Abstract. The aim of the present study was to enhance the dissolution rate of meloxicam (MLX), a practically water-insoluble drug by preparation of solid dispersion using a hydrophilic polymer, poloxamer 188 (PXM). The kneading technique was used to prepare solid dispersions. A 3 2 full factorial design approach was used for optimization wherein the drug, polymer ratio (X 1 ), and the kneading time (X 2 ) were selected as independent variables and the dissolution efficiency at 60 min (%DE 60 ) and yield percent were selected as the dependent variable. Multiple linear regression analysis revealed that for obtaining higher dissolution of MLX from PXM solid dispersions, a high level of X 1 and a high level of X 2 were suitable. The use of a factorial design approach helped in optimization of the preparation and formulation of solid dispersion. The optimized formula was characterized by solubility studies, angle of repose, and contact angle; Fourier transform infrared spectroscopy, differential scanning calorimetry, x-ray diffraction studies, and scanning electron microscopy demonstrated that enhanced dissolution of MLX from solid dispersion might be due to a decrease in the crystallinity of MLX and PXM. Analysis of dissolution data of optimized formula indicated the best fitting with KorsemeyerPeppas model and the drug release kinetics as Fickian diffusion. In conclusion, dissolution enhancement of MLX was obtained by preparing its solid dispersion with PXM using kneading technique.

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Purpose: To investigate the effect of various surfactants and cosurfactants, and their ratio on microemulsions prepared with isopropyl palmitate (IPP)Methods: Tween 20, 40, 60, and 80 were used separately as surfactant with methanol, ethanol,

Abstract. Diazepam is one of the most prescribed benzodiazepines. The purpose of the present research was to optimize the formulation of orodispersible tablets of diazepam. Orodispersible tablets of diazepam were prepared using different types of superdisintegrants (Ac-Di-Sol, sodium starch glycolate, and crospovidone (CP)) and different types of subliming agents (camphor and ammonium bicarbonate (AB)) at different concentrations and two methods of tablets preparations (wet granulation and direct compression methods). The formulations were evaluated for flow properties, wetting time, hardness, friability, content uniformity, in vivo disintegration time (DT), release profiles, and buccal absorption tests. All formulations showed satisfactory mechanical strength except formula F5 which contains camphor and formula F9 which is prepared by direct compression method. The results revealed that the tablets containing CP as a superdisintegrant have good dissolution profile with shortest DT. The optimized formula F7 is prepared using 10% CP as a superdisintegrant and 20% AB as a subliming agent by wet granulation method which shows the shortest DT and good dissolution profile with acceptable stability. This study helps in revealing the effect of formulation processing variables on tablet properties. It can be concluded that the orodispersible tablets of diazepam with better biopharmaceutical properties than conventional tablets could be obtained using formula F7.

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Nanoemulsions (NE) are isotropic, dispersions of oil, water, surfactant(s) and cosurfactant(s). A range of components (11 surfactants, nine cosurfactants, and five oils) were investigated as potential excipients for preparation of ketorolac tromethamine (KT) ocular nanoemulsion. Diol cosurfactants were investigated for the effect of their carbon chain length and dielectric constant (DEC), Log P, and HLB on saturation solubility of KT. Hen’s Egg Test—ChorioAllantoic Membrane (HET-CAM) assay was used to evaluate conjunctival irritation of selected excipients. Of the investigated surfactants, Tween 60 achieved the highest KT solubility (9.89 ± 0.17 mg/mL), followed by Cremophor RH 40 (9.00 ± 0.21 mg/mL); amongst cosurfactants of interest ethylene glycol yielded the highest KT solubility (36.84 ± 0.40 mg/mL), followed by propylene glycol (26.23 ± 0.82 mg/mL). The solubility of KT in cosurfactants was affected by four molecular descriptors: carbon chain length, DEC, log P and HLB. KT solubility was directly proportional to DEC and the HLB yet, inversely proportional to carbon chain length and log P. All surfactants, except Labrasol ALF, were non-irritant. The majority of cosurfactants were slightly irritant, butylene glycol was a moderate irritant, pentylene and hexylene glycols were strong irritants. These findings will inform experiments aimed at developing NE formulations for ocular administration of KT.

Background and purpose: Microemulsions are gaining an increased interest in transdermal drug delivery. Microemulsions are stable, easy to prepare, and provide high solubilizing capacity for various drugs. The aim of this work was to prepare microemulsions from jojoba oil for transdermal delivery of ketorolac and lidocaine HCl with improved permeation. Experimental approach: Microemulsions based on jojoba oil as the oil phase were formulated for transdermal delivery of lidocaine HCl and ketorolac. Brij 97 was selected as surfactant and hexanol as cosurfactant. Pseudoternary phase diagrams were constructed. Selected microemulsion formulations were characterized for their physical properties and in vitro drug permeation. Findings/Results: Water-in-oil microemulsions were obtained with droplet sizes not more than 220 nm. The viscosity of the microemulsions was linked to the viscosity of the surfactant used. Improved drug permeation rates were observed for both model drugs. The significant increase in permeation rate in presence of hexanol was due to its impact on skin integrity as indicated by the histopathological study. Drug permeation enhancements were caused by the surfactant, the cosurfactant used, jojoba oil itself, and the microemulsion formulation. Higher surfactant content showed lower lag times and better flux. Conclusion and implications: Jojoba oil microemulsions are considered promising vehicles for transdermal delivery of ketorolac and lidocaine HCl with improved drug permeation. Jojoba oil-based microemulsion would present a safe and effective means for delivering drugs through the skin.

The present investigation was undertaken with the objective of developing fast dissolving film(s) of a tricyclic antidepressant drug amitriptyline hydrochloride in order to improve its bioavailability, optimize its therapeutic action especially when used to treat major depression and to enhance the compliance for the developmentally disable, mentally ill, elderly and pediatric patients. , the study based on cross over design using experimental animals (rabbits). The pharmacokinetic results revealed that the fast dissolving films has higher peak blood concentration (C max , 0.927µg/ml) within shorter time (T max, 2 hours), indicating rapid absorption and faster onset of action with acceptable bioavailability value. These findings suggest that the fast dissolving film containing amitriptyline hydrochloride is expected to become one of choices for the treatment of acute depression.