Gas chromatographic determination of diisopyramide in the presence of some butyrophenones in human plasma.

A gas chromatographic procedure with flame ionization detection for the simultaneous determination of diisopyramide and butyrophenones in plasma was developed and evaluated. The quantitative analysis of diisopyramide and butyrophenones (BTPs) was performed in gas chromatograph equipped with packed column (glass column packed with 3% of phenylmethyl silicone-20% ph.), with previous Solid Phase Extraction (SPE) of drugs in C18 minicolumns. For all the drugs considered the accuracy of the proposed method has been evaluated through the recovery test which fell in the range 93-99%, once the absence of matrix interferences has been verified. The precision, expressed as coefficient of variation (CV%), has been of the order of 4%. A 15 m x 0.32 mm i.d. crosslinked, 5% phenylmethyl silicone-coated fused-silica column was also quantitatively utilized and samples were injected using the on-column mode.

Simultaneous determination of propranolol or metoprolol in the presence of butyrophenones in human plasma by gas chromatography with mass spectrometry.

A method has been developed for the simultaneous gas chromatographic determination of propranolol or metoprolol and butyrophenones butyrophenones in human plasma in vitro. The drugs were extracted from plasma by solid-phase extraction. Calibration graphs were linear in the 50-300-ng/mL range. The recovery of the compounds was 80-90%. The sensitivity of the method was adequate for the determination of the drugs at toxic concentrations and at therapeutic levels. It is a simple, rapid, and reproducible method for the simultaneous determination of propranolol or metoprolol and some butyrophenones. The minimum detectable concentration was 50 ng/mL with a flame ionization detector and 10 ng/mL with a mass spectrometer detector.

Simultaneous determination of propranolol or metoprolol in the presence of benzodiazepines in the plasma by gas chromatography.

A method for the simultaneous gas chromatographic determination of propranolol and metoprolol and some benzodiazepines in human plasma is described. After the addition of an internal standard, plasma samples were adjusted to pH 8.5 and extracted by SPE chromatography. The analysis was performed by GC with packed and capillary columns, using a FID detector. The quantitative recovery was reported. The assay response was linear in concentration range 50-300 ng/mL for propranolol-benzodiazepine and 100-350 ng/mL for metoprolol-benzodiazepine mixtures.

Simultaneous determination of quinidine and butyrophenones in human plasma by GC-MS.

This report describes a sensitive GC and HRGC-MS procedure for the simultaneous determination of Quinidine and some bytyrophenone drugs in human plasma. The quantitative response is linear from 50-250 ng/ml using Pipamperone as international standard. It is suitable for clinical analysis at therapeutic levels.

Opioid peptides. Structure-activity relationships in [OGly4] dermorphin tetrapeptides. X.

We describe the synthesis and preliminary in vitro and in vivo pharmacological tests of four [OGly4] tetrapeptide analogues of the opioid heptapeptide dermorphin H-Tyr-D-Ala-Phe-Gly-Tyr-Pro-Ser-NH2. The modification obtained by substituting aminoxy-acetic acid (OGly) for Gly4 provided analogues with substantial reduction of activity.