A label-free and washing-free method to detect biological thiols on a personal glucose meter utilizing glucose oxidase-mimicking activity of gold nanoparticles

• Published in: Biosensors & bioelectronics Vol. 250; p. 116019
• Main Authors: Lee, Sang Mo, Kim, Hyoyong, Li, Pei, Park, Hyun Gyu
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 15.04.2024
• Subjects: Biological thiol; Glucose oxidase-mimicking activity; Gold nanoparticle; Personal glucose meter; Personal glucose meter; Glucose oxidase-mimicking activity; Biological thiol; Gold nanoparticle
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/j.bios.2024.116019

We herein developed a label-free and washing-free method to detect biological thiols (biothiols) on a personal glucose meter (PGM) utilizing the intrinsic glucose oxidase (GOx)-mimicking activity of gold nanoparticles (AuNPs). By focusing on the fact that this activity could be diminished by target biothiols through their binding onto the AuNP surface, we correlated the concentration of biothiols with that of glucose readily measurable on a PGM and successfully determined cysteine (Cys), homocysteine (Hcy), and glutathione (GSH) down to 0.116, 0.059, and 0.133 μM, respectively, with high specificity against non-target biomolecules. We further demonstrated its practical applicability by reliably detecting target biothiol in heterogeneous human serum. Due to the meritorious features of PGM such as simplicity, portability, and cost-effectiveness, we believe that this work could serve as a powerful platform for biothiol detection in point-of-care settings. •A label-free and washing-free PGM-based biothiol detection strategy was developed.•By utilizing GOx activity of bare AuNP, we successfully correlated biothiols with glucose readily measurable on a PGM.•Based on the straightforward strategy, total biothiol level contained in heterogeneous human serum was accurately determined.•We demonstrated novel approach to detect non-glucose analytes on a PGM and could advance the PGM-based detection strategies.