Assessing the bioadhesivity of Acconon MC 8-2 EP/NF for gastroretention of floating microsponges of loratadine and achieving controlled drug delivery

The aim of the present work was to assess the feasibility of Acconon MC8-2 EP/NF as a bioadhesive material for developing controlled release gastroretentive microsponges of loratadine. Modified emulsion-solvent diffusion method was employed for the preparation of microsponges (F1-F9) based on  32 factorial design. The amount of ethyl cellulose (EC) and polyvinyl alcohol (PVA) were selected as independent variables while particle size, entrapment efficiency and %CDR were designated as dependent variables. The formulation (F1) with least particle size of 54 ± 2.37µm, entrapment efficiency of 65.98 ± 2.21 % and CDR of 88.15 ± 1.59% at 8 h that followed zero order release kinetics was selected as optimized formulation. F1 was re-fabricated as bioadhesive microsponges (BF1) using Acconon MC 8-2 and assessed.  The particle size of BF1increased to 84 ± 2.29 µm whereas the entrapment efficiency lowered to 55.19 ± 1.36% in comparison to F1. However, the CDR8h from BF1 (81.65 ± 3.37%) was comparable to F1. Dynamic in vitro bioadhesion test confirmed the bioadhesive property of BF1. Ex vivo permeation across gastric mucin depicted 52.87% CDP8h that followed zero order kinetics (r2 = 0.9885). Scanning electron microscopy revealed spherical and highly porous surface. The FTIR studies revealed no chemical interaction between drug and excipients. Hence, the study affirmed the bioadhesive characteristics of Acconon MC 8-2 EP/NF for development of controlled release biaodhesive floating microsponges of loratadine.