Molecularly imprinted poly(o-aminophenol)-based electrochemical sensor for the quantitative detection of a VP28 biomarker for white spot syndrome virus

• We present an optimized electrochemical sensor for quantitatively detecting VP28. • The sensor showed exceptional sensitivity and selectivity versus other platforms. • Stable performance was achieved in complex biological samples versus qPCR. • This is a cost-effective approach for monitoring viral infection in aquaculture. White spot syndrome virus (WSSV) is a deadly pathogen that can cause mass mortality within several days. VP28, known as a biomarker of WSSV, accounts for over half of the total envelope protein. It plays a crucial role in viral infection and is a useful diagnostic indicator for immunological detection. Here, we developed a molecularly imprinted polymer (MIP)-based electrochemical sensor using a gold nanostructured electrode and assessed its performance in detecting VP28. The electropolymerized poly(o-aminophenol) film supplies specific binding sites complementary to VP28. The molecularly imprinted cavities were examined using electrochemical analysis to confirm their ability to recognize the target molecule. The sensor generates a response signal through label-free sensing with a redox probe. It demonstrated a detection limit of 7.01 ng/mL (S/N = 3) and an imprinting factor 4.25 at 0.78–50 ng/mL concentrations. The selectivity study revealed a response signal 4.5 times higher for the target molecule than for interfering substances. Compared with the standard PCR method for real samples, the MIP-based sensor performed similarly according to virus concentration. These findings suggested that the MIP-based sensor is a simple and suitable alternative to conventional WSSV detection methods. This electrochemical sensing platform with electropolymerization of the molecularly imprinted polymer can promote the detection and monitoring of WSSV expressing VP28.