title: Proteolysis-mediated protection of gold nanoparticles for sensitive activity assay of peptidases.
abstract: Rapid, sensitive and quantitative assays for peptide hydrolysis enzymes are of paramount importance for drug development and in the diagnosis of disease. Here, we proposed a novel biosensor for sensitive and selective active screening of peptidases. This strategy relies on the proteolysis-mediated protection of gold nanoparticles (AuNPs) that were decorated with biotin-labeled substrate peptides and can be aggregated by streptavidin. Enzyme-mediated protection of AuNPs offers this strategy high specificity, and the use of AuNPs additionally allows a visual and homogeneous assay format, thus permitting improved simplicity and throughput of the assays. As a model case, desirable selectivity and sensitivity in peptidase assay were achieved in the active assays of pancreatic elastase with a wide linear response range from 0.005 to 0.10 U/mL and a detection limit of 0.003 U/mL. The results indicated that this strategy can offer a simple, robust and convenient platform for visualized peptidase activity analysis and related biochemical studies with high sensitivity and selectivity.
authors.affiliation: State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, PR China.
authors.forename: Dinh-Vu
authors.initials: DV
authors.lastname: Le
authors.forename: Van-Trong
authors.initials: VT
authors.lastname: Nguyen
authors.forename: Li-Juan
authors.initials: LJ
authors.lastname: Tang
authors.forename: Jian-Hui
authors.initials: JH
authors.lastname: Jiang
authors.forename: Ru-Qin
authors.initials: RQ
authors.lastname: Yu
authors.forename: Yu-Zhi
authors.initials: YZ
authors.lastname: Wang
mesh_terms: D000818:Animals; D015374:Biosensing Techniques / Q000379:methods*; D019921:Biotinylation; D057075:Enzyme Assays / Q000379:methods; D006046:Gold / Q000737:chemistry*; D057230:Limit of Detection; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010196:Pancreatic Elastase / Q000032:analysis / Q000378:metabolism*; D059748:Proteolysis; D013053:Spectrophotometry / Q000379:methods; D019809:Streptavidin / Q000737:chemistry; D013552:Swine
chemical_list: D006046:Gold; D019809:Streptavidin; D010196:Pancreatic Elastase