Single‐Step Primary Amine Synthesis on Proton Sensitive Nanofilms to Overcome Its Debye Length Limitations

• Published in: Advanced materials interfaces Vol. 10; no. 21
• Main Authors: Yang, Chia‐Ming, Liu, Hui‐Ling, Ho, Chih‐Ching, Tsai, Hsieh‐Fu, Bhalla, Nikhil
• Format: Journal Article
• Language: English
• Published: Weinheim John Wiley & Sons, Inc 01.07.2023; Wiley-VCH
• Subjects: amines; Binding; Biosensors; Charged particles; Debye length; Electric fields; field‐effect transistor; Hydrogen peroxide; Immobilization; Ions; Oxidation; Particle decay; Performance enhancement; Performance evaluation; Proteins; Transducers
• ISSN: 2196-7350; 2196-7350
• DOI: 10.1002/admi.202300080

The debye length is a measure of the distance over which the electric field of a charged particle decays in an electrolyte solution. If the binding of the analyte to the surface of the transducer is too far away from the surface, the electric field to the analyte may decay over a distance greater than the debye length thereby reducing the sensitivity of the measurement. In this context, this study has developed a simple one‐step protein immobilization strategy to covalently attach proteins on the sensor surface. Our binding strategy, which uses hydrogen peroxide (H2O2) ensures that the analyte is attached as close as possible to the transducer surface. This study evaluates our findings by comparing our strategy with silane chemistry and elucidating the debye length effects with colorimetric assays and field effect devices. Additionally, as a case study, we also evaluated the performance of our methodology for the detection of glucose oxidation by a field effect device. Overall, the developed immobilization strategy avoids the effects of the debye length and improves the performance of the biosensor. The study demonstrates how to develop a short length biorecognition layer on the top surfaces of bio/chemical sensors. The short length biorecognition layer is essential to mitigate the debye length effects within the solid‐liquid interface of the analyte/ sensor‐surface interaction.