Acute kidney injury (AKI) is a condition resulting from the acute loss of the kidney's function to eliminate waste products from the body, leading to severe life-threatening complications. Therefore, rapid and accurate diagnosis is critically important. Currently, AKI diagnosis primarily relies on the measurement of serum creatinine (SCr) levels and urine output. However, these indicators require a relatively long period of time to identify the risk of AKI, resulting in delayed treatment.

In this study, an electrochemical immunosensor was developed for the detection of Tissue Inhibitor of Metalloproteinases 2 (TIMP2) as an early biomarker of AKI. The electrochemical characterization was performed using cyclic voltammetry (CV), square wave voltammetry (SWV), and electrochemical impedance spectroscopy (EIS), while physical characterization was performed using contact angle measurement (CAM). Subsequently, optimal conditions for TIMP2 detection were evaluated using SWV and EIS, including the mercaptopropionic acid (MPA) incubation time, antibody concentration, and TIMP2 incubation time.

The optimal conditions were determined to be an MPA incubation time of 3 h, an antibody concentration of 1 μg/mL, and a TIMP2 incubation time of 15 min. Under these optimized conditions, the results demonstrated that the immunosensor exhibited good sensitivity and specificity for TIMP2 detection. This research demonstrates the potential application of the developed immunosensor for TIMP2 detection. Future work will focus on optimizing additional parameters such as electrochemical parameters, pH, and temperature, further evaluating sensitivity and specificity, and validating the immunosensor with real samples.

This approach may provide an alternative strategy for the early identification and monitoring of acute kidney injury.