Abstract:
The objective of this study was to prepare and characterize swellable microspheres of
Ranolazine giving sustained release for chronic stable angina. Swellable microspheres
were prepared by spray drying method using HPMC (K15 and K100) and carbopol
934P as polymers to achieve sustained drug release. Effect of HPMC concentration,
drug: polymer ratio and carbopol concentration on physical properties of
microspheres were investigated. Optimization of different process parameters of the
spray dryer was performed. The optimization of microspheres was done based on the
entrapment efficiency & release rate. Microspheres were characterized in terms of
production yield, drug content, entrapment efficiency, particle size, SEM and
dissolution studies. Formulation containing 300 mg Carbopol 934P and 700 mg
HPMC K15 was found to be optimum formulation. The % yield, % entrapment
efficiency, % drug content, swelling index, in-vitro drug release (in 10 hrs) and
particle size were found to be 32.11%, 84.83%, 89.73%, 1.62, 90.7% and 20.41 μm
respectively gave the best results. Optimized formulation followed Hixon Crowell,
Korsmeyer- Peppas and zero order models, which indicates that the drug release followed erosion, swelling and sustained release mechanism. Stability studies at
400C±20C / 75 ± 5 % RH revealed that there was no significant change in appearance
and drug content, after 1 month. So, prepared formulation can be considered as stable
formulation. Hence, it can be concluded that the developed swellable microspheres
can be effectively used for oral administration in case of chronic stable angina.
