THIOLATION OF FENUGREEK SEED POLYSACCHARIDE; UTILIZATION AS A NOVEL BIOMUCOADHESIVE AGENT IN DRUG DELIVERY

Abstract

Objective: The objectives of the present work were to carry out thiol-modification (i.e., thiolation) of fenugreek polysaccharide (FP) and to assess the synthesized thiolated product (TFP) as a mucoadhesive excipient in the designing of mucoadhesive formulations (metronidazole gels and metronidazole buccal discs). Methods: Extracted CG was thiol-modified via an esterification reaction by utilizing thioglycolic acid with an acidic milieu (using hydrochloric acid). Metronidazole mucoadhesive gels and buccal discs made of extracted FP and TFP (as mucoadhesive excipients) were prepared and evaluated to assess their biomucoadhesivity. Mucoadhesive gels containing 1%w/v metronidazole were prepared using both FP and TFP (1% w/v), separately. Mucoadhesive buccal discs containing metronidazole were prepared by the compression method, where FP and TFP (100 mg) were used as mucoadhesive excipients separately, along with 50 mg lactose and 25 mg PEG 4000. Results: The yield of TFP was 53.46% and the content of the thiol group in TFP was found to be 5.18 mmol of thiol group/g of FP. FTIR analysis results indicated the thiolation of FP in the synthesized TFP. Both types of formulations (mucoadhesive gels and buccal discs) made of TFP exhibited excellent improved ex vivo biomucoadhesion and a sustained pattern of metronidazole release over a prolonged period. Conclusion: The synthesized TFP can be used as improved mucoadhesive agent in the designing of biomucoadhesive systems for drug delivery.