0 A rapid, sensitive, and specific fluorometric TLC procedure for the estimation of hydroflumethiazide in human biological fluids is described. The drug was removed from plasma in a single extraction step and applied to a TLC plate of silica gel. After development, the plate was scanned in a spectrodensitometer equipped to measure fluorescence below 400 nm. Quantitation was achieved by comparing the areas under the peaks obtained from the unknowns t o those obtained from standards applied to the same plate. The limit of detection was 10 ng of drug/ml of plasma. A mean recovery value of 99.7% was obtained when the drug was extracted from spiked human plasma samples, while 97.5% of drug was recovered from spiked human urine samples. T o test the validity of the method, a beagle dog was given an intravenous dose of hydroflumethiazide, and postadministration blood and urine samples were collected and analyzed.
Keyphrases 0 Hydroflumethiazide-fluorometric TLC analysis in plasma and urine 0 TLC, spectrofluorodensitometry-analysis, hydroflumethiazide in plasma and urine Spectrofluorodensitometry-analysis, hydroflumethiazide Eberbach, Ann Arbor, Mich. N-Evap, Organomation Assoc.