seized illicit materials.</a> Forensic Chem. 1, 39-50 (2016).</li><li>Al-Obaid, A. M., Al-Tamrah, S. A., Aly, F. A., Alwarthan, A. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+(S)(&#8722;)-cathinone+by+spectrophotometric+detection.">Determination of (S)(&#8722;)-cathinone by spectrophotometric detection.</a> J Pharmaceut Biomed. 17 (2), 321-326 (1998).</li><li>Namera, A., Kawamura, M., Nakamoto, A., Saito, T., Nagao, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comprehensive+review+of+the+detection+methods+for+synthetic+cannabinoids+and+cathinones.">Comprehensive review of the detection methods for synthetic cannabinoids and cathinones.</a> Forensic Toxicol. 33 (2), 175-194 (2015).</li><li>Isaacs, R. C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+structure-reactivity+relationship+driven+approach+to+the+identification+of+a+color+test+protocol+for+the+presumptive+indication+of+synthetic+cannabimimetic+drugs+of+abuse.">A structure-reactivity relationship driven approach to the identification of a color test protocol for the presumptive indication of synthetic cannabimimetic drugs of abuse.</a> Forensic Sci. Int. 242, 135-141 (2014).</li></ol>

作者没有什么可透露的。

这种颜色测试协议是根据苏拉亚·奥贝德et al发布的实验工作改编的。18中, 作者演示了在阿拉伯茶叶工厂提取的 cathinone 中出现颜色变化的情况。对已公布的议定书进行修改是必要的, 以预见其在推定的非法药物检测中的应用。最重要的考虑是减少反应的规模。本文件所述的议定书旨在适用于街头抽样和药物缉获。
所描述的协议提供了一个简单的假设指示的存在的合成 cathinones 在一个样本。至关重要的是, 该协议的加热步骤是必要的, 以可视化的颜色变化的要求强度在规定的时间限制。瓷斑板的厚度和组成可能会影响由于板材材料的导热性而导致颜色变化所需的时间。10分钟的加热周期是为了允许这些差异。斑块也应该平放在板上, 这样所有的水井都能感受到同样的热量。加热现场板超过10分钟或在80° c 以上的温度可以通过水溶液的蒸发消极地影响结果。第二个关键步骤是添加所有三种试剂, 因为该协议将无法在没有全部三的情况下工作。
假定颜色测试被设计为对某一药物类有选择性;提供快速的结果, 并具有一定的可移植性, 允许在现场应用。热源的要求大大降低了测试方法的可移植性。此外, 10 分钟的加热周期不是等待假定颜色测试的理想时间长度, 而是此测试协议的限制。
该协议中发生的颜色变化的基础是一个非特定的还原-氧化反应, 这意味着合成 cathinone 分子不是一个配体在最后的有色复杂。这种固有的非特定反应意味着有可能会干扰和减少铜 (II) 离子的其他物种,例如抗坏血酸, 因此降低了测试的特异性。
所有非法药物的推定颜色测试都是基于分析员的颜色知觉的一种主观形式。这里提出的颜色测试协议是特别简单的, 因为只有一个颜色变化指示合成 cathinone 的存在。这是不同于许多一般的筛选颜色测试, 买得起几种不同的色调取决于药物的礼物。
本文介绍了一个有用的和新颖的协议推定建议存在的合成 cathinones 在缴获的材料之前, 验证性的分析。通常使用的颜色测试试剂不能承受铜试剂试剂所提供的所需的特异性。最常用的一般筛选颜色测试试剂, 侯爵, 已被证明为许多合成 cathinones19的负面结果。虽然 Liebermann 的试剂确实与 cathinones 反应, 但它也与其他非法材料发生反应, 包括许多合成大麻20。
本议定书适用于法医化验所, 采用推定检验检出样本。试剂解决方案是高度稳定的, 而且协议本身特别容易遵循。

