Hatch A, Kamholz A E, Hawkins K R, Munson M S, Schilling E A, Weigl B H, Yager P
Department of Bioengineering, Box 352141, University of Washington, Seattle, WA 98195, USA.
Nat Biotechnol. 2001 May;19(5):461-5. doi: 10.1038/88135.
We have developed a rapid diffusion immunoassay that allows measurement of small molecules down to subnanomolar concentrations in <1 min. This competitive assay is based on measuring the distribution of a labeled probe molecule after it diffuses for a short time from one region into another region containing antigen-specific antibodies. The assay was demonstrated in the T-sensor, a simple microfluidic device that places two fluid streams in contact and allows interdiffusion of their components. The model analyte was phenytoin, a typical small drug molecule. Clinically relevant levels were measured in blood diluted from 10- to 400-fold in buffer containing the labeled antigen. Removal of cells from blood samples was not necessary. This assay compared favorably with fluorescence polarization immunoassay (FPIA) measurements. Numerical simulations agree well with experimental results and provide insight for predicting assay performance and limitations. The assay is homogeneous, requires <1 microl of reagents and sample, and is applicable to a wide range of analytes.
我们开发了一种快速扩散免疫测定法，可在不到1分钟的时间内测量低至亚纳摩尔浓度的小分子。这种竞争性测定法基于测量标记探针分子在短时间内从一个区域扩散到另一个含有抗原特异性抗体的区域后的分布情况。该测定法在T传感器中得到了验证，T传感器是一种简单的微流控装置，可使两种流体流接触并允许其成分相互扩散。模型分析物是苯妥英，一种典型的小药物分子。在含有标记抗原的缓冲液中，对稀释10至400倍的血液中的临床相关水平进行了测量。无需从血样中去除细胞。该测定法与荧光偏振免疫测定法（FPIA）测量结果相比具有优势。数值模拟与实验结果吻合良好，并为预测测定性能和局限性提供了见解。该测定法是均相的，需要不到1微升的试剂和样品，并且适用于多种分析物。
