SUPERCRITICAL FLUID TECHNOLOGY: NASCENT CONTRIVANCE FOR PHARMACEUTICAL PRODUCT DEVELOPMENTAbstract
A supercritical fluid (SF) can be defined as a dense non condensable fluid. A fluid reaches the supercritical status when its temperature and pressure exceed the relevant critical temperature and pressure. At the critical point only a single phase exists which has some properties typical of liquids (density) and some of gases (viscosity, compressibility, and mass diffusion coefficient). For pharmaceutical applications, the most widely used SF is carbon dioxide (more than 98% of the applications have been developed using this fluid) because of its low and easily accessible critical temperature (31.2◦C) and pressure (7.4MPa), non-flammability, non-toxicity and inexpensiveness. The physical and thermal properties of SCFs fall between those of the pure liquid and gas. SCFs offer liquid-like densities, gas-like viscosities, gas-like compressibility properties and higher diffusivities than liquids. The properties of SCFs, such as polarity, viscosity, and diffusivity, can be altered several-fold by varying the operating temperature and/or pressure during the process. This flexibility is enabling the use of SCFs for various applications in the food and pharmaceutical industries, with the drug delivery system design being a more recent addition.
B.S. Wakure*, A.V. Yadav , N.M. Bhatia and M.A. Salunke
Vilasrao Deshmukh Foundation, Group of Institutions, VDF School of Pharmacy , Latur-413 531, Maharashtra, India
17 February, 2012
27 April, 2012
13 June, 2012
01 July, 2012