Mucoadhesion and cytotoxicity of powders for nasal drug delivery
Alison B Lansley, Xiaoqian Ding, Oluwatosin S Adelowo & Matthew Ingram
Biomaterials and Drug Delivery Research and Enterprise Group, University of Brighton, Lewes Road, Brighton, BN2 4GJ, UK
Summary
The mucoadhesiveness and cytotoxicity of a range of powders was studied to test the hypothesis that mucoadhesive powders can be used safely in the nasal cavity to aid in the retention of the nasal formulations and improve the effectiveness of nasal products.
The mucoadhesiveness of a range of powders (hydroxypropyl methyl cellulose (HPMC 400 and 4000), pectin, carboxymethylcellulose, sodium salt (CMC) and colloidal microcrystalline cellulose (cMCC)) was measured using a Texture Analyser and their toxicity to a human bronchial epithelial cell line (16HBE14o-) was measured using an MTT assay.
The mucoadhesiveness of the powders studied tended to decrease in the following order with HPMC 400 > HPMC 4000 > CMC > Pectin > cMCC > no sample. Generally, HPMC 400, HPMC 4000 and CMC were more mucoadhesive than cMCC (P<0.05). The cytotoxicity of the powders appeared to depend on the volume of cell culture medium available to hydrate the powder. Apart from cMCC, which was not cytotoxic in the presence of 0, 50 and 100 mL medium, all powders were toxic in the absence of medium (p<0.05). All powders, apart from pectin, were non-toxic in the presence of 50 and 100 mL medium.
The mucoadhesiveness and cytotoxicity of different polymers, when applied in powdered form, is variable. Therefore, the choice of powdered polymer is important in optimising the retention of powdered nasal formulations while avoiding toxicity to the nasal epithelium.