Huang Yang-Zhen, Du Wen-Bin, Pan Jian-Zhang, Fang Qun
Institute of Microanalytical Systems, Chemistry Department, Zhejiang University (Zijingang Campus), Hangzhou 310058, China.
Analyst. 2008 Sep;133(9):1237-41. doi: 10.1039/b807494a. Epub 2008 Jul 24.
In this work, a microfluidic chip-based valveless flow injection analysis (FIA) system with gravity-driven flows and liquid-core waveguide (LCW) spectrometric detection was developed. Automated sample injection in the 0.3-6.4 nL range under gated injection mode was achieved by controlling the vertical position of the waste reservoir fixed on a moving platform and the residence time of the reservoir in each position, without the requirement of microvalves or electrokinetic manipulation. An integrated LCW spectrometric detection system was built on the chip by coupling a 20 mm-long Teflon AF 2400 capillary with the microchannel to function as a LCW flow cell, using a green LED as light source and a photodiode as detector. The performance of the system was demonstrated in the determination of NO(2) based on the Saltzman reaction. Linear absorbance response was obtained in the range of 0.1-20 mg L(-1) (R(2) = 0.9910), and a good reproducibility of 0.34% RSD (n = 17) was achieved.
在本工作中，开发了一种基于微流控芯片的无阀流动注射分析（FIA）系统，该系统采用重力驱动流和液芯波导（LCW）光谱检测。通过控制固定在移动平台上的废液池的垂直位置以及废液池在每个位置的停留时间，在门控进样模式下实现了0.3 - 6.4 nL范围内的自动进样，无需微阀或电动操作。通过将一根20 mm长的聚四氟乙烯AF 2400毛细管与微通道耦合，构建了一个集成在芯片上的LCW光谱检测系统，该毛细管用作LCW流通池，使用绿色发光二极管作为光源，光电二极管作为检测器。基于Saltzman反应测定NO(2)，证明了该系统的性能。在0.1 - 20 mg L(-1)范围内获得了线性吸光度响应（R(2) = 0.9910），相对标准偏差（RSD）为0.34%（n = 17），重现性良好。
