TiO₂-embedded molecularly imprinted polymer as electrochemical sensor for ultrasensitive determination of...

The precise quantification and quality evaluation of glycopyrronium bromide (GLB), a long-acting muscarinic antagonist widely used in the treatment of chronic obstructive pulmonary disease, requires the development of advanced analytical methodologies capable of achieving high sensitivity, accuracy, and selectivity to ensure therapeutic efficacy and formulation integrity. This study aims to overcome the limitations of conventional methods by developing a rapid, cost-effective method for determining GLB.

To achieve this, titanium dioxide nanoparticles (TiO₂ NPs) were initially applied onto a glassy carbon electrode surface to provide an enhanced surface area and increased conductivity. Subsequently, a TiO₂ nanoparticle-supported molecularly imprinted polymer (MIP) film was synthesized via photopolymerization using GLB as the template molecule, 4-amminobenzoic acid (4-ABA) as the functional monomer, ethylene glycol dimethacrylate as the crosslinking agent, and 2-hydroxyethyl methacrylate (HEMA) as the basic monomer.

The optimized GLB/4-ABA@TiO₂ NPs/MIP- sensor demonstrated outstanding analytical performance, achieving ultra-low picomolar detection limits. The system exhibited superior selectivity (confirmed by high imprinting factor), excellent repeatability and reproducibility, and satisfactory stability. It was successfully applied to the accurate measurement of GLB in both commercial serum and pharmaceutical formulations.

The designed nanomaterial-embedded MIP-based electrochemical system presented here offers a highly successful, sensitive, and selective method for GLB determination. The work significantly advances knowledge in the field of analytical medicine and drug monitoring by providing a fast, robust alternative for routine clinical and quality-control tracking of GLB.