College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, PR China.
Anal Chim Acta. 2013 Mar 26;769:114-20. doi: 10.1016/j.aca.2013.01.034. Epub 2013 Jan 25.
This paper reports the utilization of triangular silver nanoplates (TSNPs) to enhance the sensitivity of surface plasmon resonance (SPR) biosensor. TSNPs modified with 3-mercaptopropinic acid (MPA) were simply mixed with chitosan and glutaraldehyde to form TSNPs/chitosan composite. The composite was deposited on Au film as immobilization substrate for SPR biosensor. The novel structures of TSNPs are preserved against etching by MPA and chitosan polymer. Moreover, chitosan cross-linked by glutaraldehyde enables antibody to be immobilized on fabricated substrate directly via Schiff alkali reaction. In the optimized conditions, the resulting biosensor based on TSNPs/chitosan composite shows a satisfactory response to bovine IgG in the concentration range of 0.075-40.00 μg mL(-1). While the biosensor based on chitosan without TSNPs shows a response in the concentration range of 0.6-40 μg mL(-1) and the biosensor based on Au film shows a response in the concentration range of 2.5-40 μg mL(-1). The experiment results show that the sensitivity of SPR biosensor based on TSNPs/chitosan composite was significantly enhanced and the immobilization procedure of antibody was simplified.
本文报道了利用三角形银纳米片（TSNPs）来提高表面等离子体共振（SPR）生物传感器的灵敏度。用巯基丙酸（MPA）修饰的 TSNPs 与壳聚糖和戊二醛简单混合，形成 TSNPs/壳聚糖复合材料。该复合材料被沉积在 Au 膜上作为 SPR 生物传感器的固定化基底。MPA 和壳聚糖聚合物对 TSNPs 的结构起到了保护作用，防止其被蚀刻。此外，壳聚糖通过戊二醛交联，使得抗体可以直接通过希夫碱反应固定在制备的基底上。在优化条件下，基于 TSNPs/壳聚糖复合材料的生物传感器对牛 IgG 在 0.075-40.00 μg mL(-1) 的浓度范围内表现出令人满意的响应。而基于没有 TSNPs 的壳聚糖的生物传感器在 0.6-40 μg mL(-1) 的浓度范围内有响应，基于 Au 膜的生物传感器在 2.5-40 μg mL(-1) 的浓度范围内有响应。实验结果表明，基于 TSNPs/壳聚糖复合材料的 SPR 生物传感器的灵敏度显著提高，并且简化了抗体的固定化过程。