非法药物市场的运作与传统业务相似, 继续发展并适应不断变化的市场。现代技术的进步, 特别是在全球范围内, 强大的通信的激增, 通过暗网1和用户之间通过在线论坛2的广泛知识共享而增加了在线购买。与化学的进步相结合, 新的精神活性物质 (NPS) 的迅速出现, 给国际和国家药物管制带来了严重的挑战。
NPS 是有潜在危险的滥用药物, 对国际管制下的药物有类似的影响。最初作为 "法律" 的替代品销售, 在2009和 20163之间向联合国毒品和犯罪问题办事处 (禁毒办) 报告了 739 NPS。根据最近的年度报告, 在澳大利亚边境截获了一个记录数量的 NPS, 其中大多数是经过分析的, 进一步被确定为合成 cathinones4。在全球范围内, 自2010年首次报告以来, 合成 cathinones 的缉获量稳步增加, 是最常见的被缉获的 NPS5之一。
NPS 所构成的挑战主要是已发布的讨论主题6,7。法医实验室和执法人员处于劣势, 没有适当的方法在迅速出现时发现和识别核动力源。广泛的研究, 包括合成 cathinones 的检测, 在缴获的材料, 已使用气相色谱-质谱 (gc-ms)8和液相色谱-高分辨率质谱 (LC-人力资源)9验证性分析。对最小样品制备的需求不断增加, 已见红外和拉曼光谱10研究以及环境电离质谱分析, 如实时质谱直接分析 (DART-MS)11,12. 在该领域对快速、敏感的分析的需要也看到了将纸喷雾电离质谱 (PSI) 纳入到便携式设备中, 供执法人员13使用。许多仪器技术提供了验证性的分析与敏感的检测和定量的结果。但是, 对于高通量分析, 由于样品的准备、运行时间和仪器的培训和维护, 它们可能会耗费时间。
假定的颜色测试旨在建议在测试示例14中存在或缺少某些药物类。被缉获药物分析科学工作组 (SWGDRUG) 将颜色测试归类为最低的辨别力技术, 同时使用紫外光谱和免疫15。但是, 与其他技术相比, 执法部门和其他安全人员仍然广泛雇用他们, 以大大降低成本提供迅速的结果。彩色斑点测试方法所提供的主要优势是能够使用便携式测试套件在现场执行。
颜色测试的选择性取决于测试试剂与药物类之间发生的个别化学反应, 从而产生颜色变化。目前的推定测试协议缺乏检测合成 cathinones 的特殊测试;通常使用的试剂缺乏特异性和含有有害物质。其他推荐试剂尚未在大量可能的合成 cathinone 物质上进行筛选16。
这项工作的目的是提出一个简单的颜色测试协议, 可以很容易地使用的有关各方的初步筛选的合成 cathinones 在未知成分的非法物质。有关各方将包括执法部门、边防保护机构、法医实验室和其他有关安全人员。所提出的方法采用电子接受铜络合物试剂和富电子合成 cathinone 药物分子之间的还原氧化反应。使用这些化学方法开发, 你可以应用它们的形式推定颜色测试, 建议存在的合成 cathinones。

color spot test as a presumptive tool for the rapid detection of synthetic cathinones

合成 cathinones 是一大类新的精神活性物质 (NPS), 越来越普遍的药物缉获由执法和其他边境保护机构在全球范围内。颜色测试是一种推定的识别技术, 它使用快速而不复杂的化学方法来表示某一特定药物类别的存在或缺失。由于其相对较近的出现, 目前尚不具备对合成 cathinones 的具体鉴定的颜色测试。在这项研究中, 我们引入了一个协议的推定识别的合成 cathinones, 采用三水试剂溶液: 铜 (II) 硝酸盐, 29-二甲基-110-菲咯啉 (试剂) 和醋酸钠。将疑似药物的小针头大小 (大约 0.1-0.2 毫克) 添加到瓷斑板的井中, 然后在加热板上依次添加滴。在10分钟后, 从非常浅的蓝色到黄橙色的颜色变化表明可能存在的合成 cathinones。在法医实验室中, 这种高度稳定和特异的试验试剂有可能用于推定筛选未知样品, 用于合成 cathinones。然而, 对颜色变化结果的额外加热步骤的滋扰限制了测试的实验室应用, 并降低了容易翻译到现场测试的可能性。

