Department of Food Science, College of Agriculture and Life Sciences, Cornell University, Ithaca 14853, NY, USA.
Lab Chip. 2019 Oct 9;19(20):3448-3460. doi: 10.1039/c9lc00734b.
Point-of-care (POC) diagnostics have shown excellent potential in rapid biological analysis and health/disease monitoring. Here, we introduce a versatile, cost-effective, flexible, and wearable POC biomarker patch for effective sweat collection and health monitoring. We design and fabricate channels/patterns on filter paper using wax printing technology, which can direct sweat to collection and biomarker detection zones on the proposed platform. The detection zones are designed to measure the amount of collected sweat, in addition to measuring the sweat pH, and glucose (a potential diabetic biomarker), and lactate concentrations. It is significantly challenging to measure glucose in human sweat by colorimetric methods due to the extremely low glucose levels found in this medium. However, we overcame this issue by effectively engineering our wearable biosensor for optimal intake, storage, and evaporation of sweat. Our design concentrates the colorant (indicator) into a small detection zone and significantly increases the sensitivity for the sweat glucose sensing reactions. The device can thus detect glucose in physiological glucose concentration range of 50-300 μM. This cost-effective and wearable biosensor can provide instant in situ quantitative results for targets of interest, such as glucose, pH, and lactate, when coupled with the imaging and computing functionalities of smartphones. Meanwhile, it is also feasible to extract the air-dried sweat from the storage zone for further ex situ measurements of a broader portfolio of biomarkers, leading to applications of our wearable biosensor in personalized nutrition and medicine.
即时检测（POC）在快速生物分析和健康/疾病监测方面显示出了巨大的潜力。在这里，我们介绍了一种多功能、经济高效、灵活和可穿戴的 POC 生物标志物贴片，用于有效收集汗液和进行健康监测。我们使用蜡印技术在滤纸上设计和制作通道/图案，这些通道/图案可以将汗液引导至收集区和平台上的生物标志物检测区。这些检测区不仅可以测量收集的汗液量，还可以测量汗液的 pH 值、葡萄糖（一种潜在的糖尿病生物标志物）和乳酸浓度。由于人体汗液中葡萄糖含量极低，通过比色法测量葡萄糖极具挑战性。然而，我们通过对可穿戴生物传感器进行有效设计，实现了最佳的汗液摄入、储存和蒸发，克服了这一问题。我们的设计将显色剂（指示剂）集中在一个小的检测区内，从而显著提高了对汗液葡萄糖传感反应的灵敏度。因此，该设备可以检测 50-300μM 生理葡萄糖浓度范围内的葡萄糖。当与智能手机的成像和计算功能相结合时，这种经济高效且可穿戴的生物传感器可以为葡萄糖、pH 值和乳酸等目标提供即时的原位定量结果。同时，也可以从存储区中提取干燥的汗液进行更广泛的生物标志物的离体测量，从而将可穿戴生物传感器应用于个性化营养和医学领域。
