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Reduced brominated derivative of noscapine (Red-Br-Nos, EM012), has potent anti-inflammatory property. However, physicochemical limitations of Red-Br-Nos like low aqueous solubility (0.43×10(-3) g/mL), high lipophilicity (logP∼2.94) and ionization at acidic pH greatly encumber the scale-up of oral drug delivery systems for the management of colitis. Therefore, in present investigation, chitosan microspheres bearing Red-Br-Nos (CTS-MS-Red-Br-Nos) were prepared by emulsion polymerization method and later coated with wheat germ agglutinin (WGA-CTS-MS-Red-Br-Nos) to boost the bioadhesive property. The mean particle size and zeta-potential of CTS-MS-Red-Br-Nos were measured to be 10.5±5.4 μm and 8.1±2.2 mV, significantly (P<0.05) lesser than, 30.2±3.2 μm and 19.2±2.3 mV of WGA-CTS-MS-Red-Br-Nos. Furthermore, various spectral techniques like SEM, FT-IR, DSC and PXRD substantiated that Red-Br-Nos was molecularly dispersed in tailored microspheres in amorphous state. Surface bioadhesive property of WGA-CTS-MS-Red-Br-Nos promoted the affinity toward colon mucin cells in simulated colonic fluid (SCF, pH∼7.2). In vitro release studies carried out on WGA-CTS-MS-Red-Br-Nos and CTS-MS-Red-Br-Nos indicated that SCF with colitis milieu (pH∼4.7) favored the controlled release of Red-Br-Nos, owing to solubilization at acidic pH. Consistently, in vivo investigation also demonstrated the utility of WGA-CTS-MS-Red-Br-Nos, which remarkably attenuated the DSS encouraged neutrophil infiltration, myeloperoxidase activity, and pro-inflammatory cytokine production in C57BL6J mice, as compared to CTS-MS-Red-Br-Nos and Red-Br-Nos suspension. The noteworthy anti-inflammatory activity of WGA-CTS-MS-Red-Br-Nos against acute colitis may be attributed to enhanced drug delivery, affinity and utmost drug exposure at inflamed mucosal layers of colon. In conclusion, WGA-CTS-MS-Red-Br-Nos warrants further in-depth in vitro and in vivo investigations to scale-up the technology for clinical translation., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Liposomes have been widely investigated since 1970 as drug carriers for improving the delivery of therapeutic agents to specific sites in the body. As a result, numerous improvements have been made, thus making this technology potentially useful for the treatment of certain diseases in the clinics. The success of liposomes as drug carriers has been reflected in a number of liposome-based formulations, which are commercially available or are currently undergoing clinical trials. The current pharmaceutical preparations of liposome-based therapeutic systems mainly result from our understanding of lipid-drug interactions and liposome disposition mechanisms. The insight gained from clinical use of liposome drug delivery systems can now be integrated to design liposomes that can be targeted on tissues, cells or intracellular compartments with or without expression of target recognition molecules on liposome membranes. This review is mainly focused on the diseases that have attracted most attention with respect to liposomal drug delivery and have therefore yielded most progress, namely cancer, antibacterial and antifungal disorders. In addition, increased gene transfer efficiencies could be obtained by appropriate selection of the gene transfer vector and mode of delivery.

