Preparation and physicochemical characterization of solid dispersions of piroxicam with phospholipids

Solid dispersions of piroxicam with dimyristoylphosphatidylcholine [DMPC], dipalmitoylphosphatidylcholine [DSPC] and distearoylphosphatidylcholine [DSPC] in ratios of 20:1, 10:1 and 5:1 [drug-to-phospholipids w/w], were prepared by the solvent evaporation method. Coprecipitation was done from a chloroform solution of the appropriate quantities of piroxicam and each phospholipid according to the previously mentioned w/w ratios. The physicochemical characteristics of piroxicam-phospholipids coprecipitates were evaluated using differential scanning calorimetric analysis [DSC], X- ray diffraction analysis [XRD] and Fourier transform infrared analysis [FTlR]. Results were compared with the pure drug and the corresponding physical mixtures in the same weight ratios

Enhancement of dissolution and bioavailability of firoxicam via solid dispersion with phospholipids

In this work physical mixtures [PMs] and coprecipitates [COPPTs] of piroxicam [PIR] with each of L-alpha-dimyristoylphosphatidylcholine [DPPC] and L-alpha-distearoylphosphatidycholine [DSPC] in ratios of 20:1, 10:1 and 5:1 [drug-to-phospholipids w/w] were prepared. The effect of the method of preparation, the type of phospholipids [PL] and the drug-to-PL w/w ratios on the rate and extent of dissolution of PIR was investigated. The effect of the previously mentioned factors on the dissolution efficiency [DE%] was analyzed using two-way analysis of variance [ANOVA]. The most significant effect on the dissolution rate and extent was due to the method of preparation followed by the drug-to-PL ratio and finally the PL type. All PIR-PL systems improved the dissolution rate of piroxicam, but coprecipitates of 5:1 w/w ratio showed the superior effect on the drug dissolution profile

Effect of oxyethylene chain length of the surfactant on the formation of microemulsion

A series of phase diagrams were established to determine the effect of the oxyethylene chain [OE] length of the surfactants on the formation of the microemulsion. Eumulgin B1 [12-OE], Eumulgin B2 [20-OE] and Eumulgin B3 [30-OE] were selected as surfactants in this study. The cloud point of the surfactant increased with the increase of its oxyethylene chain length. Phase studies have indicated that the configuration of the microemulsion depends on the length of OE chain, while the order of addition of the ingredients has only significant effect in case of Eumulgin B3