title: Circular dichroism spectroscopy: An efficient approach for the quantitation of ampicillin in presence of cloxacillin.
abstract: Ampicillin exhibited a negative and a positive cotton effects on the circular dichroism (CD) spectra in the wavelength range of 200-280nm. Cloxacillin showed a positive cotton band peaking at 228nm. Three sensitive, precise and accurate CD spectroscopic methods have been developed for the determination of ampicillin and cloxacillin. Method A was used for the determination of ampicillin in presence of cloxacillin by measuring ellipticity at 206nm. Method B and C were employed to determine ampicillin and cloxacillin based on evaluation of ellipticity at 233nm and 228nm, respectively. Methods A, B and C showed linearity in the concentration range of 10-40μgmL(-1), 5-40μgmL(-1) ampicillin and 10-80μgmL(-1) cloxacillin, respectively. The method A was successfully applied to the determination of ampicillin in commercial dosage forms containing equivalent amount of cloxacillin.
authors.affiliation: Department of Chemistry, Aligarh Muslim University, Aligarh-202002 (UP), India. Electronic address: nafisurrahman05@gmail.com.
authors.forename: Nafisur
authors.initials: N
authors.lastname: Rahman
authors.affiliation: Department of Chemistry, Aligarh Muslim University, Aligarh-202002 (UP), India.
authors.forename: Sumaiya
authors.initials: S
authors.lastname: Khan
mesh_terms: D000667:Ampicillin / Q000032:analysis* / Q000737:chemistry; D002138:Calibration; D002942:Circular Dichroism / Q000379:methods*; D003023:Cloxacillin / Q000032:analysis* / Q000737:chemistry; D012044:Regression Analysis
chemical_list: D000667:Ampicillin; D003023:Cloxacillin
keywords: Ampicillin; Circular dichroism spectra; Cloxacillin; Pharmaceutical formulation; Validation