Molecularly Imprinted Polymer/Anodic Aluminum Oxide Nanocomposite Sensing Electrode for Low-Concentration Troponin T Detection for Patient Monitoring Applications

Various clinical studies have shown that myocardial troponin T (cTnT) is highly correlated with acute myocardial infarction (AMI). A highly sensitive molecularly imprinted polymer (MIP) sensing electrode for the detection of cTnT in patients' blood serum can enable cost-effective, rapid, and real-time testing for patients requiring intensive care. However, the existing MIP-based sensing electrode does not perform well for low-concentration detection of cTnT (<0.2 ng/mL). In this study, a new type of sensing electrode, an anodic aluminum oxide molecularly imprinted (MIP/AAO) nanocomposite electrode is developed. By incorporating the AAO structure, i.e., one-dimensional (1D) pillars, through a semiconductor-compatible process, the new electrode exhibits a great performance improvement, higher sensitivity of 1.08 × 10^-4 and 4.25 × 10^-4 in the low (<0.03 ng/mL)- and high-concentration regions, respectively, and a lower limit of detection (LoD) of 5.34 pg/mL. Because the composite electrode can maintain a linear characteristic in the measurement range of low-concentration cTnT, it can effectively improve the accuracy and reduce the error in cTnT measurement. In addition, the novel sensing electrode exhibits good reusability and specificity.