Tailoring carboxymethyl guargum hydrogel with nanosilica for sustained transdermal release of diclofenac sodium

Carboxymethyl guar gum (CMG) was structurally tailored with aqueous-nanosilica sol for controlled transdermal release of diclofenac sodium. Nanosilica was administered in low to moderately high concentration range to synthesize various, novel CMG-silica hybrid nanocomposites. Spectroscopy together with thermogravimetry, morphology, swelling and rheological studies proved that 1 wt% nanosilica content was the best physical formulation. The drug release studies from different hydrogel nanocomposites exhibited slower release than neat CMG. 1 wt% nanosilica loaded hydrogel nanocomposite gave slowest but steady release profile among all other nanocomposites due to its highly viscous nature owing to most compact microstructure. (C) 2011 Elsevier Ltd. All rights reserved.