2024 AIChE Annual Meeting
(618a) Got Milk? Detecting Antibiotics with a Molecularly Imprinted Polymer Based Sensor
Sulfonamides, commonly used in veterinary medicine for the treatment and prevention of bacterial infections, can accumulate in dairy products from cattle, posing a public health concern. Several regulatory agencies around the world have established Maximum Residue Limits (MRLs), providing a demand for sensitive detection methods for these contaminants in milk, a complex mixture. In this study, a molecularly imprinted polymer (MIP) based electrochemical sensor was developed for sulfamethoxazole (SMX) detection. A systematic study of the electrochemical properties of SMX was conducted to identify an optimal detection solution that enhances the electroactivity of SMX within the MIP film. The monomer selected, pyrrole, was electropolymerized and overoxidized on a screen-printed electrode using cyclic voltammetry (CV) in the presence of a supporting electrolyte. An optimization of monomer and template concentrations, electropolymerization cycles, and pH was performed to achieve the desired selective analyte recognition. A comparison of the MIP and non-imprinted polymer (NIP) was done to validate the proposed sensor’s characteristics. A nanomaterial layer under the MIP layer was used to boost the electroactive signal of SMX oxidizing, providing high sensitivity and a low limit of detection. Selectivity was investigated against other sulfonamides and other veterinary drugs that may be present in milk. Reusability, sensitivity, and reproducibility were also investigated. Lastly, the MIP-based SMX electrochemical sensor was integrated with a portable potentiostat to detect SMX in real milk samples. It holds great promise to detect SMX in dairy products in low-resources settings.