摘要
报道了基于金纳米棒表面增强拉曼散射(SERS)的免疫检测.将拉曼活性分子对巯基苯甲酸吸附于金纳米棒表面,制备出SERS标记的金纳米棒探针.该探针和蛋白抗体结合形成SERS标记抗体.通过SERS标记抗体、待测抗原和俘获抗体(固体基底上修饰的抗体,即俘获抗体)之间的免疫应答反应,将金纳米棒探针组装到固体基底上,形成SERS标记抗体-抗原-俘获抗体"三明治"夹心复合体.待测抗原浓度越大,固体基底上俘获的金纳米棒探针的数目越多,从而可通过SERS信号的强弱来检测待测抗原的浓度.由于金纳米棒的表面等离子体共振(SPR)峰位置可以在较宽的范围内调控,可通过激发光和SPR的耦合来提高SERS信号,从而提高免疫检测的灵敏度.单组分抗原可检出的浓度范围高于1×10-8mg/mL.
An immunoassay detection based on surface-enhanced Raman scattering （SERS） from gold nanorods （NRs） was studied. Raman active molecule 4-mercaptobenzoic acid was adsorbed on gold NRs, forming SERS-tagged gold nanoprobes. Upon adsorption of antibody to the nanoprobes, the antibody was tagged by SERS. Through the immunoassay reactions among the SERS-tagged antibody, detected antigen, and antibody supported on solid substrate （capture antibody）, SERS-tagged antibody-antigen-capture antibody sandwich conjugates were formed on the solid substrate. The higher the concentration of the detected antigen is, the larger the number of the gold nanoprobes on the solid substrate is. Therefore, SERS intensity signals the concentration of the detected antigen. Because the position of surface plasmon resonance （SPR） of the gold NRs can be tuned in a wide range, one can couple the SPR and the excitation line to maximize the SERS signals and thus the immunoassay sensitivity. The detected concentration for a single antigen component is higher than 1× 10^-8 mgomL^-1.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
2009年第14期1603-1608,共6页
Acta Chimica Sinica
基金
国家自然科学基金(Nos.20603008
20873037)
湖南省自然科学基金(No.06JJ3006)资助项目
