Collaborative study of a semiautomated method for the analysis of acenocoumarol, phenprocoumon, and potassium warfarin tablets.

This collaborative study was undertaken to determine if the anticoagulants acenocoumarol, phenprocoumon, and potassium warfarin could be analyzed by the automated analysis system described in the collaborative study for the analysis of sodium warfarin and dicumarol. Collaborators were supplied with a composited tablet sample of each anticoagulant. Results agreed well with the National Formulary methods for phenprocoumon and potassium warfarin, and an unpublished method for acenocoumarol. For acenocoumarol, coefficients of variation on individual sets of data ranged from 0.30 to 1.94% For phenprocoumon, coefficients of variation ranged from 0.52 to 1.20%. For potassium warfarin, coefficients of variation ranged from 0.54 to 1.79%. The results of this study show that acenocoumarol, phenprocoumon, and potassium warfarin can be analyzed by the official AOAC method for the analysis of sodium warfarin and dicumarol tablets.