Stability-indicating method for the determination of clorazepate dipotassium-I. Via its final degradation products.
A sensitive spectrophotometric procedure is described for the determination of 1,4-benzodiazepine (clorazepate dipotassium) in the presence of its degradation products. The procedure is based on acid hydrolysis of clorazepate dipotassium to yield its final degradation products viz., 2-amino-5-chlorobenzophenone and glycine. The amino-chlorobenzophrenone is extracted from the neutralized hydrolysate with diethyl ether, the extract is evaporated, the residue is dissolved in methanol and its absorbance measured at about 240 nm or 380 nm. Glycine, left in the aqueous layer after etherial extraction of aminochlorobenzophenone, is treated with ninhydrin reagent in the presence of pyridine and the bluish violet colour formed is measured at about 560 nm. The suggested procedures determine 20-100 mg of clorazepate dipotassium via its degradation products aminochlorobenzophenone and glycine with mean accuracies of 100.0 +/- 0.5% at 560 nm, 100.2 +/- 0.6% at 380 nm and 99.8 +/- 0.5%. The suggested procedures are suitable for stability-testing of clorazepate dipotassium in bulk powder and in pharmaceutical preparations.
El-Bardicy
M G
MG
Analytical Chemistry Department, Faculty of Pharmacy, Cairo University, Cairo, Egypt.
Bebawy
L I
LI
Amer
M M
MM