title: Molecular switching fluorescence based high sensitive detection of label-free C-reactive protein on biochip.
abstract: A novel detection technique on biochip for the quantification of label-free C-reactive protein (CRP) based on molecular switching of fluorescence (MSF) is demonstrated by total internal reflection fluorescence microscopy. It alters fluorescence intensity of fluoreseinamine isomer 1 (FAI) upon binding with its specific ligand, O-phosphorylethanolamine (PEA). In the MSF-based detection, FAI was used as an ink, printed on a 3-glycidoxypropyl-trimethoxysilane (GPTS)-coated glass coverslip. With the addition of GPTS conjugated PEA solution to the FAI-printed coverslip, the fluorescence intensity was remarkably decreased. Addition of CRP increased fluorescence intensity linearly in the range of 800 aM to 500 fM (R=0.997). The MSF-based biochip assay for the estimation of CRP in human sera showed ∼200 times increased detection sensitivity in less than a third of the time to obtain results using a conventional enzyme-linked immunosorbent assay. This biochip detection is a promising new technique for the quantification of CRP molecules from trace amounts of clinical samples.
authors.affiliation: Department of Chemistry, Chonbuk National University, Jeonju 561-756, South Korea.
authors.forename: Md Shahinul
authors.initials: MS
authors.lastname: Islam
authors.forename: Hyunung
authors.initials: H
authors.lastname: Yu
authors.forename: Hee Gu
authors.initials: HG
authors.lastname: Lee
authors.forename: Seong Ho
authors.initials: SH
authors.lastname: Kang
mesh_terms: D001774:Blood Chemical Analysis / Q000379:methods / Q000706:statistics & numerical data; D002097:C-Reactive Protein / Q000032:analysis*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000706:statistics & numerical data; D019793:Fluorescein; D005456:Fluorescent Dyes; D006801:Humans; D018625:Microscopy, Atomic Force; D008856:Microscopy, Fluorescence / Q000379:methods; D040081:Protein Array Analysis / Q000379:methods* / Q000706:statistics & numerical data; D012680:Sensitivity and Specificity; D012821:Silanes
chemical_list: C403136:3-glycidoxypropyltrimethoxysilane; D005456:Fluorescent Dyes; D012821:Silanes; D002097:C-Reactive Protein; D019793:Fluorescein