Ultraviolet determination of chlordimeform in cattle dipping baths and sprays
Machin, M.V.; Dingle, J.H.
Journal - Association of Official Analytical Chemists 60(3): 696-698
1977
ISSN/ISBN: 0004-5756 PMID: 858706 Document Number: 113366
A simple and reliable method has been developed for determining chlordimeform, which is used to control Boophilus microplus (Can.) in New South Wales. A preliminary clean-up converts chlordimeform to its hydrochloride and removes ultraviolet-absorbing impurities. The aqueous acid phase containing chlordimeform hydrochloride is diluted and passed through a silica gel column. The column effluent is used as the reference solution and a portion not eluted through silica gel is used as the sample solution in the spectrophotometer. The absorbance at 240 mm is measured, and the chlordimeform concentration is determined from the calibration graph. The method applied to solutions of acaricides gives good results in the range of 0.02-0.06% w/v chlordimeform; higher concentrations may be determined by appropriate dilutions.