title: High sensitive detection method for protein by combining the magnetic separation with cation exchange based signal amplification.
abstract: PSA is a member of low abundance proteins and serves as a critical indicator of the development and therapy efficacy for prostate cancer. In this study, a facile and high sensitive method was developed for serum PSA detection by integrating the immunomagnetic separation and cation exchange based signal amplification. On the basis of nanoparticle preparation and immunoprobe construction, PSA in serum was captured, separated by the immunomagnetic probe and then interacted with the quantum dots (QDs) based immunofluorescence probe; Zn2+inside QDs was replaced by Ag+within seconds, after which fluorescence signal was amplified by Fluozin-3, the Zn2+responsive dye. Under optimized conditions, low detection limit (1.56pg/mL), wide linear range (1.56-25ng/mL) and good repeatability (intra-coefficient variation=3.18%) were achieved, which is superior to commercialized ELISA kit. These results demonstrated the potential of our high sensitive method for PSA detection in clinical.
authors.affiliation: School of Life Science, Beijing Institute of Technology, Beijing 100081, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Xu
authors.affiliation: School of Life Science, Beijing Institute of Technology, Beijing 100081, China.
authors.forename: Qian-Mei
authors.initials: QM
authors.lastname: Zhang
authors.affiliation: School of Life Science, Beijing Institute of Technology, Beijing 100081, China.
authors.forename: Dong-Xu
authors.initials: DX
authors.lastname: Zhao
authors.affiliation: School of Life Science, Beijing Institute of Technology, Beijing 100081, China.
authors.forename: Ya-Ru
authors.initials: YR
authors.lastname: Liu
authors.affiliation: School of Life Science, Beijing Institute of Technology, Beijing 100081, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Chen
authors.affiliation: School of Life Science, Beijing Institute of Technology, Beijing 100081, China.
authors.forename: Gui-Hong
authors.initials: GH
authors.lastname: Lu
authors.affiliation: School of Life Science, Beijing Institute of Technology, Beijing 100081, China. Electronic address: hyanxie@bit.edu.cn.
authors.forename: Hai-Yan
authors.initials: HY
authors.lastname: Xie
mesh_terms: D002412:Cations / Q000737:chemistry*; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000737:chemistry; D006801:Humans; D018189:Immunomagnetic Separation / Q000379:methods*; D007610:Kallikreins / Q000032:analysis* / Q000302:isolation & purification*; D057230:Limit of Detection; D060526:Magnetic Fields; D053758:Nanoparticles / Q000737:chemistry*; D017430:Prostate-Specific Antigen / Q000032:analysis* / Q000302:isolation & purification*; D045663:Quantum Dots; D013050:Spectrometry, Fluorescence
chemical_list: D002412:Cations; D005456:Fluorescent Dyes; C549870:KLK3 protein, human; D007610:Kallikreins; D017430:Prostate-Specific Antigen
keywords: Cation exchange; Magnetic separation; Protein detection; Signal amplification; ZnSe/ZnS QDs