Ionotropically-gelled mucoadhesive beads for oral metformin HCl delivery: Formulation, optimization and antidiabetic evaluation

The work investigates the development and optimization of ionotropically-gelled mucoadhesive beads composed of tamarind seed polysaccharide (TSP)-alginate polymer-blend for oral delivery of metformin HCl using 32 factorial design. The optimized mucoadhesive beads exhibited 94.86 ± 3.92 % drug encapsulation efficiency and good mucoadhesivity with the biological membrane in wash-off test, and sustained drug release profile over 10 h. The in vitro drug release from these beads was followed controlled-release (zero-order) pattern (R2 = 0.9873 to 0.9980) with super case-II transport mechanism. The optimized TSPalginate mucoadhesive beads containing metformin HCl showed significant antidiabetic effect in alloxan-induced diabetic rats over prolonged period after oral administration. These results clearly demonstrated that the developed mucoadhesive beads was found suitable for prolonged systemic absorption of metformin HCl through sustained drug release and mucoadhesive properties after oral administration in the management of non-insulin dependent diabetes mellitus with maintenance of blood glucose level.