微流控芯片简易安培检测器的制作及对烟酰胺片中烟酰胺的测定

Fabrication of Microfluidic Chip with Simplified Amperometric Detector and Its Determination of Nicotinamide in Nicotinamide Tablets

搭建了微流控芯片简易安培检测器,并用于市售药品烟酰胺片中烟酰胺含量的测定.由碳纳米管微圆盘电极和钛管组成集成双电极,中间的碳纳米管微圆盘电极作为安培检测的工作电极,外套的钛管既作为安培检测的对极,又充当分离高压电源的地极,使其结构更加简化和微型化.优化了缓冲溶液种类、浓度,分离电压及进样时间等实验条件.结果表明,在10 mmol·L-1磷酸盐缓冲液（pH 7.8）中,进样10 s,在2.0kV电压下分离,烟酰胺在2 min内可实现较好的分离和检测,其线性范围为10～600 μmol·L-1。

A novel microfluidic chip system with simplified amperometric detector was manufacturedand used to determine nicotinamide in commercially available nicotinamide tablets. The integratedtwo-electrode in the simplified amperometric detector was comprised of a carbon - nanotubes electrodeand a titanium tube. The carbon -nanotubes electrode in the middle of the electrode was used as theworking electrode, and the titanium tube was used not only as a counter electrode of amperometric de-tection but also as the ground electrode of power source in separation. The structure of microfluidicchip system was more simplified and miniaturized. The experimental conditions, such as type andconcentration of buffer solution, separation voltage and injection time etc, were optimized. The re-suits showed that nicotinamide was separated and detected within 2 min in the buffer of 10 mmol · L-1phosphate solution（ pH 7.8） at a separation voltage of 2.0 kV and an injection time of 10 s. The cal-ibration curve of nicotinamide was linear in the range of 10 -600 μmol · L-1. The limit of detection（ LOD, S/N = 3 ） reached to 5 μmol· L- 1 and the relative standard deviation （RSD） was 3.0% fornicotinamide. The average spiked recovery was 99. 1%. This device has realized miniaturization andintegration with high sensitivity, good selectivity and low cost, and could be used for the quality con-trol of medicines.