Purpose: Tamoxifen, an anti-estrogen compound, has recently been figured as a useful agent in the treatment of certain skin specific disorders. This recent found application has generated an interest in its topical formulation in order to avoid the side effects associated with oral administration, while parenteral administration is restricted due to its limited aqueous solubility. Liposomal carriers, well known for their potential in topical drug delivery, have been chosen to help transport tamoxifen molecules in the skin layers. These vesicles are also expected to provide lipid enriched hydrating conditions to help retain the drug molecules within the dermal layers, at or near to the site of action. With this objective, tamoxifen loaded liposomal systems have been prepared and their topical performance has been compared with non-liposomal systems containing tamoxifen., Method: Multilamellar liposomes of tamoxifen were prepared by thin film hydration method. Various formulation ( viz. lipid composition, drug-lipid ratio, amount and type of surface charge imparting agent etc.) and process parameters (hydration temperature, hydration time etc.) were studied to obtain liposomes with desired attributes. Prepared liposomes were characterized for morphological and micromeritic attributes, employing Malvern mastersizer and optical microscopy. Stability of the liposomes in terms of their drug holding capacity was assessed for a period of 5 weeks, on storage under defined conditions. Liposomal formulations of tamoxifen were evaluated for in-vitro skin permeation, using mice skin. The results thus obtained were compared with that of aqueous solution and Carbopol gel, containing tamoxifen in equal amounts., Results: Optimized process and formulation parameters resulted in multilameller, homogenous population of liposomes in the size range of 1 to 13 mm (mean vesicle diameter 5.3 microm), exhibiting normal size distribution. Maximum loading of tamoxifen was noted to be 57.5% (38.3 mu g of drug per mg of lipids), for liposomes composed of hydrogenated phosphatidylcholine and cholesterol, employing 66.6 microg drug per mg of lipids during preparation. Incorporation of dicetylphosphate or stearylamine as charge imparting agent did not influence the vesicular entrapment of TAM in a favorable manner. Amongst different storage conditions, the liposomes stored at 2 to 8 degrees C were found to be most stable, with only 5% drug loss over the storage period of 5 weeks. Significantly higher skin permeation of tamoxifen from liposomal formulations (flux values 63.67 microg/cm2/h and 59.87 microg/cm2/h for liposomal suspension and liposomal gel) has been achieved, as compared to solution (21.65 microg/cm2/h) and Carbopol gel (24.55 microg/cm2/h) containing tamoxifen. Higher magnitude of tamoxifen retention in the skin layers was noted with liposomal formulations vis-à-vis non-liposomal formulations of the drug., Conclusion: Tamoxifen molecules could be successfully entrapped in the liposomes with reasonable drug-loading and desired vesicle specific characters. Higher rate of drug transfer across the skin with liposomal formulations of tamoxifen, suggests that the drug in its lipo-solubilised state might have found facilitated entry into the tough barrier consisting of stratum corneum. The phospholipid enriched amphiphillic nature of the vesicles can be held responsible for modifying the properties of the keratinised layer. Integration of phospholipid molecules with the skin lipids might have served further, to help retain the drug molecules within the skin, thus leading to prolonged presence of drug molecules at the receptor site. These findings have been seen to support the improved and localized drug action in the skin, thus providing a better option to deal with skin-cited problems.

The aim of the present study was to encage a drug into liposomal structures to make them more effective, safe and targeted to liver cells. The investigation deals with critical parameters controlling the formulation and evaluation of silibinin (silymarin, CAS22888-70-6) liposomes. Small unilamellar liposmal vesicles were prepared using the ethanol injection method. The various formulation and process variables were optimized to improve the drug entrapment efficiency. The study includes the selection of lipid composition, impact of charge imparting agent and the nature of hydration medium. The stability and size parameters were critically monitored. The liposomal systems were also studied for hepatoprotective activity in mice against carbon tetrachloride induced hepatotoxicity and gastroprotective activity using the pyloric ligation method. The results indicate a significant effect of cholesterol on drug-entrapment and drug-leakage characteristics. The size distribution range was from 0.056-1.270 microns with the most frequent size ranging from 0.266-0.466 micron. The amount of drug loaded in these vesicles was approx. 90%. Lipid cholesterol mass ratio of 10:2 has a maximum entrapment of 87.2% (+/- 1.77). The results obtained from the in vivo studies indicate the improved performance of silymarin in liposomes at a level of 55.6% hepatoprotection in comparison to 33.08% of plain drug. Plain liposomes showed hepatoprotection though to a lower degree of 24.2%. Liposomal silymarin and plain liposomes also showed significant antiulcer activity as compared with plain silymarin and control groups.

We have prepared a novel, aqueous gel-based, liposome-entrapped formulation of dithranol. Herein, we report preliminary observations on its efficacy, tolerability, and cosmetic acceptability in treating stable plaque psoriasis. Nineteen plaques of psoriasis in nine adult patients were treated for six weeks in a prospective, open-label trial. In five patients, there was total clearance of lesions, with more than 50% subsidence in a further two patients. Significantly, there were no reports of lesional or perilesional irritation, and only one patient showed faint brown staining of the skin, which was completely and rapidly reversible. These preliminary results indicate that our liposomal dithranol gel has potential advantages over presently available preparations of dithranol; these may translate into enhanced acceptance of this useful drug by patients and physicians.