title: Anodic polarographic determination of josamycin in formulations and spiked human urine.
abstract: The anodic polarographic behaviour of josamycin (a macrolide antibiotic) has been studied using direct current (DC(t)) polarography and differential pulse polarography (DPP). In Britton-Robinson buffers (BRb) josamycin exhibited well-defined anodic polarographic waves in the pH range 2-8. In BRb of pH 6, the diffusion-current constant was 1.62 microA mmol(-1) (n = 6). The current-concentration plots are rectilinear over the range 10-50 and 5-40 microg/ml using the DC(t) and DPP modes, respectively, with a detection limit of 4.83 x 10(-6) M adopting the DPP mode. The method was applied to commercial tablets adopting both DC(t) and DPP modes, the recoveries % were 99.13 +/- 2.22 (n = 10) and 99.82 +/- 1.82 (n = 7), respectively. The method was further extended to the in vitro determination of josamycin in human urine, the recovery % (n = 6) was 100.06 +/- 2.84. The number of electrons involved in the electrode process could be accomplished and a proposal of electrode reaction was presented.
authors.affiliation: Department of Pharmaceutical Chemistry, King Saud University, College of Pharmacy, P.O. Box 2457, Riyadh 11451, Saudi Arabia. ffbelal@yahoo.com
authors.forename: Fathalla
authors.initials: F
authors.lastname: Belal
authors.forename: Abdel-Rahman A
authors.initials: AR
authors.lastname: Al-Majed
authors.forename: Kamal E E
authors.initials: KE
authors.lastname: Ibrahim
authors.forename: Nasr Y
authors.initials: NY
authors.lastname: Khalil
mesh_terms: D000447:Aldehydes / Q000737:chemistry; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000652:urine*; D002626:Chemistry, Pharmaceutical; D004566:Electrodes; D006801:Humans; D006863:Hydrogen-Ion Concentration; D015570:Josamycin / Q000737:chemistry / Q000652:urine*; D010084:Oxidation-Reduction; D011048:Polarography / Q000379:methods*; D013607:Tablets
chemical_list: D000447:Aldehydes; D000900:Anti-Bacterial Agents; D013607:Tablets; D015570:Josamycin