高效液相色谱法测定麻黄浸膏粉中麻黄类生物碱

采用高效液相色谱法分离了麻黄浸膏粉中去甲基麻黄碱、去甲基伪麻黄碱、麻黄碱、伪麻黄碱和甲基麻黄碱等 5种主要麻黄类生物碱。所用分离柱为HIQSILC18,流动相为含少量 (体积分数为 0 .2 % )甲醇的 0 .0 2mol L磷酸二氢钠溶液 (用HCl和三乙胺调至pH 3.2 )。 5种麻黄类生物碱在 2 5min内得到了有效分离、峰型对称且尖锐。     

Comparative study of some commercial chemically bonded phases in classical reversed-phase chromatography and in ion-pair reversed-phase liquid chromatography

Summary The behaviour of various octadecyl commercial bonded phases are compared in classical reversed-phase chromatography and in ion-pair reversed-phase chromatography. Great differences are exhibited by the packings studied according to the polarity of the solutes. Whereas hydrocarbonaceous bonded phases show very similar selectivity versus apolar or weakly polar solutes, great differences are observed when analyzing more polar solutes even when ion-pair reversed-phase chromatography is performed.Presented at the 14th International Symposium on Chromatography London, September, 1982     

The rapid quantitative analysis of codeine phosphate drug substance by reversed-phase high-performance liquid chromatography

Summary A rapid procedure for the evaluation of codeine phosphate drug substance derived from poppy straw or opium concentrate is described. The gradient HPLC procedure employs a pH 2.5 phosphate buffer, methanol and acetonitrile mobile phase at 40°C and a Bondapak C-18 column. Eight opium alkaloids, including the four major alkaloids, are separated from each other. The paper describes details of the assay procedure and presents data documenting the linearity, specificity, precision, and sensitivity of the method.     

Determination of the five major opium alkaloids by reversed-phase high-performance liquid chromatography on a base-deactivated stationary phase

Summary A reversed phase HPLC method for the separation of the five major alkaloids fromPapaver somniferum L., morphine, codeine, thebaine, papaverine and noscapine, has been developed and validated. By use of a basedeactivated silica-based stationary phase excellent peak shape was achieved for each substance. The five alkaloids were quantified by internal standardization within 20 min and with good precision. The method is applicable to opium and to poppy straw.     

Determination of ethambutol by ion-pair reversed phase liquid chromatography with UV detection

An ion-pair reversed phase liquid chromatography method for the antituberculosis drug ethambutol hydrochloride was developed using sodium 1-heptanesulfonate (4.0 mg/ml) as an ion-pairing (IP) reagent. To enable detection of the ethambutol with a UV detector without sample pretreatment, the pH 4.5 aqueous tetrahydrofuran (THF) (25%, v/v) mobile phase contained 1.0 mM Cu(II), which forms a UV-absorbing complex with the analyte. At a column temperature of 35 °C, ethambutol gives a symmetrical peak with a retention time of 5 min. Chromatographic conditions were optimized through study of the effects of mobile phase composition and pH, Cu(II) and IP reagent concentration, and column temperature. The method is shown to be simple, precise, efficient, robust, linear up to at least 0.25 mg/ml, and to have a limit of quantitation of 6 μg/ml.     

Separation of arsenic species by ion-pair and ion exchange high performance liquid chromatography

Arsenite, arsenate, monomethylarsonate, dimethylarsinate, arsenobetaine, arsenocholine and the tetramethylarsonium ion were subjected to ion-exchange and ion-pair reversed phase HPLC. The ion exchange method was superior in selectivity and time of analysis for the arsenic anions. The ammonium ions used for the ion-pair method only resulted in separation of some of the anionic arsenic compounds. Flame atomic absorption spectrometry was used for on-line arsenic-specific detection.     

