Preparation of protein imprinted microspheres using amphiphilic ionic liquid as stabilizer and emulsifier via miniemulsion polymerization

Design and preparation of functional materials for selective recognition of biomacromolecules such as proteins, DNA, viruses, and bacteria have always been extremely challenging due to their structure sensitivity. Regrettably, the structure stability of biomacromolecules in molecularly imprinted technology was rarely addressed. This paper presents an effective procedure for the facile preparation of bovine serum albumin (BSA) interfacial molecularly imprinted microspheres (IMIMs), using an imidazole-based amphiphilic ionic liquid (IL), which played a dual role of a stabilizer and emulsifier, via miniemulsion polymerization at 25 °C. In order to prove the stabilizing effect of IL on BSA, a conventional emulsifier sodium dodecyl sulfate (SDS), was also used as the emulsifier for comparison. Different characterization methods were employed to investigate the stability of BSA structure and track the experimental process. The results reveal that the destruction of structure of BSA by amphiphilic IL, 1-dodecyl-3-methylimidazolium chloride ([DMM]Cl), was much lower than that by SDS. Moreover, good selectivity of IMIMs-[DMM]Cl towards BSA was certified in the batch-wise and selectivity rebinding tests, in which an imprinting factor of 3.32 was obtained. This was superior to IMIMs-SDS and demonstrated to be a promising platform for recognition of protein with good specificity.