Spectroscopic Investigations of a Controlled Release Mucoadhesive Suspension

Abstract

Norfloxacin, an antibacterial agent, is having low solubility in aqueous solution. Moreover, the drug possesses short half-life, so frequent dosing is required. To overcome these problems, many investigators have prepared different formulations of Norfloxacin. But till now very few formulations are available from which the drug is absorbed uniformly, so that safe and effective blood level of Norfloxacin could be maintained for a prolonged period. To fulfill this requirement, in the present study, a controlled release drug delivery system was designed and chemical interaction between Norfloxacin and a polymer (HPMC), used in the formulation, was studied by FTIR and Raman Spectroscopy. Ultrasonication method was used for preparation of mucoadhesive Norfloxacin formulation in which drug to polymer weight ratio being 1:5. FTIR (400 cm-1 to 4000 cm-1 region) and Raman (140 to 2400 cm-1 Keywords: Norfloxacin, HPMC, Mucoadhesive suspension, FTIR, Raman Spectroscopy. region) Spectroscopic studies were carried out and spectra were used for interpretation. From the spectral interpretation, it has been found that in formulation, the carboxylic groups of Norfloxacin and hydroxyl groups of HPMC undergo chemical interaction leading to esterification and hydrogen bonding (both intermolecular and polymeric). Formation of micellies due to esterification and hydrogen bonding causes more drug entrapment and formation of a stable formulation. As a result, the mucoadhesive formulation of Norfloxacin may give better controlled release and mucoadhesive action in the gastrointestinal tract. Hence, HPMC could be considered as an effective carrier of Norfloxacin.