Peter Grünberg Institute, Bioelectronics (PGI-8), Forschungszentrum Jülich, Jülich, Germany.
Electrophoresis. 2012 Apr;33(8):1247-50. doi: 10.1002/elps.201100626.
An integrated detection circuitry based on a lock-in amplifier was designed for contactless conductivity determination of heavy metals. Combined with a simple-structure electrophoresis microchip, the detection system is successfully utilized for the separation and determination of various heavy metals. The influences of the running buffer and detection conditions on the response of the detector have been investigated. Six millimole 2-morpholinoethanesulfonic acid + histidine were selected as buffer for its stable baseline and high sensitivity. The best signals were recorded with a frequency of 38 kHz and 20 V(pp). The results showed that Mn(2+), Cd(2+), Co(2+), and Cu(2+) can be successfully separated and detected within 100 s by our system. The detection limits for five heavy metals (Mn(2+), Pb(2+), Cd(2+), Co(2+), and Cu(2+)) were determined to range from about 0.7 to 5.4 μM. This microchip system performs a crucial step toward the realization of a simple, inexpensive, and portable analytical device for metal analysis.
一种基于锁定放大器的集成检测电路被设计用于非接触式重金属电导率检测。结合结构简单的电泳微芯片，该检测系统成功地用于各种重金属的分离和测定。研究了运行缓冲液和检测条件对探测器响应的影响。六毫摩尔 2-吗啉乙磺酸+组氨酸被选为缓冲液，因为它具有稳定的基线和高灵敏度。在 38 kHz 和 20 V(pp)的频率下记录到最佳信号。结果表明，Mn(2+)、Cd(2+)、Co(2+)和 Cu(2+)可以在 100 s 内被我们的系统成功分离和检测。五种重金属（Mn(2+)、Pb(2+)、Cd(2+)、Co(2+)和 Cu(2+)）的检测限约为 0.7 至 5.4 μM。该微芯片系统朝着实现用于金属分析的简单、廉价和便携式分析装置迈出了关键的一步。
