Construction and in vitro characterization of an optimized porosity-enabled amalgamated matrix for sustained transbuccal drug delivery

This research focused on constructing and characterizing an optimized porosity-enabled amalgamated matrix (P-EAM) for sustained transbuccal drug delivery. An interphase, co-particulate, co-solvent, homogenization technique and lyophilization guided through a Box–Behnken experimental design was employed in the fabrication, characterization and optimization of 15 P-EAMs. The effects of varying factor levels on the characteristic in vitro physicochemical performances of the P-EAMs were explored. Formulations had an average weight of 128.44 ± 3.48 mg with a dimensional size of 8 mm by 5 mm. Surface morphology showed varieties of pore structures, widespread distributions and uneven interconnectors. Satisfactory drug-loading was achieved (53.14 ± 2.19–99.02 ± 0.74%). Overall amount of drug released in 8 h was measured by the MDT50% value which ranged between 22.50 and 225.00 min. Formulation demonstrated significant levels of ex vivo bioadhesive strength measured as detachment force (Fdet = 0.964 ± 0.015 to 1.042 ± 0.025 N) and work of adhesion (ωadh = 0.0014 ± 0.00005 to 0.0028 ± 0.00008 J). The potential of the P-EAMs to initiate and sustain ex vivo transbuccal permeation of drug was shown and measured as a cumulative value of between 25.02 ± 0.85 and 82.21 ± 0.57% in 8 h. Formulations were mesoporous in nature with pore sizes ranging from 40 to 100 Å characterized by the presence of interconnectors. Statistical constraints were simultaneously set to obtain levels of independent variables that optimized the P-EAM formulation.