Multiplexed Cancer Biomarker Detection Using Quartz-Based Photonic Crystal Surfaces

详细信息    查看全文

• 作者：Cheng-Sheng Huang ; Vikram Chaudhery ; Anusha Pokhriyal ; Sherine George ; James Polans ; Meng Lu ; Ruimin Tan ; Richard C. Zangar ; Brian T. Cunningham
• 刊名：Analytical Chemistry
• 出版年：2012
• 出版时间：January 17, 2012
• 年：2012
• 卷：84
• 期：2
• 页码：1126-1133
• 全文大小：392K
• 年卷期：v.84,no.2(January 17, 2012)
• ISSN：1520-6882

文摘

A photonic crystal (PC) surface is demonstrated as a high-sensitivity platform for detection of a panel of 21 cancer biomarker antigens using a sandwich enzyme-linked immunosorbent assay (ELISA) microarray format. A quartz-based PC structure fabricated by nanoimprint lithography, selected for its low autofluorescence, supports two independent optical resonances that simultaneously enable enhancement of fluorescence detection of biomarkers and label-free quantification of the density of antibody capture spots. A detection instrument is demonstrated that supports fluorescence and label-free imaging modalities, with the ability to optimize the fluorescence enhancement factor on a pixel-by-pixel basis throughout the microarray using an angle-scanning approach for the excitation laser that automatically compensates for variability in surface chemistry density and capture spot density. Measurements show that the angle-scanning illumination approach reduces the coefficient of variation of replicate assays by 20鈥?9% compared to ordinary fluorescence microscopy, thus supporting reduction in limits of detectable biomarker concentration. Using the PC resonance, biomarkers in mixed samples were detectable at the lowest concentrations tested (2.1鈥?1 pg/mL), resulting in a three-log range of quantitative detection.