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.