title: Degradation kinetics of 4-dedimethylamino sancycline, a new anti-tumor agent, in aqueous solutions.
abstract: The kinetics of degradation of the new anti-tumor drug, 4-dedimethylamino sancycline (col-3) in aqueous solution at 25oC were investigated by high-pressure liquid chromatography (HPLC) over the pH-range of 2-10. The influences of pH, buffer concentration, light, temperature, and some additives on the degradation rate were studied. The degradation of col-3 was found to follow first order kinetics. A rate expression covering the degradation of the various ionic forms of the drug was derived and shown to account for the shape of the experimental pH-rate profile. Under basic conditions, the degradation of col-3 involves oxidation, which is catalyzed by metal ions and inhibited by EDTA and Sodium bisulfite.
authors.affiliation: Department of Pharmacy Practice and Science, College of Pharmacy, The University of Arizona, 1703 E. Mabel St., P.O. Box 210207, Tucson, AZ 85721-0207, USA.
authors.forename: S
authors.initials: S
authors.lastname: Pinsuwan
authors.forename: F A
authors.initials: FA
authors.lastname: Alvarez-Núñez
authors.forename: E S
authors.initials: ES
authors.lastname: Tabibi
authors.forename: S H
authors.initials: SH
authors.lastname: Yalkowsky
mesh_terms: D000903:Antibiotics, Antineoplastic / Q000737:chemistry*; D002021:Buffers; D002384:Catalysis; D004355:Drug Stability; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008027:Light; D010777:Photochemistry; D012996:Solutions; D013696:Temperature; D013752:Tetracycline / Q000737:chemistry*; D013754:Tetracyclines; D014867:Water / Q000737:chemistry
chemical_list: D000903:Antibiotics, Antineoplastic; D002021:Buffers; D012996:Solutions; D013754:Tetracyclines; C117155:tetracycline CMT-3; D014867:Water; D013752:Tetracycline