Beck, Franziska and Horn, Carina and Baeumner, Antje J. (2022) Ag nanoparticles outperform Au nanoparticles for the use as label in electrochemical point-of-care sensors. ANALYTICAL AND BIOANALYTICAL CHEMISTRY, 414 (1). pp. 475-483. ISSN 1618-2642, 1618-2650
Full text not available from this repository. (Request a copy)Abstract
Electrochemical immunosensors enable rapid analyte quantification in small sample volumes, and have been demonstrated to provide high sensitivity and selectivity, simple miniaturization, and easy sensor production strategies. As a point-of-care (POC) format, user-friendliness is equally important and most often not combinable with high sensitivity. As such, we demonstrate here that a sequence of metal oxidation and reduction, followed by stripping via differential pulse voltammetry (DPV), provides lowest limits of detection within a 2-min automatic measurement. In exchanging gold nanoparticles (AuNPs), which dominate in the development of POC sensors, with silver nanoparticles (AgNPs), not only better sensitivity was obtained, but more importantly, the assay protocol could be simplified to match POC requirements. Specifically, we studied both nanoparticles as reporter labels in a sandwich immunoassay with the blood protein biomarker NT-proBNP. For both kinds of nanoparticles, the dose-response curves easily covered the ng center dot mL(-1) range. The mean standard deviation of all measurements of 17% (n >= 4) and a limit of detection of 26 ng center dot mL(-1) were achieved using AuNPs, but their detection requires addition of HCl, which is impossible in a POC format. In contrast, since AgNPs are electrochemically less stable, they enabled a simplified assay protocol and provided even lower LODs of 4.0 ng center dot mL(-1) in buffer and 4.7 ng center dot mL(-1) in human serum while maintaining the same or even better assay reliability, storage stability, and easy antibody immobilization protocols. Thus, in direct comparison, AgNPs clearly outperform AuNPs in desirable POC electrochemical assays and should gain much more attention in the future development of such biosensors.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | ; Electrochemical biosensor; Silver nanoparticle; Gold nanoparticle; Blood analysis; DPV |
| Subjects: | 500 Science > 540 Chemistry & allied sciences |
| Divisions: | Chemistry and Pharmacy > Institut für Analytische Chemie, Chemo- und Biosensorik > Chemo- und Biosensorik (Prof. Antje J. Bäumner, formerly Prof. Wolfbeis) |
| Depositing User: | Dr. Gernot Deinzer |
| Date Deposited: | 09 Aug 2022 12:39 |
| Last Modified: | 09 Aug 2022 12:39 |
| URI: | https://pred.uni-regensburg.de/id/eprint/46232 |
Actions (login required)
 |
View Item |
