Liposomal formulations of Etoposide and Docetaxel for p53 mediated enhanced cytotoxicity in lung cancer cell lines.

The objective of present investigation was to develop and assess comparative enhancement in cytotoxicity of liposomal Etoposide and Docetaxel in non-small cell lung cancer cell lines after pre-treatment and co-administration of p53 tumor suppressor gene and to assess direct lung targeting of optimized formulations by dry powder inhaler technology. Cationic liposomes with and without drug were prepared and allowed to form p53-lipoplex for undertaking cytotoxicity studies in H-1299 (p53 null) and A-549 (p53 wt) cell lines. The optimized lipoplexes showed average size of 200-350 nm, zeta potential of 25-32 mV and sustained drug release up to 16-24 h.

Gemini amphiphiles: a novel class of nonviral gene delivery vectors.

A number of carriers have been developed for the delivery of genes, but the search for a clinically successful ideal carrier is ongoing. Nonviral carriers, especially cationic liposomes, were developed to resolve issues related to the immunogenicity and oncogenicity of viral carriers. Many synthetic cationic amphiphiles have been synthesized and structurally modified to incorporate genes into vesicular carriers to enhance DNA transfection efficiency and to reduce carrier toxicity.

Recent advances in liposomal dry powder formulations: preparation and evaluation.

Liposomal drug dry powder formulations have shown many promising features for pulmonary drug administration, such as selective localization of drug within the lung, controlled drug release, reduced local and systemic toxicities, propellant-free nature, patient compliance, high dose carrying capacity, stability and patent protection. Critical review of the recent developments will provide a balanced view on benefits of liposomal encapsulation while developing dry powder formulations and will help researchers to update themselves and focus their research in more relevant areas. In liposomal dry powder formulations (LDPF), drug encapsulated liposomes are homogenized, dispersed into the carrier and converted into dry powder form by using freeze drying, spray drying and spray freeze drying.

Recent patents review on intranasal administration for CNS drug delivery.

The treatment of brain disorders is the greatest challenge because of a variety of formidable obstacles in effective drug delivery and maintaining therapeutic concentrations in the brain for a prolonged period. The brain is a delicate organ, and evolution built very efficient ways to protect it. The same mechanisms that protect it against intrusive chemicals can also frustrate therapeutic interventions.

Development of dry powder inhalers.

Development of dry powder inhalers involves powder recrystallization, formulation, dispersion, delivery, and deposition of the therapeutic agent in different regions of the airways in prophylaxis/ treatment/ diagnosis of pulmonary and systemic disorders. Conventional powder production by crystallization and milling has many limitations resulting into development of alternative techniques to overcome the problems. In the last decade many patents have been filed claiming improvement in aerosol performance of dry powder inhalers through the use of (i) incorporation of fines of carrier particles to occupy active sites on the surface and use of hydrophobic carriers to facilitate deaggregation through reduced surface energy and particle interaction (ii) reducing aerodynamic diameters through particle engineering and incorporating drug into porous or low particle density, and/or (iii) preparing less cohesive and adhesive particles through corrugated surfaces, low bulk density, reduced surface energy and particle interaction and hydrophobic additives.