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

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.

Automated summary

This study develops a simple one-step protein immobilization strategy to attach proteins covalently on the sensor surface, ensuring close attachment to the transducer surface. The effectiveness of this strategy is evaluated by comparing it with silane chemistry, colorimetric assays, and field effect devices. The performance of this methodology is also evaluated for the detection of glucose oxidation using a field effect device. Overall, the developed immobilization strategy avoids the effects of the debye length and improves the performance of the biosensor.