Abstract: Highly specific and selective artificial recognition units for aspirin was fabricated on polymer-nanocomposites (MWCNT-MIP) making use of molecular imprinting technology. The products were characterised using Fourier-transform infrared spectroscopy, powder X-Ray diffraction studies, thermogravimetric analysis, scanning electron microscopic and tunnelling electron microscopic techniques. The maximum saturated binding capacity (Qmax) for MW CNT-MIP was obtained as 0.644mmolg-1 with an 82% increase as compared with the non-imprinted counterpart (MWCNT-NIP). MW CNT-MIP shows a high regression coefficient value (R2=0.999) for Langmuir adsorption isotherm indicating enhanced homogeneity than the corresponding bulk MIP (R2=0.977). The rebinding process obeys second order kinetics with rapid template binding demonstrating the effective formation of print cavities on the surface of sorbent. Also, the theoretical and experimental values for Qe from second order kinetic data were found to be almost similar even at different temperatures. The optimized rebinding parameters of the nanosorbents were applied for the separation of aspirin from its closely related structural analogues and these studies indicated a higher relative selectivity coefficient for MW CNT-MIP towards aspirin than the bulk MIP. Further MWCNT-MIP is found to have 100% reproducibility upto four adsorption-desorption cycles.
Template and target information: aspirin, acetylsalicylic acid
Author keywords: molecular imprinting, Multiwalled carbon nanotubes, selective recognition, Regeneration, Aspirin, specificity