Photoresponsive molecularly imprinted dendrimer-based magnetic nanoparticles for photo-regulated selective separation of azathioprine

This research describes the development of a poly (amidoamine) (PAMAM) dendrimer-based photoresponsive molecularly imprinted polymers (P-MIPs) for selective separation and determination of azathioprine. This study is the first involving a PAMAM dendrimer-coated magnetic nanoparticles (MNPs) used during the imprinting process to enhance a number of recognition sites in the polymer matrix to advance the recognition ability. The photoresponsive MIP was fabricated using azathioprine as the template, water-soluble 5-[(4-(methacryloyloxy) phenyl) diazenyl] isophthalic acid as the functional monomer, and ethylene glycol dimethacrylate as the cross-linker. The dendrimer-magnetic nanoparticles and PAMAM dendrimer-based P-MIPs were characterized by different spectroscopic and nano structural techniques. Quantitatively release and uptake of azathioprine from the P-MIP is photoregulated by alternate irradiation with ultraviolet and visible light. This means that trans–cis isomerization could regulate the affinity for azathioprine and azobenzene groups placed inside the binding sites. Hence, this material could be used as a chemical sorbent. The recoveries for analyte were higher than 95% and relative standard deviation values were found to be in the range of 1.24–1.72%, indicating that the prepared nano-sorbent has high accuracy and precision for determining trace of azathioprine in complex biological and pharmaceutical samples.