In horseradish peroxidase (HRP)-based electrochemical immunosensing, an appropriate HRP substrate needs to be chosen to obtain a high electrochemical signal-to-background ratio. This is limited by the unwanted electrochemical reduction of HO, oxidation of the substrate, and the slow electrochemical reduction of the product. Herein, we report acetaminophen (AMP) as a new HRP substrate that allows for highly sensitive immunosensing. Electrochemical behavior and immunosensing performance using AMP are compared with those using the most popular HRP substrate, hydroquinone (HQ). To maintain a high electrocatalytic activity even at an electrode modified with an immunosensing layer, an indium tin oxide electrode partially modified with reduced graphene oxide is employed. AMP allows for a higher signal-to-background ratio than HQ, because the formal potential of AMP is 0.28 V higher than that of HQ and the redox reaction of AMP is as reversible as that of HQ, resulting in a lower detection limit in a sandwich-type immunoassay using AMP for thyroid-stimulating hormone detection. The calculated detection limit is ~0.2 pg/mL. The use of AMP as an HRP substrate is especially promising for highly sensitive electrochemical immunoassays.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.bios.2020.112337 | DOI Listing |
Talanta
December 2024
State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China. Electronic address:
Herein, we present a colorimetric sensing strategy for the identification and quantification of tumor-associated miRNAs based on dual DNAzyme amplification. In this sensing ensemble, the substrate portion of the Pb-dependent 8-17 DNAzyme combines with the G-quadruplex portion to form a hairpin substrate strand. The two split 8-17 DNAzyme strands are partially complementary to the substrate strand and serve as a recognition unit for binding the target miRNA.
View Article and Find Full Text PDFNanoscale
December 2024
Department of Pharmaceutical Analysis, School of Pharmacy, China Pharmaceutical University, Nanjing 211198, China.
In biosensing analysis, the activity of enzyme systems is limited by their fragility, and substrates catalyzed by monoenzymes tend to undergo spontaneous decomposition during ineffective mass transfer processes. In this study, we propose a novel strategy to encapsulate the glucose oxidase and horseradish peroxidase (GOx&HRP) cascade catalytic system within the hydrophilic zeolite imidazole framework ZIF-90. By leveraging the specific pore structure of ZIF-90, we effectively immobilized GOx and HRP molecules in their three-dimensional conformations, which improved the catalytic activity of the encapsulated enzymes compared with that of free GOx and HRP in various harsh environments.
View Article and Find Full Text PDFJ Nanobiotechnology
November 2024
Clinical Medical Laboratory Center, Gaogang Branch, Taizhou School of Clinical Medicine, Nanjing Medical University, The Affiliated Taizhou People's Hospital of Nanjing Medical University, Taizhou, 225300, China.
Talanta
March 2025
Department of Biotechnology Engineering, Faculty of Engineering Science, Ben-Gurion University of the Negev, Beer-Sheva, 8410501, Israel. Electronic address:
Hybridoma technology remains a cornerstone of monoclonal antibody (mAb) discovery. Classical screening practices such as ELISA, western blot, and dot blot require laborious, time-consuming procedures, rendering them inefficient in time-restricted decision-making. Additionally, due to these assays' practical and technical limitations, specificity testing of the mAbs is usually omitted during the primary screening of hybridoma libraries.
View Article and Find Full Text PDFJ Hazard Mater
November 2024
School of Food Science and Technology, Shihezi University, Shihezi, Xinjiang 832003, China; Key Laboratory of Agricultural Product Processing and Quality Control of Specialty(Co-construction by Ministry and Province), School of Food Science and Technology, Shihezi University, Shihezi, China; Key Laboratory for Food Nutrition and Safety Control of Xinjiang Production and Construction Corps, School of Food Science and Technology, Shihezi University, Shihezi, China. Electronic address:
The development of a versatile platform for bacterial assay and elimination is urgently needed due to the danger that bacteria pose to human life. Here, we synthesized a trimetallic deposition and horseradish peroxidase (HRP)-embedded porous coordination network-224 hybrid nanozymes (PCN-224 @AuPdPt@HRP) with outstanding peroxidase activity and fluorescence quenching ability. On this basis, we designed a dual recognition strategy-driven colorimetric-fluorescence dual-mode detection platform using Listeria monocytogenes as a pattern analyte.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!