Title: Nanoparticulate molecularly imprinted poly(acrylic acid) as potential stationary phase for chiral separation of ofloxacin
Authors: Soma Chakraborty; Cheem Conanan Razonabe; Modesto Tan Chua
Addresses: Department of Chemistry, Ateneo De Manila University, Loyola Heights, QC 1108, Philippines ' Department of Chemistry, Ateneo De Manila University, Loyola Heights, QC 1108, Philippines ' Department of Chemistry, Ateneo De Manila University, Loyola Heights, QC 1108, Philippines; Philippine Institute of Pure and Applied Chemistry, Loyola Heights, QC 1108, Philippines
Abstract: A novel method for the synthesis of nano size molecularly imprinted poly(acrylic acid) (PAA) by reverse microemulsion technique has been reported. Molecularly-imprinted PAA were also synthesised by bulk polymerisation. Levofloxacin (LOfx) (S ofloxacin) was used as the template for imprinting. Scanning electron micrograph and dynamic light scattering profile revealed that emulsion polymerisation resulted in nano size molecularly-imprinted polymer (MIP) with narrow size distribution whereas bulk polymerisation resulted in irregular shaped micron size particles. Rebinding of LOfx was highest for nano MIPs as compared to micron MIPs and the non-imprinted polymers (NIP). Imprinting factor which indicates selective binding capacity was maximum for the nano system both in water as well as in acetonitrile. Circular dichroism spectroscopy showed that nano and micron size MIPs could selectively bind to chiral LOfx from its racemic mixture (R, S ofloxacin). However, selectivity of nano MIPs was superior to micro MIPs. TLC plate prepared using nano MIP as the stationary phase could also isolate LOfx from Ofx as two distinct spots on the TLC plate, well separated spots were not visible when microsize or non-imprinted polymers were used as the stationary phase.
Keywords: poly(acrylic acid); PAA; nanoMIP; ofloxacin; levofloxacin; chiral separation; nanoparticles; nanotechnology; molecular imprinting.
International Journal of Nano and Biomaterials, 2014 Vol.5 No.2/3, pp.152 - 164
Received: 10 Dec 2013
Accepted: 24 Mar 2014
Published online: 24 Jan 2015 *