چکیده (انگلیسی):

This article investigates enhancement of the dissolution
profile of valdecoxib using solid dispersion with PVP. The
article also describes the preparation of fast-dissolving tablets
of valdecoxib by using a high amount of superdisintegrants.
A phase solubility method was used to evaluate the
effect of various water-soluble polymers on aqueous solubility
of valdecoxib. Polyvinyl pyrrolidone (PVP K-30) was
selected and solid dispersions were prepared by the method
of kneading. Dissolution studies using the USP paddle
method were performed for solid dispersions of valdecoxib.
Infrared (IR) spectroscopy, differential scanning calorimetry
(DSC), and x-ray diffractometry (XRD) were performed to
identify the physicochemical interaction between drug and
carrier, hence its effect on dissolution. Tablets were formulated
containing solid dispersion products and compared
with commercial products. IR spectroscopy, XRD, and DSC
showed no change in the crystal structure of valdecoxib. Dissolution
of valdecoxib improved significantly in solid dispersion
products (G 85% in 5 minutes). Tablets containing
solid dispersion exhibited better dissolution profile than
commercial tablets. Thus, the solid dispersion technique
can be successfully used for improvement of dissolution of
valdecoxib.