Theoretical screening and electrochemical sensor for determination of norepinephrine using a molecularly imprinted poly (3-amiophenylboronic acid)

Norepinephrine (NE) is the primary catecholamine (CA) of interest in the medical field, as it plays a key role in regulating the hormonal and neurological systems. Some NE concentration dysfunction can lead to a number of serious physical conditions. As a result, quick and sensitive NE detection is most critical in medical technology. Thus, in this research, a molecularly imprinted polymer (MIP) was used to create an electrochemical sensor for the selective detection of NE. Prior to this, functional monomers were chosen through molecular modeling utilizing molecular mechanics and quantum mechanics computations. According to these studies, the 3-aminophenylboronic acid (3-APBA) functional monomer produces the most stable complex with NE in molecular modeling calculations. Based on this, by electropolymerizing 3-APBA in the presence of the template molecule NE, an imprinting polymer film is formed on the screen-printed carbon electrode (SPCE) surface. Stepwise fabrication of imprinted polymer films was examined through differential pulse voltammetry (DPV), cyclic voltammetry (CV), scanning electron microscopy (SEM), and electrochemical impedance spectroscopy (EIS). The performance of the electrochemical NE sensor removal and rebinding levels of the template was studied and optimized. The selectivity for NE was confirmed by using interference studies of small molecules like dopamine, tyrosine, and serotonin. Under optimum levels, the fabricated MIP sensor had a broad linear range over NE concentrations of 0.1 pM–5 pM; sensitivity: 0.004 mA pM⁻¹; limit of detection: 0.03 pM. It is noteworthy that the newly created MIP sensor was effectively validated for NE detection in plasma samples.