Silymarin, a phyto-constituent derived from the plant Silybum marianum, has been widely acknowledged for its hepatoprotective activities. Nevertheless, its clinical utility is adversely hampered by its poor water-solubility and its limited oral bioavailability. The aim of this study was to investigate the efficacy of phospholipid-based phytosomes for enhancing the oral bioavailability of silymarin. The phytosomes were prepared using the solvent evaporation technique and were optimized using a full factorial design. The optimized silymarin phytosomal formulation was then characterized for particle size, surface morphology, aqueous solubility, and in vitro drug release. Furthermore, in vivo antioxidant activity, hepatoprotective activity and oral bioavailability of the optimized formula were investigated in a rat model. The prepared silymarin phytosomes were discrete particles with a porous, nearly smooth surface and were 218.4 ± 2.54 nm in diameter. In addition, the optimized silymarin phytosomal formulation showed a significant improvement in aqueous solubility (~360 µg/mL) compared to pure silymarin and manifested a higher rate and extent of silymarin release from the optimized formula in dissolution studies. The in vivo assessment studies revealed that the optimized silymarin phytosomal formulation efficiently exerted a hepatoprotective effect in a CCl₄-induced hepatotoxicity rat model via restoring the normal levels of antioxidant enzymes and ameliorating cellular abnormalities caused by CCl₄-intoxication. Most notably, as compared to pure silymarin, the optimized silymarin phytosomal formulation significantly improved silymarin oral bioavailability, as indicated by a 6-fold increase in the systemic bioavailability. Collectively, phytosomes might represent a plausible phospholipid-based nanocarrier for improving the oral bioavailability of phyto-constituents with poor aqueous solubility.

Glaucoma is a progressive optic neuropathy characterized by a rise in the intraocular pressure (IOP) leading to optic nerve damage. Bimatoprost is a prostaglandin analogue used to reduce the elevated IOP in patients with glaucoma. The currently available dosage forms for Bimatoprost suffer from relatively low ocular bioavailability. The objective of this study was to fabricate and optimize solid lipid nanoparticles (SLNs) containing Bimatoprost for ocular administration for the management of glaucoma. Bimatoprost-loaded SLNs were fabricated by solvent evaporation/ultrasonication technique. Glyceryl Monostearate (GMS) was adopted as solid lipid and poloxamer 407 as surfactant. Optimization of SLNs was conducted by central composite design. The optimized formulation was assessed for average particle size, entrapment efficiency (%), zeta potential, surface morphology, drug release study, sterility test, isotonicity test, Hen’s egg test-chorioallantoic membrane (HET-CAM) test and histopathology studies. The optimized Bimatoprost-loaded SLNs formulation had an average size of 183.3 ± 13.3 nm, zeta potential of −9.96 ± 1.2 mV, and encapsulation efficiency percentage of 71.8 ± 1.1%. Transmission electron microscopy (TEM) study revealed the nearly smooth surface of formulated particles with a nano-scale size range. In addition, SLNs significantly sustained Bimatoprost release for up to 12 h, compared to free drug (p < 005). Most importantly, HET-CAM test nullified the irritancy of the formulation was verified its tolerability upon ocular use, as manifested by a significant reduction in mean irritation score, compared to positive control (1% sodium dodecyl sulfate; p < 0.001). Histopathology study inferred the absence of any signs of cornea tissue damage upon treatment with Bimatoprost optimized formulation. Collectively, it was concluded that SLNs might represent a viable vehicle for enhancing the corneal permeation and ocular bioavailability of Bimatoprost for the management of glaucoma.

Topical treatments are a potential therapeutic option for the therapy of osteoarthritis, with significant data supporting the effectiveness and safety of topical formulation. Topical gel formulations may offer an alternative to oral formulations to relieve osteoarthritis (OA) pain while decreasing systemic exposure. Topical capsaicin transemulgel may represent an effective and safe alternative. The transemulgel was prepared from aqueous Aloe vera gel and Carbopol 934 with capsaicin in clove oil emulsion. The optimized transemulgel of capsaicin showed a pH of 6.1 ± 0.1 and viscosity of 15263–998 cps. Data from in vitro diffusion demonstrated improved permeability properties. The formulation caused no skin irritation when applied topically. The optimal transemulgel spreadability was found to be 20.23 g·cm/s. In vitro and ex vivo studies of the optimized formulation were performed. The skin irritant test was performed on rat skin with an optimized and marketed formulation. Both showed no irritation on the skin. The transemulgel of the capsaicin with Aloe vera gel was proven to be effective for osteoarthritis therapy.

The present study was aimed of design and evaluation of bigel containing flurbiprofen. Bigels are interesting innovative two phase systems that have been recently proposed as structured system for delivery of active ingredients. They possess the advantages of both hydrogel and organogel. Organogel was prepared by pluronic lecithin and hydrogel was prepared using HPMC. Bigels were prepared by mixing of organogel and hydrogel in appropriate ratio. Organogel and hydrogel was evaluated for pH, viscosity, extrudability and spreadabilty. Formulation F3 from organogel and formulation H3 from hydrogel was selected as optimized formulations and was used for the preparation of bigel. The prepared bigel was evaluated for pH, viscosity, extrudability, spread ability, in vitro drug release studies, ex vivo permeation studies, stability studies and skin irritation test. All formulations of bigel showed extended release out of which formulation B3 was selected as the optimized formulation on the basis of evaluation parameters. In vitro permeation release was found to be 89.99% at the end of 8 hrs. The release kinetics of flurbiprofen bigel followed Higuchi model. The bigels were found to be stable and skin irritation studies on Wistar rats showed that the prepared bigels were compatible. Based on the encouraging results bigels containing flurbiprofen can be used as extended release system.

Sulconazole is a broad spectrum antifungal agent of the imidazole class used against dermatophytes and other fungi to treat skin infections. The aim of the present work was to formulate and evaluate a microemulsion-based topical sulconazole gel. Microemulsion formulation of sulconazole nitrate was prepared by using oil, surfactant, cosurfactant and water at different ratios. This was then subjected to clarity and particle size analysis, a centrifugation test, a dilution test, and freeze thawing. The zeta potential of formulation F1 was -41.3 and stable. The pH of the microemulsion formulation was within the range of pH of skin. F1 showed a higher percentage amount of drug as compared with the other formulations. The viscosity showed that F1 was optimum. The freezing and thawing results showed there was no phase separation and the formulation was stable. In vitro drug release showed that the drug release from the microemulsion of F1 was higher when compared to the other formulations. It revealed F1 had the highest drug content of 95.88±0.3% and % cumulative drug release was 88.75% release in 8 h. The in vivo skin irritation study on rats confirmed that formulation was nontoxic and nonirritant. The present study confirmed the safety of the formulated sulconazole loaded microemulsion gel for topical application.