Department of Ophthalmology, University of Miami-Bascom Palmer Eye Institute, Miami, FL 33136, USA; E-Mails:
Department of Structural Biology, Stanford University, Palo Alto, CA 94305, USA; E-Mail:
Biosensors (Basel). 2013 Feb 6;3(1):77-88. doi: 10.3390/bios3010077. eCollection 2013 Mar.
A nanoplasmonic biosensor for highly-sensitive, single-step detection of protein biomarkers is presented. The principle is based on the utilization of the optical scattering properties of gold nanorods (GNRs) conjugated to bio-recognition molecules. The nanoplasmonic properties of the GNRs were utilized to detect proteins using near-infrared light interferometry. We show that the antibody-conjugated GNRs can specifically bind to our model analyte, Glucose Transporter-1 (Glut-1). The signal intensity of back-scattered light from the GNRs bound after incubation, correlated well to the Glut-1 concentration as per the calibration curve. The detection range using this nanoplasmonic immunoassay ranges from 10 ng/mL to 1 ug/mL for Glut-1. The minimal detectable concentration based on the lowest discernable concentration from zero is 10 ng/mL. This nanoplasmonic immunoassay can act as a simple, selective, sensitive strategy for effective disease diagnosis. It offers advantages such as wide detection range, increased speed of analysis (due to fewer incubation/washing steps), and no label development as compared to traditional immunoassay techniques. Our future goal is to incorporate this detection strategy onto a microfluidic platform to be used as a point-of-care diagnostic tool.
一种用于高度敏感、单步检测蛋白质生物标志物的纳米等离子体生物传感器被提出。其原理基于利用与生物识别分子偶联的金纳米棒（GNRs）的光学散射特性。GNRs 的纳米等离子体特性被用于使用近红外光干涉法检测蛋白质。我们表明，抗体偶联的 GNRs 可以特异性地与我们的模型分析物葡萄糖转运蛋白-1（Glut-1）结合。孵育后结合的 GNRs 的背散射光的信号强度与 Glut-1 浓度根据校准曲线很好地相关。使用这种纳米等离子体免疫分析的检测范围对于 Glut-1 为 10ng/mL 至 1ug/mL。基于零的最低可分辨浓度的最小可检测浓度为 10ng/mL。这种纳米等离子体免疫分析可以作为一种简单、选择性、灵敏的策略，用于有效的疾病诊断。与传统的免疫分析技术相比，它具有广泛的检测范围、更快的分析速度（由于孵育/洗涤步骤更少）和无需标记开发等优点。我们的未来目标是将这种检测策略整合到微流控平台上，用作即时诊断工具。