通过几项研究验证了测试协议, 其结果在利et al.中进行了描述17. 颜色测试方法可以通过从浅蓝色到橙色 (图 1) 的颜色变化, 推定检测未知样品中的合成 cathinones。在加热周期后发生的黄色和橙色变化被认为是阳性测试结果和任何其他颜色变化, 包括非常微弱的黄色或在 heatingare 被视为负数之前发生的变化 (表 1)。
该议定书已适用于44合成 cathinone 类似物, 44 其他非法药物, 和36杂粉和切割剂在以前发表的工作17。在补充文件 1中总结了这些物质所经历的颜色变化。这些研究表明, 该协议的成功, 在推定识别存在的合成 cathinones。测试协议显示了一个89% 真实的阳性测试率和假阳性率为10%。图 2中说明了具有代表性的阳性测试结果,图 3提供了典型的负测试结果。此测试协议还可以成功地识别包含多个化合物 (图 4) 的混合物中的合成 cathinones 的存在。这是一个重要的结果, 表明它的适用性, 现实世界的样品。
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/57045/57045fig1.jpg"> 图 1: 在瓷斑板上执行的颜色测试协议的代表性结果.(A)颜色仅与试剂 (空白控件) 保持淡蓝色。(B)黄橙色变化与合成 cathinone, 4-methylmethcathinone HCl (正控制)。<a href="//cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/57045/57045fig1large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/57045/57045fig2.jpg"> 图 2: 在瓷斑板上执行的颜色测试协议具有代表性的阳性结果.在一个积极的结果中看到的颜色范围是由于不同的抗氧化能力和溶解度的化合物。(A)黄橙色变化与合成 cathinone, n, n-dimethylcathinone HCl (真阳性)。(B)浅黄色-橙色的颜色变化与合成 cathinone, 34-dimethylmethcathinone HCl (真阳性)。(C)浅色橙色的颜色随边缘的绿色环而变化, 合成 cathinone, 24, 5-trimethylmethcathinone HCl (真阳性)。(D)黄颜色变化与哌嗪模拟, 1-[3-三氟甲基苯基] 哌嗪 (TFMPP) HCl (假阳性)。<a href="//cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/57045/57045fig2large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/57045/57045fig3.jpg"> 图 3: 在瓷斑板上执行的颜色测试协议的代表性阴性结果。(A)淡绿色变色与合成 cathinone, 34-二-α-pyrrolidinobutiophenone (MDPBP) HCl (假阴性)。(B)蓝颜色变化与杂粉, 甘氨酸 (真阴性)。(C)橙色变色与药物前体, 34-3,4--2-丙酮 (MDP2P) 发生在加热前 (真阴性)。(D)颜色保持淡蓝色, 苯丙胺硫酸盐 (真阴性)。<a href="//cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/57045/57045fig3large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/57045/57045fig4.jpg"> 图 4: 对化合物混合物执行颜色测试协议的代表性结果。(a)黄橙颜色的变化与 4-methylmethcathinone 盐酸和麻黄碱混合物. (B)黄色-橙色的颜色变化, 混合 4-methylmethcathinone hcl 和 4-fluoromethcathinone (4-固定) hcl.<a href="//cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/57045/57045fig4large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<img alt="Table" class="xfigimg" src="/files/ftp_upload/57045/57045table1.jpg"> 表 1: 使用颜色测试协议观察到的颜色更改将所提出的铜-试剂色测试协议应用于124种不同的物质, 并记录了颜色的变化。黄色和橙色表示一个正的测试结果, 而任何其他颜色则报告为负结果。
补充文件1。基板的颜色测试结果。<a href="https://cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/57045/Supplementary_material.xlsx">请单击此处下载此文件.</a>

Watch this Scientific Journal Video about Color Spot Test As a Presumptive Tool for the Rapid Detection of Synthetic Cathinones at JoVE.com

Color Spot Test As a Presumptive Tool for the Rapid Detection of Synthetic Cathinones

色斑试验作为合成 Cathinones 快速检测的推定工具

在这里, 我们提出了一个简单的, 廉价的, 选择性化学斑点测试协议, 以检测合成 cathinones, 一类新的精神活性物质。该议定书适用于遇到非法材料的各个执法领域。

Synthetic cathinones are a large class of new psychoactive substances (NPS) that are increasingly prevalent in drug seizures made by law enforcement and ...

color-spot-test-as-presumptive-tool-for-rapid-detection-synthetic

Nanyang Technological University

Research

JoVE Journal

Chemistry

24.5K 次观看.  University of Technology Sydney (UTS). 在这里, 我们提出了一个简单的, 廉价的, 选择性化学斑点测试协议, 以检测合成 cathinones, 一类新的精神活性物质。该议定书适用于遇到非法材料的各个执法领域。

视频: Color Spot Test As a Presumptive Tool for the Rapid Detection of Synthetic Cathinones

