微流控纸芯片的开发用于尿液总蛋白含量的快速检测

Development of the paper-based microfluidic device for rapid detection of total protein analysis in urine

文章采用紫外光刻技术制作微流控纸芯片,并将其开发用于尿液中总蛋白含量的快速检测。确定了纸芯片上溴酚蓝指示剂(溴酚蓝)的加载量为0.2μL,浓度为10 mg/mL。采用蘸取和滴加两种加样方法,确定加样量为10μL。并选择0.9%NaCl缓冲液作为空白或用以稀释蛋白质标准品。整个检测过程在5 min完成,并且肉眼可见。通过量化由显微镜CCD拍摄的芯片图像的灰度来执行半定量,检测限为0.21 mg/d L,定量限为0.69 mg/d L。对模拟尿液中总蛋白质含量分析,得到回收率为96.7%~103.82%。并且在3个月内评估纸芯片测定法有良好的稳定性和可重复性,表明该测定潜在地可以在完整的生物样品中进行。我们所构建的微流控纸芯片可以实现对正常尿液和蛋白质超标尿液的检测,有望用于临床边检测中肾病的早期检测。

In t his p aper,we r eporte a p aper-based r apid detection a ssay for t otal p rotein a nalysis i n u rine.T he p arameters i ncluding selection of working buffer,sample loading method and amount,probe loading amount and probe concentration were optimized.The probe amount is 0.2μL for each detection test and the sample amount is 10μL.Dipping and dropwise addition are developed for sample loading,both of which could be used to wick the sample to the detection zone.The detection process could be performed with the visualized color change within 5 min.Semi-quantification could be performed by quantifying the greysacle of the chip image captured by microscope or cell phone.The limit of detection is 0.21 mg/dL and the limit of quantification is 0.69 mg/dL.Urea in the urine sample would not interfere in the result for the total protein analysis in urine using the paper-based microfluidics.Total protein analysis in the simulated urine is performed and the recovery rate is 96.78%to 103.82%.The good stability and reproducibility of the paper-based assay evaluated within three months indicated that the assay could be potentially performed in the complete biological samples.