Application of Photonic Crystal Enhanced Fluorescence to Cancer Biomarker Microarrays

摘要

ABSTRACT: We report on the use of photonic crystal surfaces as a high-sensitivitynplatform for detection of a panel of cancer biomarkers in a protein microarraynformat. The photonic crystal surface is designed to provide an optical resonance atnthe excitation wavelength of cyanine-5 (Cy5), thus providing an increase innfluorescent intensity for Cy5-labeled analytes measured with a confocal micro-narray scanner, compared to a glass surface. The sandwich enzyme-linked immuno-nsorbent assay (ELISA) is undertaken on a microarray platform to undertake ansimultaneous, multiplex analysis of 24 antigens on a single chip. Our results shownthat the resonant excitation effect increases the signal-to-noise ratio by 3.8- to 6.6-fold, resulting in a decrease in detection limits ofn6-89%, with the exact enhancement dependent upon the antibody-antigen interaction. Dose-response characterization of thenphotonic crystal antibody microarrays shows the capability to detect common cancer biomarkers in the <2 pg/mL concentrationnrange within a mixed sample.