Name: fabrication of a dipole-assisted solid phase extraction microchip for trace metal analysis in water samples
Uploaded: 2016-08-07T13:00:00.000+00:00
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Description: Watch this Scientific Journal Video about Fabrication of a Dipole-assisted Solid Phase Extraction Microchip for Trace Metal Analysis in Water Samples at JoVE.com

The authors would like to convey their gratitude for the technical support provided by National Synchrotron Radiation Research Center (NSRRC) (Taiwan). The authors are grateful for the financial support provided by the Ministry of Science and Technology of the Republic of China (Taiwan) and the Industrial Technology Research Institute (Taiwan).

注意！一些化学物质（ 如丙烯酰胺，1,1&#39;-二氯乙烯）在这些过程中使用的是剧毒和致癌。查阅所有相关的材料安全数据表（MSDS）后才能使用。在进行实验时，请遵循适当的安全措施。 注:除非另有说明，开展在环境温度下的所有程序在100级层流罩。 1.偶极辅助Microchip的SPE的制作<ol><li> 聚甲基丙烯酸甲酯Microchip的制备 注意:在芯片的制造协议是相似的别处描述的8。 <ol><li>绘制芯片的网络图形（ 图1（a））使用根据制造商的协议计算机辅助设计（CAD）软件。 </li><li>装入的PMMA片材上的工作表（350毫米（长）×20毫米（宽）×2毫米（高））激光微加工系统，然后集中在PMMA片材的表面上的激光源。 </li><li>通过微加工系统的控制面板中选择在CAD软件打印 ，然后将力量 ， 速度和笔模式为45％（4.5 W），13％（99.06毫米秒-1），VECT。 注:参数，如力量，速度和笔模式影响了渠道的功能提前进行了调查。的评价方法相似，由元和达沙17在本研究中所选择的参数提议被用来机适应适当的信道，以导管无需复杂的学术目的。人们可以根据自己的需要选择激光加工的另一个条件。 </li><li>根据制造商的协议打印由该激光微加工系统的绘制图案，然后机聚甲基丙烯酸甲酯片。 图1（b） </强&gt;显示制造微芯片的布局图图1（c）显示该加工板的横截面的照片。 使用激光系统时避免因暴露于激光辐射严重的眼损伤注意！佩戴护目镜。适当的排气系统，是因为激光加工在生产烟雾/烟雾的建议。 </li><li>钻头三个1/16英寸的样品入口，缓冲器入口和在底板洗脱液入口和一个用于在盖板图1汇合出口直径接入孔（b）中 。 注意！避免在加工过程与钻头体接触，以防止人身伤害。戴手套钻孔时被禁止。 </li><li>通过10分钟的超声振荡器浸入加工板成1升的0.1％在1升烧杯（重量/体积）十二烷基硫酸钠（SDS）的溶液在搅拌。 </li><li>更换SDS水溶液W第i个去离子水，并通过10分钟的超声振荡器搅拌。 </li><li>用新的替换剩余的DI H 2 O和然后通过超声波振荡器浸入加工板在1L的去离子水中2 O搅拌10分钟。之后，干燥氮气的轻柔气流2分钟各清洗板。 </li><li>对齐用肉眼在两个加工板，然后通过使用粘合剂夹夹着两个玻璃板之间的两个板。 </li><li>接合在压缩下两个板在105℃下30分钟。 </li><li>酷三明治到环境温度，然后取出长尾夹和玻璃板。 </li><li>刀片1 / 16-英寸外径的聚（醚醚酮）（PEEK）管子插入通道孔，然后用双组分环氧系粘合剂固定导管。 </li><li>干燥在常温下的粘接剂12小时。 </li></ol></li><li> 聚甲基丙烯酸甲酯微芯片的通道内饰的修改 <br/&gt; 注:以下部分是指用细微的修改发表程序8,18,19 <ol><li>递送在100微升min的流速的饱和氢氧化钠（NaOH）溶液-通过蠕动泵1到微芯片12小时（72毫升总输送量）。 </li><li>除去残留的溶液中，然后冲洗用DI H 2澳通道内以100微升min的流速-经30分钟（3毫升总递送体积）蠕动泵1。 </li><li>除去残留的去离子H 2 O和然后在100微升min的流速提供0.5％（体积/体积）硝酸（HNO 3）溶液倒入微芯片-经由蠕动泵1 30分钟（3毫升总输送量）。 </li><li>除去残留的溶液中，然后传送一个50％（重量/体积）丙烯酰胺溶液到在100微升min的流速在黑暗中的微芯片- 1 VIA蠕动泵8小时（48毫升总交付量）。 </li><li>除去残留的溶液中，然后冲洗用DI H 2澳通道内以100微升min的流速-经30分钟（3毫升总递送体积）蠕动泵1。 </li><li>空气泵除去残留去离子水中2 O用蠕动泵再涂微芯片具有一个内部的内置光掩模允许提取通道的所需的区域进行曝光。 注:在内部建光掩模由黑色纸（114毫米（长）×22毫米（宽））包含一个开放的窗口（94毫米（长）×2 mm（宽））允许所需的区域提取通道的要暴露于光。 </li><li>在CL-SPE含形成溶液的制备<ol><li>冲洗用乙醇金额至少有三个墨盒的卷抑制剂去除固相萃取柱。 </li><li>冲洗墨盒1,1&#39;-二氯乙烯达在使用前至少有三个墨盒的卷。 </li><li>通过1毫升1,1&#39;-二氯乙烯的经处理过的暗盒，然后收集在一个样品瓶包裹在铝箔的级分（20ml）中。 </li><li>添加491微升1,1&#39;-二氯乙烯到含有12毫克的2,2&#39;-偶氮二异丁腈（AIBN），3.18毫升乙醇溶液中，并在100毫升的玻璃瓶1.65毫升己烷。 </li></ol></li><li>通过注射器注射填充与含氯-SPE形成溶液（约200微升）的芯片信道，然后暴露的微芯片，以紫外（UV 365）与365nm的最大发射波长照射10分钟（光强度〜2.65毫瓦厘米-2）。 注意！建议，因为紫外线照射在生产臭氧的适当的排气系统。 </li><li>更换新鲜含CL-SPE形成溶液（约200微升）用注射器仁济残留溶液ction并且把微芯片再次紫外线照射365 10分钟（光照强度〜2.65毫瓦厘米-2）。 </li><li>重复步骤1.2.9 18倍。 </li><li>通过30分钟（3毫升总投放量），蠕动泵1 -冲洗以100微升min的流速用乙醇通道内部。删除与蠕动泵的残留溶液后，存储在一个拉链袋为后续使用制造微芯片。 </li></ol></li></ol> 2.修改PMMA表面验证<ol><li> 接触角分析 <ol><li>切有机玻璃片（350毫米（长）×20毫米（宽）×2毫米（高））转换成聚甲基丙烯酸甲酯基底（50毫米（长）×20毫米（宽）×2毫米（高））的激光微加工系统。 </li><li>浸泡在饱和NaOH溶液40毫升聚甲基丙烯酸甲酯基底在50毫升锥形管，然后通过一个摇床上搅拌所得的混合物12小时。 </li><li>去除残留的溶液，然后用清水冲洗在P用40ml去离子H 2 O的MMA基板</li><li>沉浸在40毫升去离子水中2 O的PMMA基片，然后通过一个摇床上搅拌所得的混合物30分钟。 </li><li>除去残留的去离子H 2 O浸入的PMMA基板在40毫升0.5％（体积/体积）HNO 3溶液中，然后通过一个摇床上搅拌所得的混合物30分钟。 </li><li>除去残留的溶液。浸入的PMMA基板在40毫升的50％（重量/体积）丙烯酰胺溶液中，然后通过一个摇床上搅动所得的混合物在黑暗中8小时。 </li><li>去除残留的溶液中，然后冲洗用40毫升DI H 2 O的PMMA基板</li><li>浸入的PMMA基板在40毫升去离子水中2 O中，然后通过一个摇床上搅拌所得的混合物30分钟。 </li><li>除去残留的去离子H 2 O和然后干燥氮气的轻柔气流2分钟每PMMA衬底。 </li><li>编制CL-SPE含形成液<ol><li>冲洗用乙醇金额至少有三个墨盒的卷抑制剂去除固相萃取柱。 </li><li>同花顺1,1&#39;-二氯乙烯达在使用前至少三盒，卷盒。 </li><li>通过6毫升1,1&#39;-二氯乙烯的经处理过的暗盒，然后收集在一个样品瓶包裹在铝箔的级分（20ml）中。 </li><li>添加4.91毫升1,1&#39;-二氯乙烯到含有120毫克AIBN，31.8mmol毫升乙醇，并且在100-ml玻璃瓶16.5毫升己烷的溶液中。 </li></ol></li><li>敷2毫升含Cl--SPE形成溶液到PMMA基板的表面，然后暴露衬底于UV 365照射10分钟（光强度〜2.65毫瓦厘米-2）。 注意！建议，因为紫外线照射在生产臭氧的适当的排气系统。 </li><li>更换残留SOLU化用2ml新鲜的含氯-SPE形成溶液，然后暴露在基片再次UV 365照射10分钟（光强度〜2.65毫瓦厘米-2）。 </li><li>重复步骤2.1.12 18倍。 </li><li>除去残留的溶液中，然后在50毫升锥形管用40ml乙醇冲洗的PMMA基板。 </li><li>去除残留的溶液中，然后冲洗用40毫升DI H 2 O的PMMA基板</li><li>除去残留的去离子H 2 O和然后干燥氮气的轻柔气流2分钟每PMMA衬底。 </li><li>下降5微升去离子水中2 O到PMMA基材和通过根据制造商的协议的接触角计测定的接触角。 注意:使用三个重复测量值的平均值，以确定在每一种情况下报道的接触角。 </li></ol></li><li> 激光烧蚀（LA）-Inductively耦合等离子体质谱仪（ICP-MS）分析&lt;/ STRONG&gt; <ol><li>通过研钵和研杵研磨将8g PMMA珠成聚甲基丙烯酸甲酯粉末。 </li><li>浸泡在饱和NaOH溶液40毫升聚甲基丙烯酸甲酯粉末，在50-ml锥形管中，然后通过一个摇床上搅拌所得的混合物12小时。 </li><li>用5毫升的提示删除由数字吸管残留溶液，再用清水冲洗用40毫升DI H 2 O的PMMA粉末</li><li>沉浸在40毫升去离子水中2 O的聚甲基丙烯酸甲酯粉末，然后通过一个摇床上搅拌所得的混合物30分钟。 </li><li>除去残留的去离子H 2 O浸入聚甲基丙烯酸甲酯粉末在40毫升的0.5％（体积/体积）HNO 3溶液中，然后通过一个摇床上搅拌所得的混合物30分钟。 </li><li>除去残留的溶液。浸入聚甲基丙烯酸甲酯粉末在40毫升的50％（重量/体积）丙烯酰胺溶液中，然后通过一个摇床上搅动所得的混合物在黑暗中8小时。 </li><li>去除残留的溶液中，然后冲洗PMMA粉末机智ħ将40ml二H 2 O的</li><li>浸入聚甲基丙烯酸甲酯粉末在40毫升去离子水中2 O中，然后通过一个摇床上搅拌所得的混合物30分钟。 </li><li>除去残留的去离子H 2 O和然后在60℃下烘烤的PMMA粉末8小时。 </li><li>在CL-SPE含形成溶液的制备<ol><li>冲洗用乙醇金额至少有三个墨盒的卷抑制剂去除固相萃取柱。 </li><li>同花顺1,1&#39;-二氯乙烯达在使用前至少三盒，卷盒。 </li><li>通过16毫升1,1&#39;-二氯乙烯通过处理卡盒，然后收集在用铝箔包裹的试样小瓶（20毫升）的分数。 </li><li>添加14.73毫升1,1&#39;-二氯乙烯到含有360毫克AIBN 95.4毫升乙醇，和49.5毫升己烷在250毫升的玻璃瓶的溶液。 </li></ol></li><li>在6毫升含CL-SPE形成液混合PMMA粉末50-ml锥形管中，并同样转将1ml混合物从锥形管在24孔组织培养板六个孔中。 </li><li>封面用PMMA板组织培养板，然后暴露组织培养板在紫外线照射365 10分钟（光照强度〜2.65毫瓦厘米-2）。 注意！建议，因为紫外线照射在生产臭氧的适当的排气系统。 </li><li>替换用1ml的每个的新鲜含Cl--SPE形成溶液的残留溶液以及然后暴露组织培养板再次UV 365照射10分钟（光强度〜2.65毫瓦厘米-2）。 </li><li>重复步骤2.2.13 18倍。 </li><li>除去残留的溶液中，然后在每一个用1ml乙醇冲洗的PMMA粉末很好。 </li><li>除去残留的溶液中，然后在每一个1毫升的DI H 2 O冲洗的PMMA粉末以及</li><li>除去残留的去离子水中&lt;子&gt; 2 O，然后在60℃下烘烤的PMMA粉末8小时。 </li><li>经由液压机压缩干燥粉末（1克）为粒料，然后通过LA-ICP-MS系统测量为氯的信号。 注意:在m为氯的信号/ Z 35被选定为植入的C-Cl残基的一个指标。 一个193-nm激光用作消融源。 能源 ， 通量 ， 光斑尺寸 ，和重复率分别设定为75％，8.85Ĵ厘米-2，100微米，5赫兹。被要求至少有7个为每个结果重复测量。 LA-ICP-MS分析程序是指在别处发表的程序。20 </li></ol></li><li> 拉曼光谱分析 <ol><li>从步骤2.2.1执行协议步骤2.2.17。 </li><li>经由液压机压缩干燥粉末（1克）为粒料，然后用拉曼光谱仪采取的光谱。 注:使用100毫瓦的最大激光功率作为激发源的780纳米激光线。使用拉曼光谱范围从550至900厘米的区域-1调查的C-Cl残基，以聚甲基丙烯酸甲酯的附件。 </li></ol></li></ol> 3.偶极辅助SPE反应的表征<ol><li>从步骤2.2.1执行协议步骤2.2.17。 </li><li>在5毫升的20％（重量/体积）硝酸锰四水合物（锰（NO 3）2 4H 2 O） 的溶液浸入0.5克PMMA粉末，然后同样将所得的混合物用5毫升40毫马来酸盐缓冲溶液混合。 </li><li>通过使用纯的HNO 3水溶液调节所得混合物的pH至8，然后再通过一个摇床上搅拌混合物1小时。 </li><li>除去残留的溶液中，然后在60℃下烘烤的PMMA粉末8小时。在15-ml锥形管包裹在铝箔的X射线absor存储粉末ption近边结构（XANES）分析。 注:锰K边XANES谱用07A和国家同步辐射研究中心（NSRRC，台湾新竹）的光束线17C1收集。电子储存环用的1.5电子伏特的能量和100-200毫安的电流操作。的Si（​​111）双晶单色用于提供与第1能量高度单色光子束15千电子伏特和解析力（E /ΔE）高达5,000.The光子能量是通过使用公知的Mn的Mn标准物校准的K在6539.0电子伏特边吸收拐点。 6530和6,570伏特之间被用来研究对所提出的固相萃取反应表征偶极离子相互作用在该区域的Mn K边缘XANES光谱。 </li></ol>