Stabilizing Hepatocellular Phenotype Using Optimized Synthetic Surfaces

Currently, one of the major limitations in cell biology is maintaining differentiated cell phenotype. Biological matrices are commonly used for culturing and maintaining primary and pluripotent stem cell derived hepatocytes. While biological matrices are useful, they permit short term culture of hepatocytes, limiting their widespread application. We have attempted to overcome the limitations using a synthetic polymer coating. Polymers represent one of the broadest classes of biomaterials and possess a wide range of mechanical, physical and chemical properties, which can be fine-tuned for purpose. Importantly, such materials can be scaled to quality assured standards and display batch-to-batch consistency. This is essential if cells are to be expanded for high through-put screening in the pharmaceutical testing industry or for cellular based therapy. Polyurethanes (PUs) are one group of materials that have shown promise in cell culture. Our recent progress in optimizing a polyurethane coated surface, for long-term culture of human hepatocytes displaying stable phenotype, is presented and discussed.

This article will focus on developing polymer coated surfaces for long-term, stable culture of stem cell derived human hepatocytes.

稳定肝细胞表型采用优化合成表面

Currently, one of the major limitations in cell biology is maintaining differentiated cell phenotype. Biological matrices are commonly used for culturing ...

科研

化学

Optimization of Synthetic Proteins: Identification of Interpositional Dependencies Indicating Structurally and/or Functionally Linked Residues

Protein alignments are commonly used to evaluate the similarity of protein residues, and the derived consensus sequence used for identifying functional units (e.g., domains). Traditional consensus-building models fail to account for interpositional dependencies &#8211; functionally required covariation of residues that tend to appear simultaneously throughout evolution and across the phylogentic tree. These relationships can reveal important clues about the processes of protein folding, thermostability, and the formation of functional sites, which in turn can be used to inform the engineering of synthetic proteins. Unfortunately, these relationships essentially form sub-motifs which cannot be predicted by simple &#8220;majority rule&#8221; or even HMM-based consensus models, and the result can be a biologically invalid &#8220;consensus&#8221; which is not only never seen in nature but is less viable than any extant protein. We have developed a visual analytics tool, StickWRLD, which creates an interactive 3D representation of a protein alignment and clearly displays covarying residues. The user has the ability to pan and zoom, as well as dynamically change the statistical threshold underlying the identification of covariants. StickWRLD has previously been successfully used to identify functionally-required covarying residues in proteins such as Adenylate Kinase and in DNA sequences such as endonuclease target sites.

Synthetic protein sequences based on consensus motifs typically ignore co-evolving residues, that imply interpositional dependencies (IPDs). IPDs can be essential to activity, and designs that disregard them may result in suboptimal results. This protocol uses StickWRLD to identify IPDs and help inform rational protein design, resulting in more efficient results.

优化合成蛋白质:Interpositional依赖性的鉴定指示在结构和/或功能性连接的残留

Protein alignments are commonly used to evaluate the similarity of protein residues, and the derived consensus sequence used for identifying functional ...

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.

基于过滤器的表面增强拉曼光谱检测方法的化学污染物快速检测

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

HKUST-1 as a Heterogeneous Catalyst for the Synthesis of Vanillin

Vanillin (4-hydoxy-3-methoxybenzaldehyde) is the main component of the extract of vanilla bean. The natural vanilla scent is a mixture of approximately 200 different odorant compounds in addition to vanillin. The natural extraction of vanillin (from the orchid Vanilla planifolia, Vanilla tahitiensis and Vanilla pompon) represents only 1% of the worldwide production and since this process is expensive and very long, the rest of the production of vanillin is synthesized. Many biotechnological approaches can be used for the synthesis of vanillin from lignin, phenolic stilbenes, isoeugenol, eugenol, guaicol, etc., with the disadvantage of harming the environment since these processes use strong oxidizing agents and toxic solvents. Thus, eco-friendly alternatives on the production of vanillin are very desirable and thus, under current investigation. Porous coordination polymers (PCPs) are a new class of highly crystalline materials that recently have been used for catalysis. HKUST-1 (Cu3(BTC)2(H2O)3, BTC = 1,3,5-benzene-tricarboxylate) is a very well known PCP which has been extensively studied as a heterogeneous catalyst. Here, we report a synthetic strategy for the production of vanillin by the oxidation of trans-ferulic acid using HKUST-1 as a catalyst.

