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1.
This study investigated the use of ultrasound‐assisted extraction to improve the extraction efficiency of morphine, codeine and thebaine from the papaver plants. Extraction conditions such as type of solvent, temperature, duration, frequency and power level of ultrasonic were optimized and the influences of different parameters on resolution of alkaloids in CE were studied. The optimized condition for CE separation includes a sodium phosphate buffer (100 mM, pH 3.0) containing 5 mM α‐CD. The optimized extraction conditions for ultrasound‐assisted extraction was an extraction time of 1 h, an ultrasonic frequency of 60 kHz with water–methanol (80:20) at 40°C as the extraction solvent. The LOD for alkaloids was found to be 0.1 μg/mL at a signal‐to‐noise ratio of 3:1. The RSDs for peak areas were in the range of 1.4–4.4%. The amounts of opium alkaloids (mg/100 g dried sample) in four Iranian papaver plants were found to be in the range of 7.8–8.7 (morphine), 5.5–9.5 (codeine) and 1.4–10.4 (thebaine). It should be emphasized that no cleanup of the filtered extract was required; hence, direct determination after extraction drastically simplifies the analytical process.  相似文献   
2.
Zhou S  Tan J  Chen Q  Lin X  Lü H  Xie Z 《Journal of chromatography. A》2010,1217(52):8346-8351
A novel open tubular (OT) column covalently modified with hydrophilic polysaccharide, carboxymethylchitosan (CMC) as stationary phase has been developed, and employed for the separations of basic proteins and opium alkaloids by capillary electrochromatography (CEC). With the procedures including the silanization of 3-aminopropyltrimethoxysilane (APTS) and the combination of glutaraldehyde with amino-silylated silica surface and CMC, CMC was covalently bonded on the capillary inner wall and exhibited a remarkable tolerance and chemical stability against 0.1 mol/L HCl, 0.1 mol/L NaOH or some organic solvents. By varying the pH values of running buffer, a cathodic or anodic EOF could be gained in CMC modified column. With anodic EOF mode (pH<4.3), favorable separations of basic proteins (trypsin, ribonuclease A, lysozyme and cytochrome C) were successfully achieved with high column efficiencies ranging from 97,000 to 182,000 plates/m, and the undesired adsorptions of basic proteins on the inter-wall of capillary could be avoided. Good repeatability was gained with RSD of the migration time less than 1.3% for run-to-run (n=5) and less than 3.2% for day-to-day (n=3), RSD of peak area was less than 5.6% for run-to-run (n=5) and less than 8.8% for day-to-day (n=3). With cathodic EOF mode (pH>4.3), four opium alkaloids were also baseline separated in phosphate buffer (50 mmol/L, pH 6.0) with column efficiencies ranging from 92,000 to 132,000 plates/m. CMC-bonded OT capillary column might be used as an alternative medium for the further analysis of basic proteins and alkaline analytes.  相似文献   
3.
The application of micellar electrokinetic capillary chromatography (MECC) to the analysis of illicit drug seizures is presented. Areas investigated include general screening and qualitative and, in some instances, quantitative analysis of various drugs, including heroin, opium, cocaine, amphetamines, LSD and anabolic steroids. Due to its high efficiency, high selectivity and general applicability, MECC is well suited for forensic drug analyses.  相似文献   
4.
Opium samples from four different locations and poppy straw from different plant varieties have been assayed using micellar capillary electrophoresis incorporating a sweeping technique. Individual alkaloids (morphine, codeine, papaverine, noscapine, thebaine, oripavine, reticuline and narceine) were quantitatively determined in the different samples by a validated capillary electrophoresis method. Unsupervised pattern recognition of the opium samples and the poppy straw samples using hierarchical cluster analysis (HCA) and principal component analysis (PCA), showed distinct clusters. Supervised pattern recognition using soft independent modelling of class analogy (SIMCA) was performed to show individual groupings and allow unknown samples to be classified according to the models built using the CZE assay results.  相似文献   
5.
