DESIGN AND EVALUATION OF SELF-NANOEMULSIFYING DRUG DELIVERY SYSTEMS OF MANIDIPINE FOR ENHANCEMENT OF SOLUBILITY

Objective: The present work is aimed at developing liquid self-nanoemulsifying drug delivery system (liquid-SNEDDS) of manidipine. Methods: The manidipine SNEDDS is formulated with excipients comprising Capmul MCM as oil phase, Transcutol P as surfactant, and Lutrol L 300 as cosurfactant. The prepared fifteen formulations of manidipine SNEDDS were performed for emulsification time, percentage transmittance, particle size, drug release, in vitro dissolution and stability studies. Ternary phase diagram plotted using Chemix software. Results: The optimized manidipine liquid SNEDDS formulation (F14) subjected to drug-excipient compatibility studies by Fourier-transform infrared spectroscopy and characterized for particle size, zeta potential, scanning electron microscopy, and stability studies. The morphology of manidipine SNEDDS indicates spherical shape with uniform particle distribution. The percentage drug release from optimized formulation F14 (98.24±5.14%) was higher than that of pure drug (39.17±2.98%). The stability data indicated no noticeable change in drug content, emulsifying properties, drug release, and appearance. Conclusion: Hence, a potential SNEDDS formulation of manidipine developed with enhanced solubility, dissolution rate, and bioavailability

DEVELOPMENT AND IN VITRO EVALUATION OF SOLID DISPERSIONS OF CANDESARTAN CILEXETIL

Objective The main objective of the present study is systematic development of solid dispersions of Candesartan cilexetil by solvent evaporation method to enhance the solubility and bioavailability. Methods In the present study, eighteen formulations of solid dispersions were prepared with 1:1 and 1:3 ratios of drug: carrier and with and without surfactant. There was significant improvement in the rate of drug release from all 20 solid dispersions and the formulation (SD16) comprising Candesartan: containing Soluplus (1:3 ratio of drug:  Soluplus with 2% SLS as surfactant) by solvent evaporation process. Results Final optimized design SD16 contained maximum drug content of 99.08%. In in vitro dissolution studies it shows greater dissolution rate i.e. 99.7±4.2% associated through additional designs and pure drug. The drug was compatible with all the excipients as per FTIR (Fourier transform infrared spectroscopy). From powder X-ray diffraction (p-XRD) and by (SEM) studies it was evident that crystalline form of Candesartan has been converted into amorphous form within solid dispersion design.  Conclusion From these studies we can accomplish solid dispersions are one of the greatest favorable formulation for Candesartan cilexetil for enhancing the solubility and bioavailability of poorly water soluble drugs in the effective group of hypertension and other cardiac problems

Enantiomeric separation and determination of stereospecific drug release from marketed racemic omeprazole products by chiral HPLC

The objective of carrying out this research work was to investigate the effect of chirality on stereospecific dissolution of omeprazole enantiomers from various marketed racemic omeprazole products. Omeprazole is used for the treatment of gastro-duodenal ulcers and symptomatic gastro-oesophageal reflux. Dissolution of various marketed products was performed using USP type I apparatus in 0.1 N HCl for 2 h and in pH 6.8 phosphate buffer for 1 h at 100 rpm. The separation of enantiomers was done using a chiral HPLC method on CHIRAL AGP column (100 x 4.6 mm i.d.). The wavelength for UV detection was set at 210 nm. The mobile phase was 10 mM phosphate buffer with 5 % acetonitrile adjusted to pH 6.5 at a flow rate of 0.9 ml min-1 with an injector valve fitted to a 50 μL volume sample loop. The retention times for R and S enantiomers of omeprazole were 5 and 7.5 min, respectively. The dissolution of S enantiomer of Ocid-20 and Omee was found to be significantly more compared to their R enantiomer at 5 and 10 min dissolution time points after which there was no stereospecific discrimination in the dissolution. From the S/R ratios of different racemic omeprazole marketed products it was concluded that at 5 and 10 min dissolution time points there was a stereospecific drug release between the S and R enantiomers with the brands Ocid-20 and Omee (p 0.05).Colegio de Farmacéuticos de la Provincia de Buenos Aire

PREPARATION AND IN VIVO EVALUATION OF CANDESARTAN CILEXETIL SOLID DISPERSIONS

Objective: The present study aims at development of solid dispersions (SD) of candesartan cilexetil for enhanced solubility and bioavailability. Methods: About 18 SD formulations of candesartan cilexetil were prepared by solvent evaporation technique and evaluated. The in vitro release studies were conducted and the best formulation chosen was further characterized for Fourier transform infrared spectroscopy, Scanning electron microscope, X-ray, and stability. The in vivo evaluation study conducted in rats. Results: The formulation SD16 containing drug and Soluplus in 1:3 ratio along with 2% selective laser sintering was chosen optimal based on drug content (99.08%), and drug release (99.7%). In vivo studies conducted on SD16 showed that mean time to peak concentration (Tmax) was 2.0±0.05 and 4±0.2 h for the optimized and pure drug, respectively, while mean maximum drug concentration (Cmax) was 570.63±2.65 ng/mL and was significant as compared to the candesartan pure drug 175.146±0.07 ng/mL. Area under curve AUC0-∞ infinity for candesartan SD16 was higher (4860.61±1.05 ng.h/ml) than pure drug suspension 1480±1.72 ng.h/ml. Conclusion: Hence, the developed SD formulations enhanced the bioavailability of drug by 3 folds