title: Reagent-less electrogenerated chemiluminescence peptide-based biosensor for the determination of prostate-specific antigen.
abstract: A novel electrogenerated chemiluminescence peptide-based (ECL-PB) biosensor for highly sensitive and selective determination of prostate-specific antigen (PSA) was developed. A helix peptide (CHSSKLQK) was served as a molecular recognition element and ruthenium bis(2,2'-bipyridine) (2,2'-bipyridine-4,4'-dicarboxylic acid)-N-hydroxysuccinimide ester (Ru(bpy)(2)(dcbpy)NHS) was used as an ECL label. The helix peptide was labeled with the ECL label at NH(2)-containing lysine and utilized as ECL probe (Ru-peptide). The ECL-PB biosensor was fabricated by immobilizing the ECL probe onto a gold electrode surface via self-assembling technique through a thiol-containing cysteine at the end of the peptide. The principle of ECL measurement is based on the specific proteolytic cleavage event of Ru-peptide on the gold electrode surface in the presence of PSA, resulting in a decrease of ECL signal. The decreased ECL intensity was directly linear to the concentration of PSA in the range from 1.0×10(-10) g/mL to 8.0×10(-9) g/mL with a detection limit of 3.8×10(-11) g/mL. This work demonstrates that the direct transduction of peptide cleavage events into an ECL signal provides a simple and sensitive method for detecting target protein.
authors.affiliation: Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710062, PR China. honglanqi@snnu.edu.cn
authors.forename: Honglan
authors.initials: H
authors.lastname: Qi
authors.forename: Chen
authors.initials: C
authors.lastname: Wang
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Qiu
authors.forename: Qiang
authors.initials: Q
authors.lastname: Gao
authors.forename: Chengxiao
authors.initials: C
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D015374:Biosensing Techniques / Q000379:methods*; D004563:Electrochemistry; D006801:Humans; D055767:Immobilized Proteins / Q000737:chemistry / Q000378:metabolism; D007700:Kinetics; D057230:Limit of Detection; D008163:Luminescent Measurements / Q000379:methods*; D008958:Models, Molecular; D008968:Molecular Conformation; D009842:Oligopeptides / Q000737:chemistry* / Q000378:metabolism; D017430:Prostate-Specific Antigen / Q000032:analysis* / Q000378:metabolism
chemical_list: D055767:Immobilized Proteins; D009842:Oligopeptides; D017430:Prostate-Specific Antigen