鸦片的气相色谱快速分析   总被引:2,自引:0,他引:2  
采用大口径毛细管柱,建立了一种气相色谱测定鸦片中生物碱的快速分析方法。样品经超声提取,HP-1(5m×0.53mm×2.65μm)毛细管色谱柱,FID测定。回收率为96.8% ̄101.1%,相对标准偏差均小于3%。方法简便,快速,准确,灵敏。  相似文献   
6.
A new procedure for the rapid analysis of four major opium alkaloids is described using ion-pair, reversedphase high performance liquid chromatography and recently developed radial compression column technology. The solvents were aqueous 10mM potassium perchlorate with 5.0mM n-butylamine (pH 3.0) and pure acetonitrile. A gradient was run for five minutes from 10% to 70% acetonitrile and held at that level for two minutes. Flow rates were 3 ml/min. Two column packing materials were compared with this solvent system: standard C-18 packing and a fully-end-capped C-18 material. Results obtained with the fully-end-capped C-18 packing and the two solvent ion-pair gradient showed elution times under six minutes, with greater sensitivity (<50 nanograms) than previous systems.  相似文献   
7.
Neopine, a minor opium alkaloid and an isomer of codeine (also known as -codeine), has been detected in both the urine of opium users and pharmaceutical codeine users. The characterization of neopine was achieved by comparison of the mass spectra and GC retention times of the trimethylsilyl derivative. The presence of neopine in the urine of pharmaceutical codeine users was attributed to the metabolism of codeine through a double bond migration in ring C, from the 7–8 to the 8–14 position. The potential use of the alkaloid as a confirmation marker of opium and/or pharmaceutical codeine use and the ability to differentiate these from heroin use has been discussed.  相似文献   
8.
We describe the use of capillary zone electrophoresis (CZE) for the qualitative and quantitative determination of major alkaloids (i.e., thebaine, codeine, morphine, papavarine and narcotine) in gum opium involving the analysis of alkaloids without derivatization or purification. Three extractions with 2.5% w/v aqueous acetic acid quantitatively extracted major alkaloids. The separation was carried out by CZE using a 7:3 mixture of methanol and sodium acetate (100 mM, pH 3.1) at a potential of 15 kV, with UV detection at 224 nm. Spiking of pure reference alkaloid standards in the opium extract was used for peak identification. The influences of buffer composition, pH and voltage on the separation of alkaloids were studied. The detection limit of each alkaloid dissolved in methanol was found to be 850 ng/mL (morphine), 450 ng/mL (thebaine), 500 ng/mL (codeine), 550 ng/mL (papaverine), and 500 ng/mL (narcotine) at an injection pressure of 300 mbar (injection volume, 4 nL) with a signal-to-noise ratio of 3:1. The external standard method was used for the quantification of alkaloids. The calibration plot was based on linear regression analysis. The relative standard deviation (RSD) for peak area and migration time was in the range of 1.03-3.56% and 0.34-0.69%, respectively. Percentage compositions (g%) of opium alkaloids in five gum opium samples were found to be in the range of 14.45-15.95 (morphine), 2.0-3.45 (codeine), 1.32-2.73 (thebaine), 0.92-2.37 (papavarine), and 3.85-5.77 (narcotine). The method developed is suitable for the routine analysis of major gum opium alkaloids in samples of forensic importance.  相似文献   
9.
10.
Cationic and non‐ionic surfactant mediated systems have been studied as mobile phases in thin chromatographic studies of opium alkaloids on silica gel G. The effect of surfactant concentration below and above its critical micellar concentration on the mobility of alkaloids was examined. The influence of different alcohols (methanol, ethanol, propanol and butanol) in micellar solutions on the mobility and separation efficiency of alkaloids was assessed. The technique has also been applied for semiquantitative determination of codeine sulphate (2.5–35 μg) and papaverine. HCl (2.5–30 μg) in mixtures as well as in pharmaceuticals. The lower limits of detection of papaverine. HCl and codeine sulphate were 1.0 μg and 1.5 μg, respectively.  相似文献   
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