PHARMACEUTICAL APPLICATIONS OF DYNAMIC-MECHANICAL THERMAL-ANALYSIS

Dynamic mechanical thermal analysis (DMTA) is an analytical technique which involves the measurement of the rheological properties of a samp le over a range of temperatures. The theoretical and practical princip les of the technique are outlined, including a description of dynamic mechanical measurements and the types of measuring mode currently avai lable. A series of examples are given in which DMTA has been used to c haracterise the rheological properties and glass transition behaviour of materials of pharmaceutical interest. These include synthetic polym eric samples such as film coats, gels such as pectin-water systems, po lysaccharides such as hydroxypropyl methylcellulose and proteinaceous materials such as elastin. A discussion of how the technique could be used in the future to characterise pharmaceutical samples is given.