Rapid separation of dinucleotides with ion-pair high performance liquid chromatography

Since 55-dinucleotides have been found in human organism, an increasing interest in separation methods of these compounds can be recognized. Their separation with conventional reversed-phase columns in the gradient elution mode affords more than 60 min. It has been demonstrated that an ion-pair reversed-phase HPLC based on perfusion chromatography achieves separation of dinucleotides within 10 min with high reproducibility, resolution and capacity.Presented as poster on the Analytica '94 in Munich, April 1994     

Principal opium alkaloids as possible biochemical markers for the source identification of Indian opium

A total of 124 opium samples originating from different licit opium growing divisions of India were analyzed for their principal alkaloid (thebaine, codeine, morphine, papaverine, and narcotine) content by capillary zone electrophoresis (CZE) without derivatization or purification. Absence of papaverine in Bareilly, Tilhar, and most of the samples originating from Kota is a significant observation in relation to the source of Indian opium. Multiple discriminant analysis was applied to the quantitative principal alkaloid data to determine an optimal classifier in order to evaluate the source of Indian opium. The predictive value based on the discriminant analysis was found to be 85% in relation to the source of opium and the study also revealed that all the principal alkaloids have to be analyzed for source identification of Indian opium. Chemometrics performed with principal alkaloids analytical data was used successfully in discriminating the licit opium growing divisions of India into three major groups, viz., group I, II, and III. The methodology developed may find wide forensic application in identifying the source of licit or illicit opium originating from India, and to differentiate it from opium originating from other opium producing countries.     

Rapid and sensitive determination of morphine in street opium samples by thermal desorption gas chromatography using a microfurnace pyrolyzer

Thermal desorption of the alkaloids in opium samples at 300 degrees C using a vertical microfurnace pyrolyzer was followed by their on-line gas chromatographic (GC) analysis on a large-bore glass capillary column. This method permitted rapid and sensitive determination of the content of the main alkaloid, morphine, in the small (ca. 100 microg) opium samples with a relative standard deviation within 4% for 5 runs. The observed morphine contents of about 12 to 15 w/w% in the given opium samples were in fairly good agreement with those estimated by a conventional GC-MS method.     

Quantitative analysis of total retronecine esters-type pyrrolizidine alkaloids in plant by high performance liquid chromatography

Pyrrolizidine alkaloids (PAs) are alkaloids which typically contain a necine (7-hydroxy-1-hydroxymethyl-6,7-dihydro-5H-pyrrolizidine) base unit, and they can be found in one third of the higher plants around the world. They are hepatotoxic, mutagenic and carcinogenic and pose a threat to human health and safety. A specific, quick and sensitive method is therefore needed to detect and quantify the PAs sometimes in trace amount in herbs, tea or food products. Based on high performance liquid chromatography with prior derivatization of the alkaloids using o-chloranil and Ehrlich's reagent, we report an improved method for quantitative analysis of the total amount of retronecine esters-type pyrrolizidine alkaloids (RET-PAs) in a plant extract. The total quantitation of RET-PAs is achieved because of a common colored retronecine marker, a 7-ethoxy-1-ethoxylmethyl retronecine derivative, is produced with all the different RET-PAs during the derivatization reaction. The chemical identity of the common retronecine marker was characterized on-line by positive mode electrospray ionization mass spectrometry and nuclear magnetic resonance spectroscopy. The limit of detection using the improved method is 0.26 nmol mL⁻¹ and the limit of quantitation is 0.79 nmol mL⁻¹. The advantages of this method are much enhanced sensitivity in detection and quantitation, and, no restriction on the choice of RET-PA as a calibration standard. Application of the developed method to the quantitation of total RET esters-type PAs in Senecio scandens from different regions of China is also reported.     

Reversed-phase thin-layer chromatography of 2-substituted benzoic acids with ammonium compounds as ion-pair reagents

Summary The retention behaviour of some substituted benzoic acids was tested on reversed-phase pre-coated plates in the presence of ammonium bromide and various tetraalkylammonium compounds with different alkyl chain lengths.It could be shown that the R_f values of the test compounds decrease in the absence and in the presence of ion-pair reagents with increasing water content of the eluent. The R_f values of the strongly acidic substituted benzoic acids decrease with both increasing concentration of the ion-pair reagent and with increasing chain length of the tetraalkylammonium compounds.Changing the inorganic counter-ions had no real influence on the separation and the size of R_f values when using tetramethylammonium compounds as ion-pair reagents.     