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The authors have nothing to disclose.

为偶极辅助SPE微芯片的制备的详细程序上面作了介绍。在本节中，修改协议的关于在PMMA的C-Cl残基和含氯-PMMA，将其用作用于痕量金属离子的测定提取介质的可行性的植入的效用，是评估一步一步的。对于表面验证目的，样品类型是其与分析仪器的兼容性的基础上选择的。换句话说，该类型通过类似的方法制备的测试样品在根据分析仪器的要求进行了测定。例如，使用一个衬底型样品的接触角的测定，而被用于对LA-ICP-MS，拉曼分光的粉末包装型样品，和XANES分析。 最初，以监测由所述化学官能武官发生变化所提出的程序期间d，来聚甲基丙烯酸甲酯的表面上，对应于每个步骤进行所得产物的接触角分析（ 图2）。如显示在图2中，接触角的变化清楚地表明，在修改的程序发生表面的变化，而 ​​测定该最终产物是在协议与先前报告的结果为80.3°±0.43°的接触角。21 此外，关于改性的PMMA的C-Cl残基的存在通过LA-ICP-MS分析也证实。与由烧蚀天然PMMA获得的结果相比，被烧蚀具有C-Cl残基改性聚甲基丙烯酸甲酯expectably观察氯不同信号（ 图3的（a））。 拉曼光谱收集用于进一步验证的C-Cl残基，以聚甲基丙烯酸甲酯的附件。如图Figu再如图3（b），682 -1和718 -1中的改性的PMMA的光谱中观察到与四氯化碳2不对称伸缩振动有关的两个特征峰，并与由Willis 等人报道的结果，在合理的良好的一致性22和亨德拉等人 23换言之，该C-Cl残基，以聚甲基丙烯酸甲酯的附件可以成功地修改后实现的。 此外，为了澄清这项研究提出了萃取机理，被采用的XANES分析。如在图4所示，高度电负性的C-Cl残基和带正电的金属离子之间的相互作用可以由主导吸收边缘在对应于与锰2+离子处理的改性的PMMA的XANES光谱的存在来确认。因此，偶极 - 静电相互作用将确实应用到TR片上提取王牌金属分析。在台湾从两江收集的水样品的详细分析结果已在其他地方描述。16 据我们所知，这是利用一种创新的工作战略的痕量金属离子的测定芯片上SPE反应的第一次尝试，并与其他芯片SPE技术相比，开发的设备是显著耐用（ 即 160多个作品的分析可以不显著恶化的提取效率方面实现）。然而，因为这样的取出机构主要依赖于高度电负性的C-Cl残基和带正电的金属离子之间的相互作用，所提出的技术预计是不适于带负电荷的物质的提取为止。

