title: Investigation of enhancement of solubility of norfloxacin beta-cyclodextrin in presence of acidic solubilizing additives.
abstract: The present study is aimed at improving the solubility of a poorly water-soluble drug, norfloxacin by incorporating solubilizing additives such as ascorbic acid and citric acid into the beta-cyclodextrin complexes. Norfloxacin, being amphoteric in nature, exhibits a higher solubility at pH below 4 and above 8. Addition of substances like ascorbic acid and citric acid in beta-cyclodextrin complexes reduces the pH of the immediate microenvironment of the drug below pH 4. In the present work, beta-cyclodextrin complexes of norfloxacin were prepared along with solubilizing additives such as citric acid and ascorbic acid in various proportion and the dissolution profile was performed in both HCl buffer, pH 1.2 and phosphate buffer, pH 7.4. The results have shown an enhanced dissolution rate in both media. DSC and IR spectral studies performed on the solid complexes have shown that there is no interaction of the drug with the additives and beta-cyclodextrin. Disc diffusion studies have shown larger diameters of zone of inhibition indicating a greater diffusivity of the drug into the agar medium.
authors.affiliation: D.J. College of Pharmacy, Niwari Road, Modinagar-201204, Uttar Pradesh, India. kamalpharmacist@rediffmail.com
authors.forename: Kamal
authors.initials: K
authors.lastname: Dua
authors.forename: M V
authors.initials: MV
authors.lastname: Ramana
authors.forename: U V Singh
authors.initials: UV
authors.lastname: Sara
authors.forename: M
authors.initials: M
authors.lastname: Himaja
authors.forename: Abhinav
authors.initials: A
authors.lastname: Agrawal
authors.forename: Vaibhav
authors.initials: V
authors.lastname: Garg
authors.forename: Kavita
authors.initials: K
authors.lastname: Pabreja
mesh_terms: D000890:Anti-Infective Agents / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology; D001205:Ascorbic Acid / Q000737:chemistry; D001412:Bacillus subtilis / Q000187:drug effects; D019343:Citric Acid / Q000737:chemistry; D004926:Escherichia coli / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D009643:Norfloxacin / Q000737:chemistry / Q000493:pharmacokinetics* / Q000494:pharmacology; D010316:Particle Size; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D012995:Solubility; D013055:Spectrophotometry, Infrared / Q000379:methods; D013211:Staphylococcus aureus / Q000187:drug effects; D013678:Technology, Pharmaceutical / Q000379:methods*; D013696:Temperature; D017155:Wettability; D047392:beta-Cyclodextrins / Q000737:chemistry / Q000493:pharmacokinetics* / Q000494:pharmacology
chemical_list: D000890:Anti-Infective Agents; D047392:beta-Cyclodextrins; D019343:Citric Acid; C031215:betadex; D009643:Norfloxacin; D001205:Ascorbic Acid