title: Simple and real-time colorimetric assay for glycosidases activity using functionalized gold nanoparticles and its application for inhibitor screening.
abstract: The development of real-time assays for enzymes has been receiving a great deal of attention in biomedical research recently. Self-immolative elimination is the spontaneous and irreversible disassembly of a multicomponent construct into its constituent fragments through a cascade of elimination processes, in response to external stimuli. Here, we report a simple and real-time colorimetric assay for glycosidases (β-galactosidase and β-glucosidase). Self-immolative elimination was utilized to release amines to give rise to aggregation and color change by electrostatic attraction after cleavage of the trigger by enzymes displayed on functionalized gold nanoparticles (Gal-Lip-AuNPs and Glc-Lip-AuNPs, where AuNPs denotes gold nanoparticles). The detection limits for β-galactosidase and β-glucosidase were as low as 9.2 and 22.3 nM at 20 min, and they improved slightly over time. Thus, glycosidase activity was detected successfully in real time, and this technique could be used for glycosidase inhibitor screening, based on real-time colorimetric variation.
authors.affiliation: Division of Advanced Science and Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Osaka 565-0871, Japan.
authors.forename: Zhanghua
authors.initials: Z
authors.lastname: Zeng
authors.forename: Shin
authors.initials: S
authors.lastname: Mizukami
authors.forename: Kazuya
authors.initials: K
authors.lastname: Kikuchi
mesh_terms: D003124:Colorimetry / Q000379:methods*; D004353:Drug Evaluation, Preclinical / Q000379:methods*; D057075:Enzyme Assays / Q000379:methods*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D006026:Glycoside Hydrolases / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D006046:Gold / Q000737:chemistry*; D057230:Limit of Detection; D055672:Static Electricity; D013438:Sulfhydryl Compounds / Q000737:chemistry; D013997:Time Factors
chemical_list: D004791:Enzyme Inhibitors; D013438:Sulfhydryl Compounds; D006046:Gold; D006026:Glycoside Hydrolases