Novel thiolated Ceasalpinia Pulcherrima: synthesis, characterization and evaluation as mucoadhesive in situ gelling agent

Purpose: The objective of present study was to enhance bioadhesive potential of Ceasalpinia pulcherrima (CP) by thiolation.

 

Method: Thiolation of CP was achieved with esterification with thioglycolic acid.

 

Result: Thiolated Ceasalpinia pulcherrima (TCP) was characterized by nuclear magnetic radiation, differential scanning calorimetry, and X-ray crystallography analysis. TCP was determined to possess 4.803mmol of thiol groups/g of polymer by Ellman’s method. Comparative evaluation of mucoadhesive property of metoclopramide hydrochloride containing in situ gel system of CP and TCP using sheep nasal mucosa revealed higher ex vivo bioadhesion time of TCP as compared to CP. Improved mucoadhesive property of TCP over the CP can be attributed to the formation of disulfide bond between mucus and TCP. Ex vivo permeation study conducted using sheep nasal showed improved drug permeation in formulation based on TCP.

 

Conclusion: Thiolation of CP improves its bioadhesion and drug permeation without affecting the resultant gel property.