从环境管理和污染防治的观点，微量金属污染严重或毒性问题是一个世界性的问题。芯片样品前处理技术已被广泛接受为重点，以处理和分析通过基于芯片的平台实际样品的成功，因为原料样品中意外并存的化学物质往往妨碍痕迹量存在分析物的准确测定一个适当的1在现有的技术中，芯片上的固相萃取（SPE）是特别受欢迎的痕量金属分析，因为该技术允许样品净化，也可以同时进行分析物富集是用于从复杂的盐基质金属离子的隔离非常有用的。 2,3 片上SPE技术用于痕量元素测定的进步一直在稳步发展。在创业初期，T他SPE通过加载市售的树脂进入微通道构造树脂填充的SPE单元制备芯片。4-7这偶尔需要的分析物进行衍生，以使金属离子转变成树脂保持性形式4的另一种方法用于基于芯片的SPE装置的制备是利用芯片信道作为SPE吸附剂微量金属的简单表面改性后的收集。8最近几年，涉及磁性纳米颗粒（的MNP）和特定化学物质的掺入一种新兴趋势包含能够金属离子的有效保留的官能团。在对比的商业树脂，所述的MNP被修改以如后它们被包装到微通道与外部磁场的t借助于γ巯基（γ-MPTS）9和氨基苄乙二胺四乙酸（ABEDTA）10化合物Ø实现金属离子的选择性提取。 虽然在芯片上SPE技术的发展显著的进步已经见证，报道的技术通常功能的基础上无论是离子交换或螯合作用。使用的技术，如这些具有需要不可避免操作程序，包括那些有空调，洗衣机，或再生相关联，以保持所述分析性能的缺点。不幸的是，需要额外的操作程序，不仅扩展了对每个分析所需要的时间，而且造成的风险高空白值和复制的结果。11因此，对于芯片SPE技术合作战略的选择是当务之急痕量金属分析。 1993年，瓦特和Chehimi 12发现，金属离子具有朝向聚合材料滞留倾向，多数分析物有效地保留在氯（Cl）的-containi纳克聚合物材料，聚（氯乙烯）（PVC），除了钠离子。因此，在2002年，Eboatu 等 13还对一些有毒金属从PVC的解决方案封存的报道。因为这表明含CL-的表现分析物富集和盐基体消除优异性能的聚合物材料，用CL-含SPE功能的基于芯片的装置被认为是一种新型的芯片固相萃取技术的发展，为确定一个有吸引力的战略的微量金属离子。考虑材料的特性，如易于制造的，希望的化学/机械特性，并且光学透明度，14,15这项研究了聚甲基丙烯酸甲酯（PMMA）的优点来制造微型装置。然后，将含有氯-SPE的功能植入用于痕量金属离子的测定的新颖的片SPE技术的发展所制造的装置。16 - [Remarkably，关于在信道内的高度电负性的C-Cl残基和带正电的金属离子之间的偶极子 - 离子相互作用的创新提取机构的依赖，使得有可能避免在一般芯片上的SPE程序所采取的措施，从而导致任污染显着减少因使用过量的试剂或归因于额外的步骤的劳力。在这方面的贡献提供的协议将使来自不同背景的研究人员制造了他们的工作偶极辅助SPE微芯片。对于所制造的微芯片详细的表征程序被描述为良好。

