Adsorption Isotherm and Kinetic Analysis of Sulfamethoxazole-Imprinted Polymers with two Functional Monomers using Bulk Polymerization

The analysis of adsorption isotherms and kinetics in molecularly imprinted polymers (MIPs) is vital for comprehending the interaction between target molecules and MIPs, thereby optimizing their functionality. These assessments offer valuable insights into the underlying mechanisms of adsorption, aid in the assessment of MIP synthesis parameters as well as enhancing the efficacy of MIP-based applications. Thus, this project aims to test the adsorption isotherm and kinetic analysis of sulfamethoxazole (SMX) antibiotic on MIPs using various adsorption models. The synthesis of MIPs was achieved using two monomers independently: methacrylic acid (MIP-MAA) and acrylamide (MIP-AA). Subsequently, the synthesized MIPs were characterized through surface morphology images using scanning electron microscope (SEM). The results from the four adsorption isotherm models applied showed that the Jovanovich model was the best fit followed by the Langmuir, Linear, and Freundlich models. Furthermore, among the three kinetic models evaluated, the Lagergren first-order model provided the best fit for MIP-MAA, while the pseudo-second-order model was most suitable for MIP-AA. The rate constant values were k1 = 0.54 min-1 for MIP-MAA and k2qe = 0.35 min-1 for MIP-AA at a concentration of 0.9 mM, respectively. These findings provide valuable insights into the adsorption mechanisms of SMX onto MIPs, showcasing MIPs as effective adsorbents for SMX that can be employed in efficient and precise methods for detecting antibiotic residues in various food products.