Khalid Anwer

Proniosomal transdermal therapeutic system of losartan potassium: development and pharmacokinetic evaluation

The purpose of the current study was to investigate the feasibility of proniosomes as transdermal drug delivery system for losartan potassium. Different preparations of proniosomes were fabricated using different nonionic surfactants, such as Span 20, Span 40, Span 60, Span 80, Tween 20, Tween 40, and Tween 80. Different formulae were prepared and coded as PNG-1 (proniosomal gel-1) to PNG-7. The best in vitro skin permeation profile was obtained with proniosomal formulation PNG-2 in 24 h. The permeability parameters such as flux, permeability coefficient, and enhancement ratio were significant for PNG-2 compared with other formulations (P < 0.05). This optimized PNG-2 was fabricated in the form of transdermal patch using HPMC gel as a suitable base. Proniosomal transdermal therapeutic system (PNP-H) was found to be the optimized one as it gave better release of drug and better permeation in a steady-state manner over a desired period of time, that is, 24 h through rat skin. In vivo pharmacokinetic study of PNP-H showed a significant increase in bioavailability (1.93 times) compared with oral formulation of losartan potassium. The formulation appeared to be stable when stored at room temperature (30 ± 2°C) and at refrigeration temperature (4 ± 2°C) for 45 days.

Dissolution thermodynamics and solubility of silymarin in PEG 400-water mixtures at different temperatures

Abstract An isothermal method was used to measure the solubility of silymarin in binary polyethylene glycol 400 (PEG 400) + water co-solvent mixtures at temperatures T = 298.15–333.15 K and pressure p = 0.1 MPa. Apelblat and Yalkowsky models were used to correlate experimental solubility data. The mole fraction solubility of silymarin was found to increase with increasing the temperature and mass fraction of PEG 400 in co-solvent mixtures. The root mean square deviations were observed in the range of 0.48–5.32% and 1.50–9.65% for the Apelblat equation and Yalkowsky model, respectively. The highest and lowest mole fraction solubility of silymarin was observed in pure PEG 400 (0.243 at 298.15 K) and water (1.46 × 10−5 at 298.15 K). Finally, thermodynamic parameters were determined by Van’t Hoff and Krug analysis, which indicated an endothermic and spontaneous dissolution of silymarin in all co-solvent mixtures.

Wound Healing Study of Eucalyptus Essential Oil Containing Nanoemulsion in Rat Model

The objective of this investigation was to develop nanoemulsion formulations of Eucalyptus essential oil (EEO) and to evaluate its wound healing effects in comparison with standard gentamycin in rat model. Various nanoemulsionns of EEO were prepared using aqueous phase titration method and the zones of nanoemulsion were identified by the construction of phase diagrams. EEO nanoemulsions were investigated in terms of physical stability, self-nanoemulsification efficiency and physicochemical characterization. Optimized nanoemulsion of EEO was selected for wound healing study, collagen estimation and histopathological evaluation in rats in comparison with pure EEO and standard gentamycin. Optimized nanoemulsion presented significant would healing activity in rats as compared with pure EEO upon oral administration. The wound healing activity of optimized nanoemulsion was comparable with standard gentamycin. Optimized EEO nanoemulsion also presented significant enhancement in collagen content as compared with pure EEO and negative control. However, the collagen contents of optimized nanoemulsion treated animals were comparable with standard gentamycin-treated animals. Histopathological studies of optimized nanoemulsion treated rats showed no signs of inflammatory cells which suggested the safety and non-toxicity of EEO nanoemulsion. This study suggested the potential of nanoemulsion in enhancing the wound healing activity of EEO upon oral administration.