<table><tbody><tr><td>AutoCAD</td><td>Autodesk</td><td>N/A</td><td>http://www.autodesk.com/education/free-software/autocad</td></tr><tr><td>Poly(methyl methacrylate) (PMMA) sheet</td><td>Kun Quan Engineering Plastics</td><td>N/A</td><td>350 mm (L) x 20 mm (W) x 2 mm (H). The glass transition temperature (Tg) of PMMA sheets is ranged from 102&amp;ndash;110 &amp;deg;C. The UV transmittance of the PMMA at 365 nm is 91.2%.</td></tr><tr><td>Micromachining system</td><td>Laser Life</td><td>LES-10</td><td>Maximum laser power: 10 W. Maximium engraving speed: 762 mm sec&lt;sup&gt;&amp;minus;1&lt;/sup&gt;.</td></tr><tr><td>High-resolution optical microscope</td><td>Ching Hsing Computer-Tech</td><td>FS-230</td><td></td></tr><tr><td>Power Image Analysis system (PIA)</td><td>Ching Hsing Computer-Tech</td><td>PIA V16.1</td><td></td></tr><tr><td>Multi drilling machines</td><td>N/A</td><td>LT-848</td><td></td></tr><tr><td>Deionized water (D. I. H&lt;sub&gt;2&lt;/sub&gt;O)</td><td>Millipore</td><td>Milli-Q Integral 5 System</td><td></td></tr><tr><td>Sodium dodecyl sulfate (SDS)</td><td>J. T. Baker</td><td>4095-04</td><td></td></tr><tr><td>Ultrasound oscillator</td><td>Elma</td><td>Transsonic Digital</td><td></td></tr><tr><td>Glass board</td><td>N/A</td><td>N/A</td><td>160 mm (L) x 35 mm (W) x 2 mm (H); fragile</td></tr><tr><td>Binder clip</td><td>SDI</td><td>0234T-1</td><td>http://stationery.sdi.com.tw/product_detail.php?Key=322&amp;amp;cID=55&amp;amp;uID=6</td></tr><tr><td>Precision oven</td><td>Yeong Shin</td><td>DK-45</td><td></td></tr><tr><td>Poly(etheretherketone) (PEEK) tube</td><td>VICI</td><td>JR-T-6002 (0.5 mm i.d.); JR-T-6001 (0.25 mm i.d.)</td><td></td></tr><tr><td>Polymer tubing&amp;nbsp; cutter</td><td>Upchurch Scientific</td><td>A-327</td><td></td></tr><tr><td>Two-component epoxy-based adhesive</td><td>Richwang</td><td>N/A</td><td>Skin irritative. The major components are an epoxy resin and a hardener.</td></tr><tr><td>Peristaltic pump</td><td>Gilson</td><td>Minipuls 3</td><td></td></tr><tr><td>Peristaltic tube</td><td>Gilson</td><td>F117934</td><td></td></tr><tr><td>Sodium hydroxide (NaOH)</td><td>Sigma&amp;ndash;Aldrich</td><td>30620</td><td></td></tr><tr><td>Nitric acid (HNO&lt;sub&gt;3&lt;/sub&gt;)</td><td>J. T. Baker</td><td>959834</td><td></td></tr><tr><td>Acrylamide (prop-2-enamide, C&lt;sub&gt;3&lt;/sub&gt;H&lt;sub&gt;5&lt;/sub&gt;NO)</td><td>Sigma&amp;ndash;Aldrich</td><td>A8887</td><td>Acutely toxic and carcinogenic</td></tr><tr><td>In-house-built photomask</td><td>N/A</td><td>N/A</td><td>The in-house-built photomask was made of a black paper (114 mm (L) &amp;times; 22 mm (W)) that contained an open window (94 mm (L) &amp;times; 2 mm (W)) allowing the desired region</td></tr><tr><td>1,1-Dichloroethylene</td><td>Sigma&amp;ndash;Aldrich</td><td>163032</td><td>Acutely toxic and carcinogenic</td></tr><tr><td>Cartridge</td><td>Dikma</td><td>ProElut AL-B&amp;nbsp;</td><td></td></tr><tr><td>2,2-Azobisisobutyronitrile (AIBN, C&lt;sub&gt;8&lt;/sub&gt;H&lt;sub&gt;12&lt;/sub&gt;N&lt;sub&gt;4&lt;/sub&gt;)</td><td>Showa Chemical&amp;nbsp;</td><td>0159-2130</td><td></td></tr><tr><td>Ethanol</td><td>Sigma&amp;ndash;Aldrich</td><td>32221</td><td></td></tr><tr><td>Hexanes (C&lt;sub&gt;6&lt;/sub&gt;H&lt;sub&gt;14&lt;/sub&gt;)</td><td>Millinckrodt Chemical</td><td>5189-08</td><td></td></tr><tr><td>In-house-built irradiation system</td><td>Great Lighting (UV-A lamp)</td><td>N/A</td><td>An opaque box with an UV-A lamp (40 W, maximum emission at 365 nm)</td></tr><tr><td>Glass vial</td><td>Yeong Shin</td><td>132300019</td><td>Fragile</td></tr><tr><td>Aluminum foil</td><td>Diamond</td><td>N/A</td><td></td></tr><tr><td>Conical tubes with screw caps</td><td>labcon</td><td>3181-345-008 (50 mL); 3131-345-008 (15 mL)</td><td></td></tr><tr><td>Rocking shaker</td><td>TKS</td><td>RS-01</td><td></td></tr><tr><td>Contact angle meter</td><td>First Ten Angstroms</td><td>FTA 125</td><td></td></tr><tr><td>PMMA bead</td><td>Scientific Polymer Products</td><td>037A</td><td></td></tr><tr><td>Mortar and pestle, agate&amp;nbsp;</td><td>Yeong Shin</td><td>139000004</td><td>Fragile</td></tr><tr><td>Tissue culture plate</td><td>AdvanGene Life Science Plasticware</td><td>AGC-CP-24S-50EA</td><td>24-Well, non-treated, sterilized</td></tr><tr><td>Hydraulic press</td><td>Panchum</td><td>Press-200</td><td></td></tr><tr><td>Laser ablation</td><td>New Wave Research</td><td>NWR193</td><td></td></tr><tr><td>Inductively coupled plasma-mass spectrometer</td><td>Agilent Technologies</td><td>Agilent 7500a</td><td></td></tr><tr><td>Glass bottle</td><td>DURAN</td><td>21801245 (100 mL); 21801365 (250 mL)</td><td></td></tr><tr><td>Dispersive Raman spectrometer</td><td>Thermo Fisher Scientific</td><td>Nicolet Almega XR</td><td></td></tr><tr><td>Manganese nitrate tetrahydrate (Mn(NO&lt;sub&gt;3&lt;/sub&gt;)&lt;sub&gt;2&lt;/sub&gt;&amp;times;4H&lt;sub&gt;2&lt;/sub&gt;O)</td><td>Sigma&amp;ndash;Aldrich</td><td>63547</td><td></td></tr><tr><td>Maleic acid disodium salt hydrate (C&lt;sub&gt;4&lt;/sub&gt;H&lt;sub&gt;4&lt;/sub&gt;Na&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;5&lt;/sub&gt;)</td><td>Sigma&amp;ndash;Aldrich</td><td>M9009</td><td></td></tr><tr><td>X-ray absorption near edge structure (XANES)&amp;nbsp;</td><td>N/A</td><td>N/A</td><td>The Mn K-edge XANES analyses were conducted at 07A and 17C1 beamlines of the National Synchrotron Radiation Research Center (NSRRC) in Taiwan.</td></tr></tbody></table>

fabrication of a dipole-assisted solid phase extraction microchip for trace metal analysis in water samples

本文介绍了可用于水样中痕量金属分析偶极辅助固相萃取（SPE）微芯片的制造协议。提供的基于芯片的SPE技术演进的简要概述。这之后是介绍特定的聚合物材料以及它们在SPE作用。开发一个创新的偶极辅助SPE技术中，含SPE功能的氯（Cl）溶液注入到聚（甲基丙烯酸甲酯）（PMMA）的微芯片。这里，不同的分析技术，包括接触角分析，拉曼光谱分析中，以及激光烧蚀电感耦合等离子体 - 质谱（LA-ICP-MS）的分析被雇用来验证对的C- Cl残基的植入协议的效用PMMA。的X射线吸收近边结构的分析结果（XANES）分析还凭借偶极的证实用作萃取介质中的含氯-PMMA的可行性高电负性的C-Cl残基和带正电的金属离子之间的离子相互作用。

