Protein binding studies of furosemide and penbutolol.

Serum protein binding of furosemide and penbutolol, the active principles of Betasemid (Hoe 9358), was studied by equilibrium dialysis. Membranes from commercial dialysis tubes were used within commercially available cells. Serum drug and portion unbound in buffer were determined by quantitative thin-layer chromatography.

Thin-layer chromatographic determination of imipramine and desipramine in human plasma and urine at single-dose levels.

Thin-layer chromatographic methods were up-dated for pharmacokinetic studies of imipramine in plasma and urine. The free parent compound and its free desmethyl metabolite desipramine are determined in plasma. Conjugates of both compounds in urine are cleaved on treatment with glucuronidase/arylsulfatase.

Thin-layer chromatographic determination of procainamide and N-acetylprocainamide in human serum and urine at single-dose levels.

Thin-layer chromatographic methods were applied for bioavailability studies of procainamide in serum and urine. Detection of the parent compound and the major metabolite was performed in the ultraviolet range at 275 nm. Using 100-microliter samples, detection limits were 60 ng of procainamide-HCl per ml serum and 7 micrograms/ml urine, and 60 ng of N-acetylprocainamide-HCl per ml serum and 5 micrograms/ml urine.

Quantitative thin-layer chromatography for routine determination of nomifensine and its metabolites in human urine.

For pharmacokinetic studies with nomifensine, a thin-layer chromatographic (TLC) assay for human urine was introduced. Following acid cleavage of the N-glucuronides, nomifensine and its three main metabolites (M1, M2 and M3) were extracted at pH 10. An aliquot was transferred on to a silica gel plate.

Thin-layer chromatographic determination of major metamizole metabolites in serum and urine.

Thin-layer chromatographic (TLC) methods were developed for pharmacokinetic studies of major metamizole metabolites in serum and urine. These methods proved practicable, selective, accurate and sensitive with detection limits as follows: 4-methylaminoantipyrine 0.6 micrograms/ml serum and 2.

High-performance liquid column and thin-layer chromatographic determination of human serum glibenclamide at therapeutic levels.

For glibenclamide bioavailability studies in serum, high-performance liquid column and thin-layer chromatographic methods were introduced. Both methods are specific, accurate and sensitive with detection limits of at least 5 ng of glibenclamide per ml of serum. Detection is performed in the ultraviolet at wavelengths of 200 nm for liquid chromatography or 300 nm for thin-layer chromatography.

Quantitative thin-layer and high-performance liquid chromatographic determination of the diuretic agent 2-chloro-5-[44-hydroxy-3-methyl-2-(methylimino)-4-thiazolidinyl]benzenesulphonamide hydrochloride in serum and urine.

Sensitive and specific thin-layer (TLC) and high-performance liquid chromatographic (HPLC) methods were developed for the determination of the diuretic agent 2-chloro-5-[4-hydroxy-3-methyl-2-(methylimino)-4-thiazolidinyl]benzenesulphonamide hydrochloride (HOE 740). HOE 740 can be determined in serum by HPLC. The detection is performed at a very short wavelength (202 nm), resulting in a detection limit of 10 ng/ml.