IIT Bombay is one of the leading institutions in the country for research in the area of Nanotechnology. IIT Bombay has recently consolidated its Nanotechnology research activities through the formation of a Centre for Research in Nanotechnology & Science (CRNTS). The formation of this centre has been made possible through a generous grant from the Department of Science & Technology (DST), Govt. of India
       A9: Aerosol routes for pulmonary delivery and the synthesis of drug nanoparticles
       Efficient pulmonary drug delivery depends upon engineering drug nano-particles which are non-toxic, stable on nebulization, and deposit efficiently in the pulmonary lung. We are investigating drug encapsulation in liposomes for pulmonary delivery. We will also investigate aerosol routes for the production of drug nanoparticles.
       Themes: * Factors affecting liposome / micelle rupture during aerosolization. * Production of mono-disperse drug nano-particles through ultrasonic nebulization and electro-spray techniques. * Enhanced pulmonary delivery of vaccines.
       Approaches:
       * Laboratory production of micelle / liposome encapsulated drugs.
       * Determination of aerodynamic deposition characteristics through laser scattering, inertial impaction and time-of-flight techniques.
       * Characterization of structure using TEM / cryo-TEM.
       * Leakage studies of small and large fluorescent protein molecules from vesicle envelopes.
       Delivery into the pulmonary or alveolar lung is efficient through sedimentation for larger particles that escape deposition in the upper airways or through diffusion for particles of the order of 20 nm diameter. Encapsulation using polymers results in potential problems for repeated delivery applications like insulin, from build-up in the lung of polymer, of unknown toxicity.
       Liposomes as drug encapsulating envelopes offer the advantages of biocompatibility with the lung surfactant and of easy production and loading of drugs.
       Potential drug nanoparticle synthesis methods through aerosol routes include: (i) gas-to-particle conversion, (ii) droplet-to-particle conversion, (iii) contacting of solution droplets with antisolvents, and (iv) photopolymerization of droplets. Currently, there are a number of techniques available for generation of highly mondisperse droplets in the few nanometers (e.g., electrospray) to a few hundred micrometers (e.g., vibrating orifice aerosol generators) size range, and these droplets can potentially be used for production of pharmaceutical nanoparticles using the methods (ii) through (iv). We will focus on the following:
       * Factors affecting liposome / vesicle rupture during aerosolization.
       * Production of mono-disperse drug nano-particles in aerosol droplets using ultrasonic nebulization or electrospray techniques, in combination with droplet evaporation and reaction-coagulation mechanisms.