Abstract

Mitragyna speciosa (Korth.), commonly known as kratom, is a medicinal plant native to Southeast Asia. The plant contains several secondary metabolites, with mitragynine, an indole alkaloid, being the most common and important due to its pain-relieving effects. The limited commercial availability of mitragynine standards underscores the need for effective separation methodologies. Selective isolation is challenging because of the complexity of plant matrices. Molecularly imprinted polymers (MIP) have emerged as a viable approach to enhance selectivity in the separation. The goal of this project is to develop MIP as a selective sorbent for separating mitragynine from kratom. Synthesis optimization of MIP was performed by varying the initiator, temperature, and polymerization time. Sonication was employed for template removal, and infrared spectroscopy was used for characterization. Extraction was performed using reflux in methanol, followed by mitragynine identification. Column chromatography was conducted using MIP as the sorbent, and high-performance thin-layer chromatography was utilized to observe the separation patterns. MIP was successfully synthesized with a ratio of 1:3:20 using methacrylic acid as a monomer, with 0.3 mL of AIBN at 80°C for 24 hours as the optimal polymerization condition. The separation showed that the sorbent enhances mitragynine separation, primarily in fractions 2 and 3. Quantitative analysis estimated 36.7% isolation efficiency with a recovery of 3.313 mg of mitragynine. The results indicate that MIP can be used as a selective sorbent, offering a promising alternative to traditional separation approaches.

Key words: kratom, mitragynine, isolation, selective, molecularly imprinted polymer