图2描述了在聚甲基丙烯酸甲酯微芯片的流路变更手续发生反应。采用接触角分析，监测建议的程序在表面的变化。一个LA-ICP-MS系统和色散型拉曼光谱仪被雇用来验证C-C1的成功修饰部分的PMMA基板上形成（ 如图3（a），（b））的 。所提出的偶极辅助SPE反应的特点是XANES分析（ 图4）。 <img alt="图1" src="/files/ftp_upload/53500/53500fig1.jpg" /> 图1:PMMA微芯片。（ 一 ）为了制造微芯片的模式文件的快照。 （ 二 ）所制造的微芯片的布局:S，E和B代表的引入端口，用于将样品，洗脱剂，和BUF外汇储备的解决方案，分别为; O代表出口。黑色圆圈表示每个所钻的进入孔。用于引入样品和缓冲溶液的通道都形成与提取通道30°的角度。有效提取通道，其被定义为从样品和缓冲液至汇合出口的流动的会聚点的距离的长度，是94毫米。 （c）该加工板的横截面的照片。从参考转载。 16通过化学的英国皇家学会的许可。 <a href="https://www.jove.com/files/ftp_upload/53500/53500fig1large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图2" src="/files/ftp_upload/53500/53500fig2.jpg" /> 图2. 方案的PMMA微通道修改。插图photogrAPHS显示对应于序列中的所得产物的接触角。接触角是通过使用一水滴的图像来确定。被用于确定在每一种情况下报道的接触角三个重复测量的平均值。从参考转载。 16通过化学的英国皇家学会的许可。 <a href="https://www.jove.com/files/ftp_upload/53500/53500fig2large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图3" src="/files/ftp_upload/53500/53500fig3.jpg" /> 图3. 表面PMMA修饰的验证。（a）由消融二者的PMMA和聚甲基丙烯酸甲酯与C-Cl残基改性得到的信号为氯。插图示出对应于每个获得的信号的消融位置。 （ 二 ）原生拉曼光谱和修改PMMA。从参考转载。 16由许可皇家化学学会。 <a href="https://www.jove.com/files/ftp_upload/53500/53500fig3large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图4" src="/files/ftp_upload/53500/53500fig4.jpg" /> 图4. 锰K边XANES与锰 离子 离子 处理改性PMMA和PMMA修饰谱 ，修饰的PMMA的光谱是作为红线。显示的吸收光谱修饰PMMA的高度负电的C-Cl残基和锰离子的离子之间的相互作用是作为蓝线。从参考转载。 16通过化学的英国皇家学会的许可。 <a href="https://www.jove.com/files/ftp_upload/53500/53500fig4large.jpg" target="_blank">请点击此处查看该图的放大版本。</a>

Watch this Scientific Journal Video about Fabrication of a Dipole-assisted Solid Phase Extraction Microchip for Trace Metal Analysis in Water Samples at JoVE.com

Fabrication of a Dipole-assisted Solid Phase Extraction Microchip for Trace Metal Analysis in Water Samples

The fabrication protocol of a dipole-assisted solid phase extraction microchip for the trace metal analysis is presented.

水样中偶极辅助固相萃取Microchip的痕量金属分析的制作

This paper describes a fabrication protocol for a dipole-assisted solid phase extraction (SPE) microchip available for trace metal analysis in water ...

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8.6K 次观看.  National Tsing Hua University. The fabrication protocol of a dipole-assisted solid phase extraction microchip for the trace metal analysis is presented.

视频: Fabrication of a Dipole-assisted Solid Phase Extraction Microchip for Trace Metal Analysis in Water Samples

A Simple Method for Automated Solid Phase Extraction of Water Samples for Immunological Analysis of Small Pollutants

A new method for solid phase extraction (SPE) of environmental water samples is proposed. The developed prototype is cost-efficient and user friendly, and enables to perform rapid, automated and simple SPE. The pre-concentrated solution is compatible with analysis by immunoassay, with a low organic solvent content. A method is described for the extraction and pre-concentration of natural hormone 17&#946;-estradiol in 100 ml water samples. Reverse phase SPE is performed with octadecyl-silica sorbent and elution is done with 200 &#181;l of methanol 50% v/v. Eluent is diluted by adding di-water to lower the amount of methanol. After preparing manually the SPE column, the overall procedure is performed automatically within 1 hr. At the end of the process, estradiol concentration is measured by using a commercial enzyme-linked immune-sorbent assay (ELISA). 100-fold pre-concentration is achieved and the methanol content in only 10% v/v. Full recoveries of the molecule are achieved with 1 ng/L spiked de-ionized and synthetic sea water samples.

A protocol for the extraction and pre-concentration of estradiol from water samples by using an automated and miniaturized system is presented.

对水样的自动固相萃取小污染物的免疫学分析的简单方法

A new method for solid phase extraction (SPE) of environmental water samples is proposed. The developed prototype is cost-efficient and user friendly, and ...

科研

环境科学

Clean Sampling and Analysis of River and Estuarine Waters for Trace Metal Studies

Most of the trace metal concentrations in ambient waters obtained a few decades ago have been considered unreliable owing to the lack of contamination control. Developments of some techniques aiming to reduce trace metal contamination in the last couple of decades have resulted in concentrations reported now being orders of magnitude lower than those in the past. These low concentrations often necessitate preconcentration of water samples prior to instrumental analysis of samples. Since contamination can appear in all phases of trace metal analyses, including sample collection (and during preparation of sampling containers), storage and handling, pretreatments, and instrumental analysis, specific care needs to be taken in order to reduce contamination levels at all steps. The effort to develop and utilize "clean techniques" in trace metal studies allows scientists to investigate trace metal distributions and chemical and biological behavior in greater details. This advancement also provides the required accuracy and precision of trace metal data allowing for environmental conditions to be related to trace metal concentrations in aquatic environments.
This protocol that is presented here details needed materials for sample preparation, sample collection, sample pretreatment including preconcentration, and instrumental analysis. By reducing contamination throughout all phases mentioned above for trace metal analysis, much lower detection limits and thus accuracy can be achieved. The effectiveness of "clean techniques" is further demonstrated using low field blanks and good recoveries for standard reference material. The data quality that can be obtained thus enables the assessment of trace metal distributions and their relationships to environmental parameters.