The conversion of trans-ferulic acid to vanillin was achieved by heterogeneous catalysis. HKUST-1 was employed in this synthesis and the essential step in the catalytic process was the generation of unsaturated metal sites. Thus, when the catalyst was activated under vacuum, full vanillin conversion (yield of 95%) was obtained.

科大-1作为香兰素的合成的非均相催化剂

Vanillin (4-hydoxy-3-methoxybenzaldehyde) is the main component of the extract of vanilla bean. The natural vanilla scent is a mixture of approximately ...

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.

利用毛细管电泳从植物组织量化有机酸:一个测试用例检查<em&gt;小粒种咖啡</em&gt;种子

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

NMR Spectroscopy as a Robust Tool for the Rapid Evaluation of the Lipid Profile of Fish Oil Supplements

The western diet is poor in n-3 fatty acids, therefore the consumption of fish oil supplements is recommended to increase the intake of these essential nutrients. The objective of this work is to demonstrate the qualitative and quantitative analysis of encapsulated fish oil supplements using high-resolution 1H and 13C NMR spectroscopy utilizing two different NMR instruments; a 500 MHz and an 850 MHz instrument. Both proton (1H) and carbon (13C) NMR spectra can be used for the quantitative determination of the major constituents of fish oil supplements. Quantification of the lipids in fish oil supplements is achieved through integration of the appropriate NMR signals in the relevant 1D spectra. Results obtained by 1H and 13C NMR are in good agreement with each other, despite the difference in resolution and sensitivity between the two nuclei and the two instruments. 1H NMR offers a more rapid analysis compared to 13C NMR, as the spectrum can be recorded in less than 1 min, in contrast to 13C NMR analysis, which lasts from 10 min to one hour. The 13C NMR spectrum, however, is much more informative. It can provide quantitative data for a greater number of individual fatty acids and can be used for determining the positional distribution of fatty acids on the glycerol backbone. Both nuclei can provide quantitative information in just one experiment without the need of purification or separation steps. The strength of the magnetic field mostly affects the 1H NMR spectra due to its lower resolution with respect to 13C NMR, however, even lower cost NMR instruments can be efficiently applied as a standard method by the food industry and quality control laboratories.

Here, high-resolution 1H and 13C Nuclear Magnetic Resonance (NMR) spectroscopy was used as a rapid and reliable tool for quantitative and qualitative analysis of encapsulated fish oil supplements.

核磁共振作为鱼油补充剂的血脂的快速评价一个强大的工具

The western diet is poor in n-3 fatty acids, therefore the consumption of fish oil supplements is recommended to increase the intake of these essential ...

Coulomb Explosion Imaging as a Tool to Distinguish Between Stereoisomers

This article shows how the COLTRIMS (Cold Target Recoil Ion Momentum Spectroscopy) or the "reaction microscope" technique can be used to distinguish between enantiomers (stereoisomers) of simple chiral species on the level of individual molecules. In this approach, a gaseous molecular jet of the sample expands into a vacuum chamber and intersects with femtosecond (fs) laser pulses. The high intensity of the pulses leads to fast multiple ionization, igniting a so-called Coulomb Explosion that produces several cationic (positively charged) fragments. An electrostatic field guides these cations onto time- and position-sensitive detectors. Similar to a time-of-flight mass spectrometer, the arrival time of each ion yields information on its mass. As a surplus, the electrostatic field is adjusted in a way that the emission direction and the kinetic energy after fragmentation lead to variations in the time-of-flight and in the impact position on the detector.
Each ion impact creates an electronic signal in the detector; this signal is treated by high-frequency electronics and recorded event by event by a computer. The registered data correspond to the impact times and positions. With these data, the energy and the emission direction of each fragment can be calculated. These values are related to structural properties of the molecule under investigation, i.e. to the bond lengths and relative positions of the atoms, allowing to determine molecule by molecule the handedness of simple chiral species and other isomeric features.

For small chiral species, Coulomb Explosion Imaging provides a new approach to determine the handedness of individual molecules.

作为一种工具来区分立体异构体的库仑爆炸成像

This article shows how the COLTRIMS (Cold Target Recoil Ion Momentum Spectroscopy) or the "reaction microscope" technique can be used to distinguish ...

