In vitro-Ex vivo Characterization of Agarose – Carbopol 934® Based Buccal Mucoadhesive Tablets Containing Benzocaine and Tibezonium Iodide as Model Drugs

The release of locally acting drugs can be targeted using mucoadhesive platform. Natural biodegradable polymers are considered as suitable contenders as mucoadhesive polymers. The aim of current research was to evaluate mucoadhesive role of agarose (AG) by preparing directly compressible tablets. AG was aided by carbopol® (CP) for simultaneous release of benzocaine (BZN) and tibezonium iodide (TIB) from mucoadhesive tablets. In order to prepare tablets, ingredients were mixed geometrically and compressed using a ZP35 rotary tablet machine. The prepared tablets were characterized for physical, ex vivo mucoadhesive time (ET) and mucoadhesive strength (MS), swellability, erosion and in vitro drugs release. The solid state studies revealed that no unusual peak in the physical mixture of ingredients through FTIR and DSC analysis. Values of weight variation and friability tests of the tablet formulations complied with USP specifications which showed that variation in the polymers did not affect physical parameters of the tablets. The highest ET (24.3 h) and MS (22.6 g) values were associated with formulation T9. Maximum erosion was observed in T1 formulation with lowest concentration of AG (10%) used in the study. Similarly, higher SI was observed with T2 (74.02%) at 6 h. The optimized tablet formulation T2 showed complete drug release after 6 h with better swelling. In addition, when polymers were used alone, AG exhibited poor MS and ET values compared to CP whereas polymers used in combination (AG-CP) exhibited much better properties. Therefore, it was concluded that AG when combined with a mucoadhesive agent like CP have much improved potential to effectively deliver drugs.