FTIR and Raman Spectroscopy as a Tool for Analyzing Sustained Release Hydrogel of Ciprofloxacin/Carbopol Polymer

Abstract

Ciprofloxacin, an antibacterial agent, is having low solubility in aqueous solution and high rate of absorption from the stomach. It is precipitated at alkaline pH which leads to erratic absorption of the drug from small intestine. To overcome these difficulties, many researchers have prepared different formulations of Ciprofloxacin. But till now very few formulations are available from which the drug is absorbed uniformly, so that safe and effective blood level of Ciprofloxacin can be maintained for a prolonged period. To fulfill this requirement, in the present study, a sustained release drug delivery system (hydrogel) has been designed and chemical interaction between Ciprofloxacin and polymer in hydrogel has been studied by FTIR and Raman Spectroscopy. Methods: Ultrasonication method was used for preparation of hydrogel of the Ciprofloxacin, taking Carbopol 934 polymer with drug to polymer weight ratio 1:5. FTIR (400 cm-1 to 4000 cm-1 region) and Raman (140 to 2400 cm-1 region) Spectroscopic studies were carried out and spectra were used for interpretation. Results: From the spectral interpretation, it has been found that in hydrogel, the carboxylic groups of Ciprofloxacin and hydroxyl groups of Carbopol934 undergo chemical interaction leading to esterification and hydrogen bonding (both intermolecular and polymeric). Conclusions: The formation of micelles due to esterification and hydrogen bonding causes more drug entrapment and formation of a stable hydrogel, as a result of which, the hydrogel of Ciprofloxacin gives better controlled release and mucoadhesive action in the gastrointestinal tract and hence Carbopol934 can be considered as an effective carrier of Ciprofloxacin.