Mucoadhesive properties of cross-linked high amylose starch derivatives.
Acetate (Ac-), aminoethyl (AE-) and carboxymethyl (CM-)derivatives of cross-linked high amylose starch (HASCL-6) were previously shown to control, over more than 20h, the release of drugs from highly loaded (up to 60% drug) monolithic tablets. It was now of interest to evaluate their mucoadhesive characteristics in view of further utilization in buccal or vaginal transmucosal delivery. The present study shows that ionic AE-HASCL-6 and CM-HASCL-6 derivatives exhibit higher mucoadhesive properties than neutral HASCL-6 and Ac-HASCL-6, suggesting that the ionic groups introduced on cross-linked starch chains play a role in the bioadhesion process. The adhesiveness seemed related to capillary attraction forces. Surface adhesion parameters were calculated for slabs based on the mentioned polymers and corroborated with their swelling behavior at various pH changes. The positively charged AE-derivatives presented a higher adhesion at acidic pH, being thus recommended for vaginal delivery, whereas the negatively charged derivatives (CM-HASCL-6) exhibited a better adhesion at neutral pH, being thus more appropriate for buccal delivery.
Mulhbacher
Jérôme
J
Department of Chemistry and Biochemistry, Centre BioMed, Université du Québec à Montréal, CP 8888, Succ. Centre-Ville, Montréal, Québec H3C 3P8, Canada.
Ispas-Szabo
Pompilia
P
Ouellet
Mathieu
M
Alex
Serge
S
Mateescu
Mircea Alexandru
MA
D000268:Adhesiveness; D000688:Amylose / Q000737:chemistry*; D003432:Cross-Linking Reagents; D003692:Delayed-Action Preparations; D016503:Drug Delivery Systems; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D009077:Mucins; D009092:Mucous Membrane; D013213:Starch / Q000737:chemistry*; D013607:Tablets
D003432:Cross-Linking Reagents; D003692:Delayed-Action Preparations; D009077:Mucins; D013607:Tablets; D013213:Starch; D000688:Amylose