Field-Assisted Non-Faradaic Electrical Detection of Salmonella DNA Using an APTES- Modified Aluminum Interdigitated Electrode Platform
Discuss this preprint
Start a discussion What are Sciety discussions?Listed in
This article is not in any list yet, why not save it to one of your lists.Abstract
A label-free electrical biosensor based on an aluminum interdigitated electrode (Al-IDE) platform is described for the selective detection of Salmonella DNA using probe-target hybridization. The device was built using standard microfabrication procedures and functionalized with 3-aminopropyltriethoxysilane (APTES) to allow for stable probe immobilization. Direct current-voltage (I-V) measurements were used for detection under non-Faradaic conditions, which eliminated the requirement for redox mediators or sophisticated impedance analysis. The sensor demonstrated obvious voltage-dependent signal amplification, with the fully complementary target resulting in a 37.27% rise in current relative to the probe baseline at 1.0 V, compared to 28.57% and 3.11% for mismatched and non-complementary sequences. The statistical analysis revealed considerable discrimination across target groups (F(2,27) = 848.15, p < 0.0001, η² = 0.984), indicating great sequence selectivity. The enhanced electrical response is due to field-assisted modulation of the electric double layer (EDL) and higher interfacial charge density caused by DNA hybridization. Compared to impedance-based and redox-mediated biosensors, the suggested platform provides a more straightforward detection technique with competitive selectivity and minimum instrumentation needs. The findings demonstrate the utility of Al-IDE devices as scalable and cost-effective platforms for portable nucleic acid detection in food safety and point-of-care diagnostics.
