State Key Laboratory of Precision Measuring Technology & Instruments, College of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin 300072, China.
State Key Laboratory of Precision Measuring Technology & Instruments, College of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin 300072, China.
Anal Chim Acta. 2017 Apr 29;964:170-177. doi: 10.1016/j.aca.2017.01.051. Epub 2017 Jan 31.
This paper reports a surface functionalization strategy for protein detections based on biotin-derivatized poly(l-lysine)-grafted oligo-ethylene glycol (PLL-g-OEG-Biotin) copolymers. Such strategy can be used to attach the biomolecule receptors in a reproducible way simply by incubation of the transducer element in a solution containing such copolymers which largely facilitated the sensor functionalization at an industrial scale. As the synthesized copolymers are cationic in physiology pH, surface biotinylation can be easily achieved via electrostatic adsorption on negatively charged sensor surface. Biotinylated receptors can be subsequently attached through well-defined biotin-streptavidin interaction. In this work, the bioactive sensor surfaces were applied for mouse IgG and prostate specific antigen (PSA) detections using quartz crystal microbalance (QCM), optical sensor (BioLayer Interferometry) and conventional ELISA test (colorimetry). A limit of detection (LOD) of 0.5 nM was achieved for PSA detections both in HEPES buffer and serum dilutions in ELISA tests. The synthesized PLL-g-OEG-Biotin copolymers with different OEG chain length were also compared for their biosensing performance. Moreover, the surface regeneration was achieved by pH stimulation to remove the copolymers and the bonded analytes, while maintaining the sensor reusability as well. Thus, the developed PLL-g-OEG-Biotin surface assembling strategy is believed to be a versatile surface coating method for protein detections with multi-sensor compatibility.
本文报道了一种基于生物素衍生的聚（L-赖氨酸）接枝聚乙二醇（PLL-g-OEG-Biotin）共聚物的蛋白质检测表面功能化策略。这种策略可以通过将换能器元件在含有这种共聚物的溶液中孵育，以可重复的方式将生物分子受体附着在表面上，这在工业规模上极大地促进了传感器的功能化。由于合成的共聚物在生理 pH 值下呈阳离子性，因此可以通过静电吸附在带负电荷的传感器表面上轻松实现表面生物素化。随后可以通过明确的生物素-链霉亲和素相互作用将生物素化的受体附着在表面上。在这项工作中，生物活性传感器表面被应用于使用石英晶体微天平（QCM）、光学传感器（生物层干涉测量法）和常规 ELISA 测试（比色法）进行小鼠 IgG 和前列腺特异性抗原（PSA）的检测。在 ELISA 测试中，在 HEPES 缓冲液和血清稀释液中，PSA 检测的检测限（LOD）达到了 0.5 nM。还比较了具有不同 OEG 链长的合成 PLL-g-OEG-Biotin 共聚物的生物传感性能。此外，通过 pH 刺激实现了表面再生，以去除共聚物和结合的分析物，同时保持传感器的可重复使用性。因此，所开发的 PLL-g-OEG-Biotin 表面组装策略被认为是一种用于蛋白质检测的多功能表面涂层方法，具有多传感器兼容性。