Electrochemical Impedance Spectroscopy as a Tool for Electrochemical Rate Constant Estimation

Electrochemical impedance spectroscopy (EIS) was used for advanced characterization of organic electroactive compounds along with cyclic voltammetry (CV). In the case of fast reversible electrochemical processes, current is predominantly affected by the rate of diffusion, which is the slowest and limiting stage. EIS is a powerful technique that allows separate analysis of stages of charge transfer that have different AC frequency response. The capability of the method was used to extract the value of charge transfer resistance, which characterizes the rate of charge exchange on the electrode-solution interface. The application of this technique is broad, from biochemistry up to organic electronics. In this work, we are presenting the method of analysis of organic compounds for optoelectronic applications.

Electrochemical impedance spectroscopy (EIS) of species that undergo reversible oxidation or reduction in solution was used for determination of rate constants of oxidation or reduction.

电化学阻抗谱作为电化学速率常数估计的一种工具

Electrochemical impedance spectroscopy (EIS) was used for advanced characterization of organic electroactive compounds along with cyclic voltammetry (CV). ...

A Facile Synthetic Method to Obtain Bismuth Oxyiodide Microspheres Highly Functional for the Photocatalytic Processes of Water Depuration

Bismuth oxyhalide (BiOI) is a promising material for sunlight-driven-environmental photocatalysis. Given that the physical structure of this kind of materials is highly related to its photocatalytic performance, it is necessary to standardize the synthetic methods in order to obtain the most functional architectures and, thus, the highest photocatalytic efficiency. Here, we report a reliable route to obtain BiOI microspheres via the solvothermal process, using Bi(NO3)3 and potassium iodide (KI) as precursors, and ethylene glycol as a template. The synthesis is standardized in a 150 mL autoclave, at 126 &#176;C for 18 h. This results in 2-3 &#181;m-sized mesoporous microspheres, with a relevant specific surface area (61.3 m2/g). Shortening the reaction times in the synthesis results in amorphous structures, while higher temperatures lead to a slight increase in the porosity of the microspheres, with no effect in the photocatalytic performance. The materials are photo-active under UV-A/visible light irradiation for the degradation of the antibiotic ciprofloxacin in water. This method has demonstrated to be effective in interlaboratory tests, obtaining similar BiOI microspheres in Mexican and Chilean research groups.

This article describes a synthetic method to obtain bismuth oxyiodide microspheres, which are highly functional to perform the photocatalytic removal of organic pollutants, such as ciprofloxacin, in water under UV-A/visible light irradiation.

一种用于水降解光催化过程的高效双氧化二碘微球合成方法

Bismuth oxyhalide (BiOI) is a promising material for sunlight-driven-environmental photocatalysis. Given that the physical structure of this kind of ...

An Electrochemical Cholesteric Liquid Crystalline Device for Quick and Low-Voltage Color Modulation

We demonstrate a method for fabricating a prototype reflective display device that contains cholesteric liquid crystal (LC) as an active component. The cholesteric LC is composed of a nematic LC 4&#39;-pentyloxy-4-cyanobiphenyl (5OCB), redox-responsive chiral dopant (FcD), and a supporting electrolyte 1-ethyl-3-methylimidazolium trifluoromethanesulfonate (EMIm-OTf). The most important component is FcD. This molecule changes its helical twisting power (HTP) value in response to redox reactions. Therefore, in situ electrochemical redox reactions in the LC mixture allow for the device to change its reflection color in response to electrical stimuli. The LC mixture was introduced, by a capillary action, into a sandwich-type ITO glass cell comprising two glass slides with patterned indium tin oxide (ITO) electrodes, one of which was coated with poly(3,4-ethylenedioxythiophene)-co-poly(ethylene glycol) doped with perchlorate (PEDOT+). Upon application of +1.5 V, the reflection color of the device changed from blue (467 nm) to green (485 nm) in 0.4 s. Subsequent application of 0 V made the device recover the original blue color in 2.7 s. This device is characterized by its fastest electrical response and lowest operating voltage among any previously reported cholesteric LC device. This device could pave the way for the development of next generation reflective displays with low energy consumption rates.

A protocol for the fabrication of a reflective cholesteric liquid crystalline display device containing a redox-responsive chiral dopant allowing quick and low-voltage operation is presented.

一种用于快速和低压彩色调制的电化学胆固醇液晶器件

We demonstrate a method for fabricating a prototype reflective display device that contains cholesteric liquid crystal (LC) as an active component. The ...