Fabrication and in vitro evaluation of mucoadhesive ondansetron hydrochloride beads for the management of emesis in chemotherapy

Development of nitazoxanide-loaded colon-targeted formulation for intestinal parasitic infections: centre composite design-based optimization and characterization

Background

The current investigation is focused on the development and characterization of Eudragit S100 coated nitazoxanide-loaded microbeads as colon-targeted system utilizing central composite design (CCD) and desirability function. The study initiated with the selection of a BCS class II drug nitazoxanide and its preformulation screening with excipients, selection of polymer and identification of concentration for CCD, selection of optimized formulation based on desirability function, and in vitro release studies in simulated gastric and colonic media and stability studies. A two-factor, three-level CCD was employed with two independent variables, i.e. X1 (chitosan % w/v) and X2 (sodium tripolyphosphate % w/v), and three dependent variables, i.e. Y1 (particle size in micrometres), Y2 (percentage yield) and Y3 (percent entrapment efficiency), were chosen. Additionally, surface morphology, mucoadhesion and in vitro drug release studies were also conducted.

Result

Chitosan concentration showing maximum entrapment and optimum particle size was selected to formulate chitosan beads. The polynomial equation and model graphs obtained from the Design-Expert were utilized to examine the effect of independent variables on responses. The effect of formulation composition was found to be significant (p ˂ 0.05). Based on the desirability function, the optimized formulation was found to have 910.14 μm ± 1.03 particle size, 91.84% ± 0.64 percentage yield and 84.75% ± 0.38 entrapment efficiency with a desirability of 0.961. Furthermore, the formulations were characterized for in vitro drug release in simulated colonic media (2% rat caecal content) and have shown a sustained release of ∼ 92% up to 24 h as compared to in vitro release in simulated gastric fluid.

Conclusion

The possibility of formulation in enhancing percentage yield and entrapment efficiency of nitazoxanide and the utilization of CCD helps to effectively integrate nitazoxanide microbeads into a potential pharmaceutical dosage form for sustained release.

Formulation and Optimization of Oral Mucoadhesive Patches of Myrtus Communis by Box Behnken Design

Purpose: Recurrent aphthous stomatitis (RAS) is the most common painful ulcerative disease of oral mucosa happening in ~20% of people. Aimed to develop Myrtus communis L. (Myrtle) containing oral patches, we applied box-behnken design to evaluate the effect of polymers such as Polyvinyl pyrrolidone (PVP), Gelatin, Methylcellulose (MC) and Pectin. Methods: The patches properties such as tensile strength, folding endurance, swelling index, thickness, mucoadhesive strength and the pattern of myrtle release were evaluated as dependent variables. Then, the model was adjusted according to the best fitted equation with box behnken design. Results: The results indicated that preparation of myrtle patch with hydrophilic polymers showed the disintegration time up to 24h and more. Using of polyvinyl pyrrolidone as a water soluble polymer and a pore-former polymer led to faster release of soluble materials from the patch to 29 (min-1). Also it decreases swelling index by increasing the patch disintegration. Gelatin and Pectin, with rigid matrix and water interaction properties, decreased the swelling ratio. Pectin increased the tensile strength, but gelatin produced an opposite effect. Thinner Myrtle patch (about 28µm) was obtained by formulation of methyl cellulose with equal ratio with polyvinyl pyrrolidone or gelatin. Conclusion: Altogether, the analysis showed that the optimal formulation was achieved with of 35.04 mg of Gelatin, 7.22 mg of Pectin, 7.20 mg of polyvinyl pyrrolidone, 50.52 mg of methyl cellulose and 20 mg of Myrtle extract.

Chitosan lactate wafer as a platform for the buccal delivery of tizanidine HCl: in vitro and in vivo performance

Tizanidine HCl is a skeletal muscle relaxant that suffers from extensive hepatic metabolism resulting in 34-40% oral bioavailability. It also suffers from short half-life (2.1-4.2h) that necessitates frequent administration thus reducing patient compliance. In addition, tizanidine HCl is water soluble, so it is a challenging candidate for controlled drug delivery. In our study, tizanidine was encapsulated in chitosan lactate beads cross-linked with sodium tripolyphosphate. The beads were further incorporated into chitosan lactate wafer to be easily applied to buccal mucosa, aiming to bypass the hepatic metabolism. A central composite face-centered design was applied to statistically optimize the formulation variables; tripolyphosphate concentration, chitosan lactate concentration and polymer/drug ratio. The optimized formula suggested by the software composed of; 3.03% tripolyphosphate, 4.92% chitosan lactate and 2.13 polymer/drug ratio. It provided encapsulation efficiency of 56.5% and controlled tizanidine release over 8h. It is also characterized by being mucoadhesive and nonirritant. Pharmacokinetic parameters of tizanidine from the optimized formula were compared to those of the immediate release tablet, Sirdalud(®), as reference in human volunteers using a randomized crossover design. Significant increase was observed for Tmax and AUC(0-∞). The increase in relative bioavailability of TIZ from the optimized formula was 2.27 fold.