Abstract
Molecularly imprinted polymers (MIPs) are smart polymers that can be served as biomimic enzymes for biosensor applications. Pharmaceutical and personal care products (PPCPs) are a diverse group of environmental chemicals that have been captured much attention. Acetaminophen and acetylsalicylic acid are widely used in pharmaceutical factories and released into the environments as PPCPs. However, it is difficult to find suitable enzymes or active receptors that are capable of effectively recognizing acetaminophen and acetylsalicylic acid. In this study, therefore, a new procedure for fabricating the acetaminophen and acetylsalicylic acid-based molecularly imprinted polymer microspheres were developed. Acetaminophen and acetylsalicylic acid-imprinted polymer was prepared using precipitation polymerization by non-covalent binding. Precipitation imprinting method can directly produce MIP microspheres using relative simple polymerization processes, which is environmentally friendly and can preserve active sites for imprinting. Acetaminophen and acetylsalicylic acid were used as the template, respectively. After adding methacrylic acid, trimethylpropane trimethacrylate and azobisisobutyronitrile, solutions were heated to 60 °C for 24 hours to form polymers. The average particle sizes of acetaminophen and acetylsalicylic acid-imprinted microspheres, determined by dynamic light scattering were in the range 100 ∼ 200 nm. UV/vis spectroscopic results showed that acetaminophen and acetylsalicylic acid can be completely removed by methanol. Binding capacity showed that the acetaminophen and acetylsalicylic acid-imprinted polymers have higher selectivity than that of control polymer. The effect of porogen on specificity was also evaluated and found that toluene can produce larger particle size of MIP microsphere than that by acetonitrile. In addition, column results obtained in this study showed that the developed MIP microspheres can separate accurately from analogous compounds and have the potential to effectively detect and separate acetaminophen and acetylsalicylic acid.