The influence of derivatives of acrylic acid (PAA), Carbopol 907, 941, 934 and 940, and hydroxypropyl methylcellulose (HPMC) on metoclopramide release from bioadhesive tablets designed for buccal use has been studied. Both the PAA/HPMC ratio and the molecular weight of the Carbopol gave statistically significant differences in drug release. The swelling and wettability of the tablets were also investigated, since these two factors influence release. Turbidity and viscosity studies revealed the formation of a complex between PAA and HPMC. The greater the turbidity due to the formation of the complex, the lower the degree of swelling. The release obtained for Carbopol 934 is greater compared with Carbopol 941 and 940, possibly due to the lower viscosity of the Carbopol. Nevertheless, the behaviour in solution is more influenced by the hydrophilic nature of the HPMC than by the formation of the complex.
|Number of pages||6|
|Journal||STP Pharma Sciences|
|Publication status||Published - 1992|