Development of molecularly imprinted polymers for disposable pipette extraction of the Bisphenol A in biological samples and analysis by GC-MS

Abstract

Bisphenol A (BPA) is widely applied to produce polycarbonate, polymers, and epoxy resins. Because polycarbonate is transparent and highly mechanically and thermally resistant, it is commonly used to manufacture baby bottles, water bottles, sports equipment, medical and dental devices, eyeglass lenses, CDs and DVDs, home appliances, and food packaging. Epoxy resins are part of the lining of canned foods packaging. BPA is a bisphenol-glycidyl-methacrylate (Bis-GMA) and bisphenol dimethacrylate (Bis-DMA) precursor in the production of resins employed as dental sealants. BPA is toxic, because it acts as an endocrine disruptor that mimics endocrine hormones, and interferes with their secretion, transport, bonds, and/or elimination. Endocrine disruptors affect the reproductive, cardiovascular and neuroendocrine systems, and they also may be carcinogenic.Toxicological analysis aims to identify and evaluate the effects of exposure of individuals to toxic agents. Biological fluids are used as samples for these analyses. Considering the complexity of these fluids, sample preparation is an essential step to increase the selectivity and sensitivity of the analytical method. The analytes are isolated and pre-concentrated before the sample is introduced into the analytical system. Modern analytical chemistry has been concerned with simplification via miniaturization of analytical systems. Miniaturization facilitates hyphenation techniques, reducing organic solvent consumption, sample volume, and analysis time. Additionally, it employs environmentally friendly technologies, which is a means to preventively care for the environment.Disposable pipette extraction (DPX) consists in a technique that uses a small quantity of solid phase dispersive inside a tip. The solid phase is located between two filters. The silica matrixes disilane (C2), octylsilane (C8), and octadecylsilane (C18), among other phases, are commercially available as adsorbents. The highly selective and stable Molecular Imprinted Polymers (MIPs) have also gained attention as alternative sorbent materials.The MIPs consist of a three-dimensional polymer network with cavities that can selectively recognize the target analyte. This polymer network is synthesized around the template molecule (analyte), and the cavity is formed after removing this molecule by washing. The interaction between the analyte and the MIP resembles the antigen-antibody interaction. Among other advantages, the synthesis of MIP by the sol-gel process allows porosity control as well as particle size and shape. Moreover, MIPs exhibit high thermal stability.In this context, this work aims to synthesize the MIP phase (sol-gel) for the DPX of bisphenol A in urine and saliva samples for analysis by gas chromatography-mass spectrometry (GC-MS).