适体
检出限
分析物
材料科学
表面等离子共振
生物传感器
瑞利散射
胶体金
免疫金标记
等离子体子
溶菌酶
纳米技术
纳米颗粒
分析化学(期刊)
化学
光电子学
光学
色谱法
物理
电子显微镜
生物
生物化学
遗传学
作者
Phuoc Long Truong,Seung Phill Choi,Sang Jun Sim
出处
期刊:Small
[Wiley]
日期:2013-04-19
卷期号:9 (20): 3485-3492
被引量:24
标识
DOI:10.1002/smll.201202638
摘要
A strategy for attomolar-level detection of small molecule-size proteins is reported based on Rayleigh light scattering spectroscopy of individual nanoplasmonic aptasensors by exploiting the outstanding characteristics of gold colloids to amplify the nontransparent resonant signal at ultralow analyte concentrations. The fabrication method utilizes thiol-mediated adsorption of a DNA aptamer on the immobilized Au nanoparticle surface, the interfacial binding characteristics of the aptamer with its target molecules, and the antibody-antigen interaction through plasmonic resonance coupling of the Au nanoparticles. Using lysozyme as a model analyte for disease detection, the detection limit of the aptasensor is ∼7 × 10(3) aM, corresponding to the LSPR λmax shift of ∼2.25 nm. Up to a 380% increase in the localized resonant λmax shift is demonstrated upon antibody binding to the analyte compared to the primary response during signal amplification using immunogold colloids. This enhancement leads to a limit of detection of ∼7 aM, which is an improvement of three orders of magnitude. The results demonstrate substantial promise for developing coupled plasmonic nanostructures for ultrasensitive detection of various biological and chemical analytes.
科研通智能强力驱动
Strongly Powered by AbleSci AI