Optimization and validation of a method for the determination of caffeine,8-chlorotheophylline and diphenhydramine by isocratic high-performance liquid chromatography - Stress test for stability evaluation
C. Barbas et al., Optimization and validation of a method for the determination of caffeine,8-chlorotheophylline and diphenhydramine by isocratic high-performance liquid chromatography - Stress test for stability evaluation, J CHROMAT A, 870(1-2), 2000, pp. 97-103
The optimization of a HPLC method for caffeine, 8-chlorotheophylline and di
phenhydramine separation with UV detection at 229 nm is described. The cond
itions studied included: stationary phase, compositions of mobile phases wi
th pH modulators. Optimal conditions were: SymmetryShield RP8 column and ac
etonitrile-(0.01 M H3PO4-triethylamine, pH 2.8) (22:78, v/v). Validation wa
s performed using standards and a pharmaceutical preparation containing the
compounds described above. Results from both standards and samples show su
itable validation parameters. The pharmaceutical grade substances were test
ed by factors that could influence the chemical stability. These reaction m
ixtures were analyzed to evaluate the capability of the method to separate
degradation products. Degradation products did not interfere with the deter
mination of the substances tested by the assay. (C) 2000 Elsevier Science B
.V. All rights reserved.