Determination Of Codeine Research Articles

Extraction based on the flow-injection principle: Part 2. Determination of codeine as the picrate ion-pair in acetylsalicylic acid tablets

Codeine in aqueous samples is extracted as its picrate ion pair into chloroform in a continuous flow system. The sample is introduced into an aqueous picrate stream buffered at pH 6.5 ; its dispersion gives controlled mixing before the aqueous stream is segmented by a chloroform stream. A specially constructed fitting is included to produce segments, typically 5–10 mm long, which pass into a Teflon coil (2 m long; inner diameter, 0-8 mm). At the outlet of the coil. the phases are separated and a fraction of the chloroform phase is passed through a spectrophotometric flow cell. The sample volume is in the range 25–40 μl, the sampling rate about 60 h , and the relative standard deviation of the order of 1%.

PMR Assay of Natural Products in Pharmaceuticals. IV Assay of Codeine and Simultaneous Detection of Morphine

Abstract A rapid, accurate and precise PMR method is presented for the quantitative determination of codeine and codeine phosphate as bulk drugs and in tablet dosage form. The determination is based on the integration of the C-3 methylprotons or the two aromatic protons of codeine or its salt relative to that of the nine protons of t-butanol. Standard deviations of ± 1.39, 0.27 and 0.65% were obtained for codeine, codeine phosphate bulk drug and codeine phosphate tablets respectively. The method furnishes a specific means of identification of codeine as well as of the simultaneous detection and possible determination of morphine; thus fulfilling one of the most important pharmacopeial requirements for the purity of codeine.

Volumetric determination of codeine in the presence of morphine

Volumetric determination of codeine in the presence of morphine

Simultaneous determination of codeine and morphine in biological samples by gas chromatography with electron capture detection.

A sensitive gas chromatographic method for the simultaneous determination of codeine and morphine in plasma and brain samples is described. The method involves solvent extraction of the compounds from plasma, derivatization with pentafluoropropionic anhydride and subsequent separation on a 3% OV-17 column. The quantification is performed with electron capture detection. The sensitivity of the method (0.75 ng of morphine and 7.5 ng of codeine in a sample) makes it especially useful for pharmacokinetic investigations. The method was successfully applied to determine the time course of codeine and its metabolite morphine after intravenous administration of codeine to the rat.

Determination of nanogram amounts of aromatic compounds by spectrophotometry on thin-layer chromatograms

A highly sensitive method is described for the simultaneous determination of codeine and chlorpheniramine in plasma. Thin-layer chromatography is used for the separation of the drugs. The spots are then rendered visible by nitration of the substances on the thin-layer plate. Codeine can be quantified by direct measurement of the resulting fluorescence. After reduction, the aromatic amines are diazotized and coupled with N-(1-naphthyl)ethylenediamine on the thin-layer plate. For codeine the fluorimetric measurement is more reliable than the colorimetric determination. The sensitivity limits are 8 ng/ml of plasma for codeine phosphate and 1–2 ng/ml of plasma for chlorpheniramine maleate. This procedure is also applicable to other aromatic compounds which can be nitrated by the described method. The method has been applied to compare a determination of the plasma levels of codeine and chlorpheniramine after administration in normal capsules and retard tablets.

Quantitative GLC Determination of Codeine in Plasma

AbstractA sensitive and accurate GLC method for quantitating codeine in plasma at levels of 50 ng/ml, with limits of detection as low as 5 ng/ml, is described.

Gas-Chromatographic Measurement of Codeine and Norcodeine in Human Plasma

A gas-chromatographic method is described for determination of codeine and norcodeine in human plasma. The method is specific, sensitive, and precise. It was developed for use in bioavailability studies of therapeutic doses of codeine sulfate. After ingestion of a 60-mg codeine sulfate tablet, mean peak codeine concentration in plasma was 107 mug/liter at 1.0 hour. No measurable concentration of norcodeine was found in the plasma by this method.

A rapid g.l.c. procedure for the determination of codeine and norcodeine in biological fluids based on micro-phase extraction techniques.

Therapeutic serum concentrations of codeine can be virtually completely extracted and obtained sufficiently concentrated for g.c. measurement without distillation, by acid extraction of the drug from the initial crude organic extracts of alkalinized serum followed by a micro-phase back extraction step. The procedure has simplicity, rapidity and eliminates concentration by distillation and background interference. The method can be readily adapted for the seperate measurements of codeine and norcodeine and it can also be used for similar analysis of other body fluids.

Gas Chromatographic Determination of Codeine in Serum and Urine

A method for gas chromatographic detection of codeine in serum is described. An application to a clinical drug evaluation study is given. A method for simultaneous detection of free and total codeine and its metabolites, norcodeine and morphine, in urine is also presented.

The Determination of Codeine in Mixtures with Antihistamines

The Determination of Codeine in Mixtures with Antihistamines

アヘンアルカロイドの分析研究 (第11報)

Oxidation of codeine and morphine with ceric ammonium nitrate and application of 2, 4-dinitrophenylhydrazine results in orange-red coloration. Thebaine, narcotine, and papaverine color yellowish to this reaction and can therefore be discriminated from the former two. Limit of detection is 1.5γ/0.05cc. In quantitative determination, interfering thebaine, narcotise, and papaverine must be removed. The procedure for determination of codeine is as follows: One cc. of aqueous solution of codeine (30-240 γ/cc.) is placed in a 5-cc. measuring flask, 2cc. of water is added, and the mixture is allowed to stand in crushed ice (0 to 2°) for 5 minutes. To this solution, 1cc. of 0.6% ceric ammonium nitrate (in N sulfuric acid), which had been stood in crushed ice for 5 minutes, is added, mixed well, and allowed to stand at that temperature for 25 minutes. To this mixture, 0.5cc. of 0.6% 2, 4-dinitrophenylhydrazine solution is added, the flask is removed from the ice bath, and allowed to stand at room temperature for 20 minutes. The mixture is diluted to 5cc. with water, shaken well, and transferred to a glass-stoppered centrifuge tube. Ten cc. of isoamyl acetate is added to the tube, shaken 100 times, and centrifuged for 3 minutes. Isoamyl acetate layer is discarded, 5cc. of fresh isoamyl acetate is added, and treated in the same manner. Absorbancy of the aqueous layer is measured at 500mμ. A blank test is carried out with the same reagent and in the same manner, using 1cc. of water in place of the test solution, and used as the control.In the presence of thebaine, the test solution is heated with N hydrochloric acid, basified with sodium hydroxide, and shaken with chloroform to transfer codeine into the chloroform layer.In the presence of narcotine and papaverine, the test sample is dissolved in 0.2% tartaric acid, shaken with chloroform, and the aqueous layer is submitted to determination of codeine as above.

Chromatographic Determination of Codeine in Opium and Other Complex Mixtures

Chromatographic Determination of Codeine in Opium and Other Complex Mixtures