Jung Jaeyeon, Na Kyunga, Lee Jonghwan, Kim Ki-Woo, Hyun Jinho
Department of Biosystems and Biomaterials Science and Engineering, Seoul National University, Seoul 151-742, Republic of Korea.
Anal Chim Acta. 2009 Sep 28;651(1):91-7. doi: 10.1016/j.aca.2009.07.057. Epub 2009 Jul 29.
This paper introduces strategies for enhancement of a surface plasmon resonance (SPR) signal by adopting colloidal gold nanoparticles (AuNPs) and a SiO(2) layer on a gold surface. AuNPs on SiO(2) on a gold surface were compared with an unmodified gold surface and a SiO(2) layer on a gold surface with no AuNPs attached. The modified surfaces showed significant changes in SPR signal when biomolecules were attached to the surface as compared with an unmodified gold surface. The detection limit of AuNPs immobilized on a SPR chip was 0.1 ng mL(-1) for the prostate-specific antigen (PSA), a cancer marker, as measured with a spectrophotometer. Considering that the conventional ELISA method can detect approximately 10 ng mL(-1) of PSA, the strategy described here is much more sensitive (approximately 100 fold). The enhanced shift of the absorption curve resulted from the coupling of the surface and particle plasmons by the SiO(2) layer and the AuNPs on the gold surface.
本文介绍了通过在金表面采用胶体金纳米颗粒（AuNPs）和SiO₂层来增强表面等离子体共振（SPR）信号的策略。将金表面SiO₂上的AuNPs与未修饰的金表面以及金表面上未附着AuNPs的SiO₂层进行了比较。当生物分子附着在表面时，与未修饰的金表面相比，修饰后的表面在SPR信号上显示出显著变化。用分光光度计测量，固定在SPR芯片上的AuNPs对癌症标志物前列腺特异性抗原（PSA）的检测限为0.1 ng mL⁻¹。考虑到传统酶联免疫吸附测定（ELISA）方法可检测约10 ng mL⁻¹的PSA，这里描述的策略要灵敏得多（约100倍）。吸收曲线的增强位移是由SiO₂层和金表面上的AuNPs使表面等离子体与粒子等离子体耦合所致。
