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Dry powder inhalers (DPI) are generally formulated by mixing micronized drug particles with coarse lactose carrier particles to assist powder handling during the manufacturing and powder aerosol delivery during patient use.In the present study, surface modified lactose (SML) particles were produced using force control agents, and their in vitro performance on dry powder inhaler (DPI) formulation of Fluticasone propionate was studied. With a view to reduce surface passivation of high surface free energy sites on the most commonly used DPI carrier, α- lactose monohydrate, effects of various force control agents such as Pluronic F-68, Cremophor RH 40, glyceryl monostearate, polyethylene glycol 6000, magnesium stearate, and soya lecithin were studied.DPI formulations prepared with SML showed improved flow properties, and atomic force microscopy (AFM) studies revealed decrease in surface roughness. The DSC and X-ray diffraction patterns of SML showed no change in the crystal structure and thermal behavior under the experimental conditions. The fine particle fraction (FPF) values of lactose modified with Pluronic F-68, Cremophor RH 40, glyceryl monostearate were improved, with increase in concentration up to 0.5%. Soya lecithin and PEG 6000 modified lactose showed decrease in FPF value with increase in concentration. Increase in FPF value was observed with increasing concentration of magnesium stearate. Two different DPI devices, Rotahaler(®) and Diskhaler(®), were compared to evaluate the performance of SML formulations. FPF value of all SML formulations were higher using both devices as compared to the same formulations prepared using untreated lactose. One month stability of SML formulations at 40°C/75% RH, in permeable polystyrene tubes did not reveal any significant changes in FPF values.SML particles can help in reducing product development hindrances and improve inhalational properties of DPI.

Cisplatin, a platinum compound, exerts its cytotoxic effects by coordinating to DNA where it inhibits both replication and transcription, and induces programmed cell death. It is used in the treatment of non-small cell lung cancer. In the present study, an attempt was made to achieve better treatment of lung cancer by direct lung delivery of cisplatin microparticulate systems, which helps to localize the drug in the lungs, and also provide sustained action. Cisplatin-loaded chitosan microspheres were prepared by emulsification and ionotropic gelation method, and characterized for drug content, particle size, densities, flow properties, moisture content, and surface topography by SEM and in vitro drug release was evaluated in simulated lung fluid at 37° at pH 7.4. The respirable or fine particle fraction (FPF) was determined by using twin stage impinger (TSI). Further stability evaluation of cisplatin-loaded DPI systems was carried out at 25°/60% RH and at 40°/75% RH.

Etoposide is a semisynthetic compound, widely used in treatment of non small cell lung cancer. However, frequent dosing and adverse effects remain a major concern in the use of etoposide. Liposomal systems for pulmonary drug delivery have been particularly attractive because of their compatibility with lung surfactant components. In the present investigation, pulmonary liposomal delivery system of etoposide was prepared by film hydration method. Various parameters were optimized with respect to entrapment efficiency as well as particle size of etoposide liposomes. For better shelf life of etoposide liposomes, freeze drying using trehalose as cryoprotectant was carried out. The liposomes were characterized for entrapment efficiency, particle size, surface topography, and in vitro drug release was carried out in simulated lung fluid at 37° at pH 7.4. The respirable or fine particle fraction was determined by using twin stage impinger. The stability study of freeze dried as well as aqueous liposomal systems was carried out at 2-8° and at ambient temperature (28±4°). The freeze dried liposomes showed better fine particle fraction and drug content over the period of six months at ambient as well as at 2-8° storage condition compared to aqueous dispersion of liposomes.