Development, characterization and optimization of polymeric mucoadhesive microcapsules containing anticancer agent using response surface method: in vitro and in vivo study

The present research work covenants the preparation, characterisation and optimisation of mucoadhesive microcapsules containing paclitaxel through ionic gelation method using 32 statistical factorial designs. The effect of mixing proportion of primary polymer sodium alginate to copolymer (X1) and speed of magnetic stirrer (X2) on the microcapsules size (Y1), efficiency of paclitaxel encapsulation (Y2), and percentage yield (Y3) was optimised. The morphology of microcapsules was characterised and evaluated by in vitro and in vivo tests to study the swelling characteristics, mucoadhesion and drug release characteristics, followed by MTT assay on human HT-29 colon cancer cell lines. The size of prepared microcapsules was within the range of 361 ± 4.50 to 931 ± 22.41; encapsulation efficiency (%) was within the range of 42.72 ± 0.43 to 98.12 ± 0.43 %. The in vitro paclitaxel released over 24 hours were in a range of 82.15 ± 3.43 % to 96.75 ± 2.41 %. The controlled release pattern of paclitaxel was observed from the in vitro drug release study of microcapsules. The prepared microcapsules that showed better mucoadhesion were in the range of 73.66 ± 1.42 to 97.85 ± 1.08 % for a period of 6 h. The in vivo pharmacokinetic study conducted in rats resulted in high Tmax, the area under the curve and mean residence time for microcapsules as compared to that of the marketed formulation. It could be concluded that the microcapsules containing povidone polymer showed superior results.