ABSTRACT
A sensitive, specific procedure for the determination of dextromethorphan in plasma and urine in dogs is described. The use of a semi-microbore column, 2.1 mm i.d. X 25 cm resulted in a detection limit of 1 ng/mL in plasma and 25 ng/mL in urine. Plasma (3 mL) is extracted in CCl4 and the drug is back-extracted with 3% acetic acid. The chromatographic separation is carried out using a 5-micron particle size octadecyl-bonded column, and the drug is monitored by a fluorescence detector. The results after 10-mg oral administrations of dextromethorphan to dogs are provided.
Subject(s)
Body Fluids/analysis , Dextromethorphan/analysis , Levorphanol/analogs & derivatives , Chromatography, High Pressure Liquid , Humans , Spectrophotometry, UltravioletABSTRACT
The quantitative determinations of combinations of antihistamine and decongestant drugs including phenylephrine, dl-ephedrine, psi-ephedrine, phenylpropanolamine, pyrilamine, pheniramine, l-ephedrine, chlorpheniramine, brompheniramine, oxymetazoline, naphazoline, and antazoline contained in solid and liquid dosage forms are described. All active ingredients except the ephedrine optical isomers were separated from other ingredients with ion-paired high-pressure liquid chromatography. Manipulation of the mobile phase either by changing the hydroalcoholic ratio or by changing the alkyl chain length of the counterion (sulfonic acid) for achieving optimum separations is discussed. The method is simple, short, accurate, and precise.
Subject(s)
Histamine H1 Antagonists/analysis , Nasal Decongestants/analysis , Chromatography, Liquid , Delayed-Action Preparations , Methods , Sympathomimetics/analysis , Tablets/analysisABSTRACT
A fast, sensitive and specific method for the determination of chlorpheniramine in plasma is described. The drug was extracted with diethylether, back extracted in hydrochloric acid and reextracted in diethylether. The extract was evaporated to dryness and reconstituted in isopropyl alcohol. The isopropyl alcoholic solution was gas chromatographed without any derivatization and the detection was carried out using a nitrogen sensitive detector. The mean recovery of chlorpheniramine was found to be 96% and a drug level as low as 0.5 ng/ml can be accurately measured.
Subject(s)
Chlorpheniramine/blood , Animals , Chromatography, Gas/instrumentation , Chromatography, Gas/methods , Chromatography, Liquid , Dogs , Male , Nitrogen , PhosphorusABSTRACT
A sensitive and specific method for the determination of quinidine in plasma is described. Quinidine is extracted with chloroform, the extract is evaporated and reconstituted with methanol and the methanol extract is analyzed by high-performance liquid chromatography using a silica gel column. The recovery of quinidine from plasma varied between 93.0 to 100%. Quinidine levels as low as 12 ng/ml can be detected by this method.
Subject(s)
Quinidine/blood , Chromatography, Gas , Chromatography, High Pressure Liquid , Humans , Methods , Spectrometry, FluorescenceABSTRACT
A high-performance liquid chromatographic system using a silica gel column and methylene chloride:methanol:ammonium hydroxide as a solvent for the analysis of some drug substances is described. The procedure described is suitable for the analysis of pharmaceutical dosage forms.