Special care using "clean techniques" is required to properly collect and process water samples for trace metal studies in aquatic environments. A protocol for sampling, processing, and analytical procedures with the aim of obtaining reliable environmental monitoring data and results with high sensitivity for detailed trace metal studies is presented.

清洁取样和痕量金属研究河和河口水域分析

Most of the trace metal concentrations in ambient waters obtained a few decades ago have been considered unreliable owing to the lack of contamination ...

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.

对芯片等速电泳离子的分离和纯化核酸

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

生物工程

Detection and Recovery of Palladium, Gold and Cobalt Metals from the Urban Mine Using Novel Sensors/Adsorbents Designated with Nanoscale Wagon-wheel-shaped Pores

Developing low-cost, efficient processes for recovering and recycling palladium, gold and cobalt metals from urban mine remains a significant challenge in industrialized countries. Here, the development of optical mesosensors/adsorbents (MSAs) for efficient recognition and selective recovery of Pd(II), Au(III), and Co(II) from urban mine was achieved. A simple, general method for preparing MSAs based on using high-order mesoporous monolithic scaffolds was described. Hierarchical cubic Ia3d wagon-wheel-shaped MSAs were fabricated by anchoring chelating agents (colorants) into three-dimensional pores and micrometric particle surfaces of the mesoporous monolithic scaffolds. Findings show, for the first time, evidence of controlled optical recognition of Pd(II), Au(III), and Co(II) ions and a highly selective system for recovery of Pd(II) ions (up to ~95%) in ores and industrial wastes. Furthermore, the controlled assessment processes described herein involve evaluation of intrinsic properties (e.g., visual signal change, long-term stability, adsorption efficiency, extraordinary sensitivity, selectivity, and reusability); thus, expensive, sophisticated instruments are not required. Results show evidence that MSAs will attract worldwide attention as a promising technological means of recovering and recycling palladium, gold and cobalt metals.

Because of the importance and extensive use of palladium, gold and cobalt metals in high-technology equipment, their recovery and recycling constitute an important industrial challenge. The metal recovery system described herein is a simple, low-cost means for the effective detection, removal, and recovery of these metals from the urban mine.

检测和钯的回收，从城市矿山黄金和钴金属使用标有纳米货车车轮形的孔隙新型传感器/吸附剂

Developing low-cost, efficient processes for recovering and recycling palladium, gold and cobalt metals from urban mine remains a significant challenge in ...

工程学

Fabrication of the Thermoplastic Microfluidic Channels

In our lab, we have successfully isolated nucleic acids directly from microliter and submicroliter volumes of human blood, urine and stool using polymer/nanoparticle composite microscale lysis and solid phase extraction columns. The recovered samples are concentrated, small volume samples that are PCRable, without any additional cleanup. Here, we demonstrate how to fabricate thermoplastic microfluidic chips using hot embossing and heat sealing. Then, we demonstrate how to use in situ light directed surface grafting and polymerization through the sealed chip to form the composite solid phase columns. We demonstrate grafting and polymerization of a carbon nanotube/polymer composite column for bacterial cell lysis. We then show the lysis process followed by solid phase extraction of nucleic acids from the sample on chip using a silica/polymer composite column. The attached protocols contain detailed instructions on how to make both lysis and solid phase extraction columns.

Here we demonstrate how to fabricate thermoplastic microfluidic chips using hot embossing and heat sealing. Then we demonstrate how to use in situ light directed surface grafting and polymerization through the sealed chip to form the composite solid phase columns.

制备热塑性微流体通道

In our lab, we have successfully isolated nucleic acids directly from microliter and submicroliter volumes of human blood, urine and stool using ...

生物学

A Microfluidic Chip for the Versatile Chemical Analysis of Single Cells

We present a microfluidic device that enables the quantitative determination of intracellular biomolecules in multiple single cells in parallel. For this purpose, the cells are passively trapped in the middle of a microchamber. Upon activation of the control layer, the cell is isolated from the surrounding volume in a small chamber. The surrounding volume can then be exchanged without affecting the isolated cell. However, upon short opening and closing of the chamber, the solution in the chamber can be replaced within a few hundred milliseconds. Due to the reversibility of the chambers, the cells can be exposed to different solutions sequentially in a highly controllable fashion, e.g. for incubation, washing, and finally, cell lysis. The tightly sealed microchambers enable the retention of the lysate, minimize and control the dilution after cell lysis. Since lysis and analysis occur at the same location, high sensitivity is retained because no further dilution or loss of the analytes occurs during transport. The microchamber design therefore enables the reliable and reproducible analysis of very small copy numbers of intracellular molecules (attomoles, zeptomoles) released from individual cells. Furthermore, many microchambers can be arranged in an array format, allowing the analysis of many cells at once, given that suitable optical instruments are used for monitoring. We have already used the platform for proof-of-concept studies to analyze intracellular proteins, enzymes, cofactors and second messengers in either relative or absolute quantifiable manner.

In this article we present a microfluidic chip for single cell analysis. It allows the quantification of intracellular proteins, enzymes, cofactors, and second messengers by means of fluorescent assays or immunoassays.&#160;

一个微流控芯片单细胞的多功能化学分析

We present a microfluidic device that enables the quantitative determination of intracellular biomolecules in multiple single cells in parallel. For this ...

