利用纸基微芯片便捷、直观的优势,采用吩嗪二甲酯硫酸盐(PMS)/氯化硝基四氮唑蓝(NBT)显色体系,借助凝胶成像仪和普通照相机两种成像方式,建立了纸基微孔阵列芯片比色法检测乳酸脱氢酶(LDH)的方法。在最佳实验条件下,显色强度与LDH浓度呈线性相关。采用凝胶成像仪检测时,线性范围为10~150 U/L,检出限(3σ)为9.44 U/L(n=18)。采用照相法获得的线性范围为15~150 U/L,检出限(3σ)为12.36 U/L(n=18)。实验表明,人血清白蛋白(HSA)对显色结果具有增强作用,探讨了HSA的增色作用,并以HSA为增强试剂得到工作曲线。基于纸基微孔阵列芯片的LDH活性测定方法具有操作简单、结果直观可见、灵敏度高等优点,对于脱氢酶类的便捷检测有一定参考价值,可望在生物医疗检测领域获得应用。
A low-cost, simple, sensitive detection method of lactate dehydrogense (LDH) was developed on paper-based microwell arrays microfluidic device. The phenazine methyl sulfate/nitrotetrazolium blue chloride (PMS/NBT) detection system was used for LDH detection and the colorimetric results were recorded by both Gel Documentation System and a common camera. Under the optimized conditions, the colorimetric intensity showed a linear correlation to the activity of LDH in the range of 10 to 150 U/L with a limit of detection (LOD) of 9.44 U/L (30σ) by Gel Documentation System; and the linear range was 15-150 U/L by camera with a LOD of 12.36 U/L (30σ). Foremost, it was found that human serum albumin (HSA) had an effect on the colorimetric enhancement in this detection system. This low-cost, portable paper-based analytical platform could be suitable for the application in the point-of-care with high sensitivity and reproducibility.