title: Peptidic β-sheet binding with Congo Red allows both reduction of error variance and signal amplification for immunoassays.
abstract: Although conventional enzyme-linked immunosorbent assays (ELISA) and related assays have been widely applied for the diagnosis of diseases, many of them suffer from large error variance for monitoring the concentration of targets over time, and insufficient limit of detection (LOD) for assaying dilute targets. We herein report a readout mode of ELISA based on the binding between peptidic β-sheet structure and Congo Red. The formation of peptidic β-sheet structure is triggered by alkaline phosphatase (ALP). For the detection of P-Selectin which is a crucial indicator for evaluating thrombus diseases in clinic, the 'β-sheet and Congo Red' mode significantly decreases both the error variance and the LOD (from 9.7ng/ml to 1.1 ng/ml) of detection, compared with commercial ELISA (an existing gold-standard method for detecting P-Selectin in clinic). Considering the wide range of ALP-based antibodies for immunoassays, such novel method could be applicable to the analysis of many types of targets.
authors.affiliation: Clinical Laboratory of South Building, Chinese P. L. A. General Hospital, No. 28 Fuxing Road, Beijing 100853, China; Beijing Engineering Research Center for BioNanotechnology and CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience, National Center for NanoScience and Technology and The University of Chinese Academy of Sciences, No. 11 Zhongguancun Beiyitiao, Beijing 100190, China.
authors.forename: Yunyun
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Beijing Engineering Research Center for BioNanotechnology and CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience, National Center for NanoScience and Technology and The University of Chinese Academy of Sciences, No. 11 Zhongguancun Beiyitiao, Beijing 100190, China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Clinical Laboratory of South Building, Chinese P. L. A. General Hospital, No. 28 Fuxing Road, Beijing 100853, China.
authors.forename: Xinli
authors.initials: X
authors.lastname: Deng
authors.affiliation: Clinical Laboratory of South Building, Chinese P. L. A. General Hospital, No. 28 Fuxing Road, Beijing 100853, China. Electronic address: yulongc@263.net.
authors.forename: Yulong
authors.initials: Y
authors.lastname: Cong
authors.affiliation: Beijing Engineering Research Center for BioNanotechnology and CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience, National Center for NanoScience and Technology and The University of Chinese Academy of Sciences, No. 11 Zhongguancun Beiyitiao, Beijing 100190, China. Electronic address: xingyujiang@nanoctr.cn.
authors.forename: Xingyu
authors.initials: X
authors.lastname: Jiang
mesh_terms: D000469:Alkaline Phosphatase; D015415:Biomarkers / Q000097:blood; D003124:Colorimetry / Q000295:instrumentation; D003224:Congo Red / Q000737:chemistry*; D004797:Enzyme-Linked Immunosorbent Assay / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D019007:P-Selectin / Q000097:blood*; D010455:Peptides / Q000737:chemistry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013927:Thrombosis / Q000097:blood* / Q000175:diagnosis*
chemical_list: D015415:Biomarkers; D019007:P-Selectin; D010455:Peptides; D003224:Congo Red; D000469:Alkaline Phosphatase
keywords: Congo red; Immunoassays; P-Selectin; Peptidic β-sheet; Readout mode