A Microfluidic-based Electrochemical Biochip for Label-free DNA Hybridization Analysis

Miniaturization of analytical benchtop procedures into the micro-scale provides significant advantages in regards to reaction time, cost, and integration of pre-processing steps. Utilizing these devices towards the analysis of DNA hybridization events is important because it offers a technology for real time assessment of biomarkers at the point-of-care for various diseases. However, when the device footprint decreases the dominance of various physical phenomena increases. These phenomena influence the fabrication precision and operation reliability of the device. Therefore, there is a great need to accurately fabricate and operate these devices in a reproducible manner in order to improve the overall performance. Here, we describe the protocols and the methods used for the fabrication and the operation of a microfluidic-based electrochemical biochip for accurate analysis of DNA hybridization events. The biochip is composed of two parts: a microfluidic chip with three parallel micro-channels made of polydimethylsiloxane (PDMS), and a 3 x 3 arrayed electrochemical micro-chip. The DNA hybridization events are detected using electrochemical impedance spectroscopy (EIS) analysis. The EIS analysis enables monitoring variations of the properties of the electrochemical system that are dominant at these length scales. With the ability to monitor changes of both charge transfer and diffusional resistance with the biosensor, we demonstrate the selectivity to complementary ssDNA targets, a calculated detection limit of 3.8 nM, and a 13% cross-reactivity with other non-complementary ssDNA following 20 min&#160;of incubation. This methodology can improve the performance of miniaturized devices by elucidating on the behavior of diffusion at the micro-scale regime and by enabling the study of DNA hybridization events.

We present a microfluidic-based electrochemical biochip for DNA hybridization detection. Following ssDNA probe functionalization, the specificity, sensitivity, and detection limit are studied with complementary and non-complementary ssDNA targets. Results illustrate the influence of the DNA hybridization events on the electrochemical system, with a detection limit of 3.8 nM.

微流体为基础的电化学生物芯片的无标记的DNA杂交分析

Miniaturization of analytical benchtop procedures into the micro-scale provides significant advantages in regards to reaction time, cost, and integration ...

A Microfluidic Chip for ICPMS Sample Introduction

This protocol discusses the fabrication and usage of a disposable low cost microfluidic chip as sample introduction system for inductively coupled plasma mass spectrometry (ICPMS). The chip produces monodisperse aqueous sample droplets in perfluorohexane (PFH). Size and frequency of the aqueous droplets can be varied in the range of 40 to 60 &#181;m and from 90 to 7,000&#160;Hz, respectively. The droplets are ejected from the chip with a second flow of PFH and remain intact during the ejection. A custom-built desolvation system removes the PFH and transports the droplets into the ICPMS. Here, very stable signals with a narrow intensity distribution can be measured, showing the monodispersity of the droplets. We show that the introduction system can be used to quantitatively determine iron in single bovine red blood cells. In the future, the capabilities of the introduction device can easily be extended by the integration of additional microfluidic modules.

We present a discrete droplet sample introduction system for inductively coupled plasma mass spectrometry (ICPMS). It is based on a cheap and disposable microfluidic chip that generates highly monodisperse droplets in a size range of 40&#8722;60 &#181;m at frequencies from 90 to 7,000 Hz.

微流体芯片ICPMS进样

This protocol discusses the fabrication and usage of a disposable low cost microfluidic chip as sample introduction system for inductively coupled plasma ...

A Microfluidic Platform for Precision Small-volume Sample Processing and Its Use to Size Separate Biological Particles with an Acoustic Microdevice

A major advantage of microfluidic devices is the ability to manipulate small sample volumes, thus reducing reagent waste and preserving precious sample. However, to achieve robust sample manipulation it is necessary to address device integration with the macroscale environment. To realize repeatable, sensitive particle separation with microfluidic devices, this protocol presents a complete automated and integrated microfluidic platform that enables precise processing of 0.15&#8211;1.5 ml samples using microfluidic devices. Important aspects of this system include modular device layout and robust fixtures resulting in reliable and flexible world to chip connections, and fully-automated fluid handling which accomplishes closed-loop sample collection, system cleaning and priming steps to ensure repeatable operation. Different microfluidic devices can be used interchangeably with this architecture. Here we incorporate an acoustofluidic device, detail its characterization, performance optimization, and demonstrate its use for size-separation of biological samples. By using real-time feedback during separation experiments, sample collection is optimized to conserve and concentrate sample. Although requiring the integration of multiple pieces of equipment, advantages of this architecture include the ability to process unknown samples with no additional system optimization, ease of device replacement, and precise, robust sample processing.

This protocol describes a system architecture for performing automated small volume (0.15&#8211;1.5 ml) particle separations using a microfluidic device, and discusses methods to optimize acoustofluidic device performance and operation.

微流体平台精密小批量来样加工及它的使用尺寸分离生物颗粒的声微型

A major advantage of microfluidic devices is the ability to manipulate small sample volumes, thus reducing reagent waste and preserving precious sample. ...

Fast Enzymatic Processing of Proteins for MS Detection with a Flow-through Microreactor

The vast majority of mass spectrometry (MS)-based protein analysis methods involve an enzymatic digestion step prior to detection, typically with trypsin. This step is necessary for the generation of small molecular weight peptides, generally with MW &#60; 3,000-4,000 Da, that fall within the effective scan range of mass spectrometry instrumentation. Conventional protocols involve O/N enzymatic digestion at 37 &#186;C. Recent advances have led to the development of a variety of strategies, typically involving the use of a microreactor with immobilized enzymes or of a range of complementary physical processes that reduce the time necessary for proteolytic digestion to a few minutes (e.g., microwave or high-pressure). In this work, we describe a simple and cost-effective approach that can be implemented in any laboratory for achieving fast enzymatic digestion of a protein. The protein (or protein mixture) is adsorbed on C18-bonded reversed-phase high performance liquid chromatography (HPLC) silica particles preloaded in a capillary column, and trypsin in aqueous buffer is infused over the particles for a short period of time. To enable on-line MS detection, the tryptic peptides are eluted with a solvent system with increased organic content directly in the MS ion source. This approach avoids the use of high-priced immobilized enzyme particles and does not necessitate any aid for completing the process. Protein digestion and complete sample analysis can be accomplished in less than ~3 min and ~30 min, respectively.

A quick protocol for proteolytic digestion with an in-house built flow-through tryptic microreactor coupled to an electrospray ionization (ESI) mass spectrometer is presented. The fabrication of the microreactor, the experimental setup and the data acquisition process are described.

蛋白质的MS检测快速酶法处理与流通型微反应器

The vast majority of mass spectrometry (MS)-based protein analysis methods involve an enzymatic digestion step prior to detection, typically with trypsin. ...