Chemical Engineering, ‡Media Arts and Sciences, Media Lab, and §Program in Polymers and Soft Matter, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
ACS Sens. 2017 Nov 22;2(11):1589-1593. doi: 10.1021/acssensors.7b00745. Epub 2017 Nov 13.
We report methods for stabilizing cellulose-based immunoassays and using this platform to analyze human saliva. Stabilization treatments of immunoassays for matrix metalloproteinases (MMP)-8 and -9, biomarkers of periodontal disease, were conducted and compared, revealing that anti-MMP-8 and -9 capture antibodies could be stabilized with the addition of a 5% trehalose solution to the test zones, followed by drying in a vacuum oven. After stabilization, the paper devices retained equivalent binding activity to that of freshly prepared tests for 14 days-a time frame that enables US-based clinical testing of this diagnostic assay. A saliva pretreatment method was developed to remove viscous elements without reducing the concentration or binding activity of dissolved proteins. Immunoassays were stored in ziplock bags containing desiccant, and used to detect nanomolar concentrations of MMP-9 in human saliva across the relevant clinical concentration range. These methods and findings facilitate rapid, affordable validation studies of this and other biomarkers that are found in saliva using vertical flow immunoassays.
我们报告了稳定基于纤维素的免疫分析的方法，并利用该平台分析了人类唾液。对基质金属蛋白酶（MMP）-8 和 -9 的免疫分析进行了稳定处理，这是牙周病的生物标志物，并进行了比较，结果表明，添加 5%海藻糖溶液到测试区，然后在真空烤箱中干燥，可以稳定抗 MMP-8 和 -9 捕获抗体。稳定后，纸装置在 14 天内保留与新制备测试相当的结合活性-这一时间框架使这种诊断测定在美国进行临床测试成为可能。开发了一种唾液预处理方法，可在不降低溶解蛋白浓度或结合活性的情况下去除粘性成分。免疫分析储存在含有干燥剂的拉链袋中，并用于检测人类唾液中 MMP-9 的纳摩尔浓度，横跨相关的临床浓度范围。这些方法和发现促进了使用垂直流动免疫分析对这种和其他在唾液中发现的生物标志物进行快速、经济实惠的验证研究。
