Corrosion protection in reinforced concrete structures exposed to aggressive environments remains a critical challenge in civil and architectural engineering. One promising approach involves the application of corrosion-inhibiting monolayers on the reinforcement, such as those formed using 4-aminobenzoic acid. Two methods have previously been employed to generate these monolayers: one relying on the adhesion of an organic compound and the other utilising an externally modified approach via electrolysis. This study assesses the influence of this treatment on the steel–concrete bond strength and durability, both critical properties for the structural performance of reinforced concrete under service conditions. For this purpose, pull-out tests were performed on specimens subjected to load–unload cycles to analyse bond behaviour and monolayer integrity. The results indicate that these treatments do not adversely affect the bond strength between reinforcement and concrete. Furthermore, the rebars treated with the inhibitor exhibit less corrosion damage than the untreated rebars. This fact is particularly significant in the rebars treated using the natural adhesion method, with the steel section loss being 32–37% lower than in the untreated rebars. These findings support the feasibility of applying this treatment without compromising structural functionality.

Electrochemical Impedance Spectroscopy (EIS) is widely used in nucleic-acid-based sensing due to its sensitivity, label-free operation, and compatibility with miniaturized platforms. In such systems, DNA hybridization at the electrode surface constitutes a well-established recognition mechanism, producing measurable interfacial impedance changes. Here, we present a comparative study of two-electrode and three-electrode configurations for impedimetric sensors based on DNA hybridization using a Candida albicans-related DNA sequence as a model system, where the three-electrode setup incorporates a silver pseudo-reference electrode (Ag) that is better suited for bio-applications. Screen-printed gold electrodes were functionalized with thiol-modified single-stranded DNA probes, and complementary DNA targets were used to induce controlled hybridization over a concentration range of 0.1–100 nM (0.73–730 pg/µL). Impedance spectra were analyzed using different transduction metrics, with the relative Nyquist area providing the most robust calibration performance (R2 = 0.95 and 0.96 for the two-electrode and three-electrode configurations, respectively). A systematic analysis of temporal signal drift under repeated measurements revealed significantly improved stability for the two-electrode configuration, exhibiting approximately half the cumulative instability of the three-electrode setup. These results demonstrate that while both electrode configurations provide comparable calibration performance, the two-electrode setup offers reduced temporal signal drift and improved stability over time, highlighting the combined importance of electrode configuration and drift analysis for practical impedimetric sensing.