Designing of molecularly imprinted polymer with carboxylic acid functionality for chiral separation of (±)‐3,4‐methylenedioxymethamphetamine

Abstract

AbstractIn this work, we discuss the development of a long‐lasting enantioselective material for the effective enantio‐recognition of S‐3,4‐methylenedioxymethamphetamine (S‐MDMA) and chiral separation of the (±)‐MDMA racemate using a crosslinked poly(acrylic acid‐4‐vinylpyridine) copolymer. The first step was the synthesis and characterization of an acryloyl‐S‐MDMA amide. After that, the free radical initiator azobisisobutyronitrile was used to copolymerize the synthesized chiral amide with 4‐vinylpyridine and divinylbenzene. The incorporated S‐MDMA species were extracted from the polymeric particles by heating them with sodium hydroxide, followed by rinsing with hydrochloric acid. This developed the molecularly imprinted S‐MDMA particles, which were visualized with a scanning electron microscope and Fourier transform infrared spectroscopy. The selectivity parameters indicated a higher affinity of the fabricated S‐MDMA imprinted particles toward S‐MDMA, around 10‐fold higher than that related to R‐MDMA. Results from Langmuir adsorption experiments at pH 6 demonstrated a maximal capacity of 142 mg g−1. In addition, the values of enantiomeric excess were found to be 94.5% and 79.4% for R‐ and S‐MDMA in the loading and eluant solutions, respectively, after optical separation was done using the column technique. © 2023 Society of Industrial Chemistry.