Application of Spray Drying Technique for Flowability enhancement of Divalproex Sodium.

BACKGROUND

Tablets and capsules are the most accepted and widely used solid dosage forms in the medical therapy. Flow property of the powders is playing a key role in the various pharmaceutical fields especially in the fomulation of tablets and capsules. The high hygroscopic crystalline structure of anhydrous Divalproex sodium (DVX) makes it to be appear as waxy white flakes with almost no powder flowability which cause serious problems during the tabletting and capsule filling procedures.

PURPOSE

The main objective of this study was to improve the flowability of DVX powder.

METHODS

DVX was mixed with mannitol or lactos in different ratios, dissolved in water and differet binary mixtures of ethanol:water, and finally spray dried with different spray drying conditions. Particle size and powders morphology were assessed by Scanning Electron Microscopy (SEM). The poweder flowability was assessed by measurmet of Hausner ratio (HR), Carr's index (CI) and angle of repose (AOR) indexes. Furthermore, the content uniformity of DVX in spray-dried powders was determined by using a validated HPLC technique.

RESULTS

The results showed that spray drying technique improved DVX flowability by forming spherical particles with narrow size distribution AOR value of DVX was decrease from not flowable to 36.1° in spray dried solid dispersion indicating the improvmet of powder flowability from very poor to fair/good condition.

CONCLUSION

Findings suggest that the spray drying technique improves DVX flowability and may pave the way for improvement in the tabletting procedure of DVX.