High sensitive detection of C-reactive protein by total internal reflection fluorescence microscopy on rapidly making nanoarray protein chip

This study investigated a method for the high sensitivity detection and quantification of the C-reactive protein (CRP) in human serum using total internal reflection fluorescence microscopy (TIRFM) on a rapidly made nanoarray protein chip The nanoarray biotin-probe was patterned onto 3-mercaptopropyl trimethoxysilane-coated cover glass with a spot diameter of similar to 400 nm within 1 min using a NanoeNablei (TM)-based surface patterning tool The unlabeled CRP molecules were detected in human sera using TIRFM, based on a sandwich fluorescence immunoassay. The linear regression for standard CRP in the range of 50 zM-1 fM was determined using the equation y = 0 437x + 84 991 (R = 0.9993) This proposed method was similar to 2000 times faster than conventional atomic force microscopy based clip-pen nanolithography in terms of the chip manufacturing process Additionally this method was 6 x 10(6) times more sensitive than enzyme-linked immunosorbent assay and exhibited a wide dynamic linear range (50 zM-1 fM) (C) 2010 Elsevier B V All rights reserved