Burenin Alexandr G, Urusov Alexandr E, Betin Alexei V, Orlov Alexey V, Nikitin Maxim P, Ksenevich Tatiana I, Gorshkov Boris G, Zherdev Anatoly V, Dzantiev Boris B, Nikitin Petr I
Prokhorov General Physics Institute, Russian Academy of Sciences, 38 Vavilov Str., 119991, Moscow, Russia.
Anal Bioanal Chem. 2015 May;407(14):3955-64. doi: 10.1007/s00216-015-8600-y. Epub 2015 Mar 11.
A 3-channel biosensor based on spectral correlation interferometry (SCI) has been adapted for direct optical detection of antigens by measuring changes in thickness of a biolayer on functionalized glass slips employed as affordable single-use sensor chips. The instrument is insensitive to the bulk refractive index of a solution under test and provides signals in metrological units (pm or nm). Using real-time monitoring with the SCI, protocols for fabrication of sensor chips with different functional (epoxylated, carboxylated, and biotinylated) surfaces for antibody immobilization have been developed and optimized to minimize chip-to-chip variations and achieve better limit of detection (LOD), shorter assay time, and longer shelf life. The optimized coupling surfaces have been compared for detection of human serum albumin (HSA) used as a model agent of medical significance. The dynamic ranges for measuring the HSA concentration were 0.07-20, 0.12-30, and 0.25-10 μg/ml, and the assay durations were less than 20, 15, and 30 min for the epoxylated, carboxylated, and biotinylated chips, respectively. The advantages of each type of sensor chip have been shown, namely, the carboxylated chips feature the shortest assay time, the epoxylated ones demonstrate the best LOD, and the biotinylated chips exhibit the longest shelf life in an unprotected environment. The developed protocols of antibody immobilization can be used in different biosensors and assay techniques including those based on fluorescent, magnetic or plasmonic labels, etc. The SCI is well compatible with various partially transparent layers used in biosensing and with microarrays for multi-analyte detection.
一种基于光谱相关干涉测量法（SCI）的三通道生物传感器，已通过测量用作经济实惠的一次性传感器芯片的功能化载玻片上生物层厚度的变化，被适配用于抗原直接光学检测。该仪器对被测溶液的体折射率不敏感，并以计量单位（皮米或纳米）提供信号。利用SCI进行实时监测，已开发并优化了用于固定抗体的具有不同功能（环氧基化、羧基化和生物素化）表面的传感器芯片制造方案，以最小化芯片间差异，并实现更好的检测限（LOD）、更短的检测时间和更长的保质期。已比较了优化后的偶联表面对用作具有医学意义的模型试剂的人血清白蛋白（HSA）的检测情况。环氧基化、羧基化和生物素化芯片测量HSA浓度的动态范围分别为0.07 - 20、0.12 - 30和0.25 - 10μg/ml，检测持续时间分别小于20、15和30分钟。已展示了每种类型传感器芯片的优势，即羧基化芯片检测时间最短，环氧基化芯片检测限最佳，生物素化芯片在未受保护环境下保质期最长。所开发的抗体固定方案可用于不同的生物传感器和检测技术，包括基于荧光、磁性或等离子体标记等的技术。SCI与生物传感中使用的各种部分透明层以及用于多分析物检测的微阵列具有良好的兼容性。