The challenges of the analysis of basic compounds by high performance liquid chromatography: Some possible approaches for improved separations

This review considers some of the difficulties encountered with the analysis of ionised bases using reversed-phase chromatography, such as detrimental interaction with column silanol groups, and overloading which both lead to poor peak shapes. Methods of overcoming these problems in reversed-phase (RP) separations, by judicious selection of the column and mobile phase conditions, are discussed. Hydrophilic interaction chromatography is considered as an alternative method for the separation of some basic compounds.     

Faster analysis by reversed-phase high-performance liquid chromatography

Summary Many analysts are not taking full advantage of the high speed possibilities of modern LC. Some analytical procedures reported in the literature, and many in regular use in control laboratories, could be achieved in less time without loss in precision. Some factors which affect retention times are discussed and the advantages and disadvantages of employing shorter column lengths and finer packing materials in reversed-phase HPLC are examined. The effect on efficiency of increased flow rates with 10,5 and 3 m ODS materials is shown. The ability to couple shorter column lengths without loss of efficiency is also demonstrated. This allows a minimum length to be selected that gives adequate resolution. Examples of high speed separations are shown and limitations in state of the art HPLC equipment and chromatographic data systems are discussed briefly.Presented at the 14th International Symposium on Chromatography London, September, 1982     

以离子液体作流动相添加剂的高效液相色谱法测定复方苦参注射液中4种生物碱

将离子液体1-丁基-3-甲基咪唑四氟硼酸盐(［BMIM］BF4)作为流动相添加剂建立了同时测定复方苦参注射液中4种主要生物碱的HPLC分析方法。以Agilent TC-C18柱(250 mm×4.6 mm, 5 μm)为分离柱,甲醇-0.1%磷酸水溶液(含2.2×10-4mol/L ［BMIM］BF4)(5:95, v/v)为流动相,流速1.0 mL/min,柱温30 ℃,进样量20 μL,在205 nm下检测。结果表明,苦参碱、槐定碱、氧化槐果碱以及氧化苦参碱的质量浓度分别在25.8～155.0 mg/L, 40.0～240.0 mg/L, 21.7～130.0 mg/L和37.5～225.0 mg/L范围内线性关系良好,相关系数均大于0.9990,平均回收率(n=9)在96.2%和98.9%之间。离子液体的加入能明显改善C18柱分离生物碱的色谱峰形并提高分离度。本法简便、快速、重复性好,可用于复方苦参注射液中生物碱的分离与测定。     

鸡蛋中三聚氰胺的液相色谱快速测定

建立了鸡蛋中三聚氰胺的液相色谱快速检测方法。样品经1%三氯乙酸溶液超声提取,磺基水杨酸和乙腈沉淀蛋白,高速离心分离,上清液过滤后直接由高效液相色谱分析。在优化的条件下,样品的色谱分析时间仅为10 min;三聚氰胺标准品在0.05～20 mg/L范围内,线性相关系数为0.9999;方法定量限为0.10 mg/kg (S/N＞10);1.0,2.0,4.0,6.0 mg/kg 4个加标水平测试,回收率在94.2%～107%之间;6次平行测试的相对标准偏差(RSD)为1.53%～2.06%。该方法前处理简单、分析速度快、灵敏度高,满足鸡蛋中三聚氰胺检验工作的快速测定要求。     

Rapid and simultaneous determination of imidazolium and pyridinium ionic liquid cations by ion-pair chromatography using a monolithic column

A method for rapid and simultaneous determination of imidazolium and pyridinium ionic liquid cations by ion-pair chromatography with ultraviolet detection was developed.Chromatographic separations were performed on a reversed-phase silica-based monolithic column using 1-heptanesulfonic acid sodium-acetonitrile as mobile phase.The effects of ion-pair reagent and acetonitrile concentration on retention of the cations were investigated.The retention times of the cations accord with carbon number rule.The method has been successfully applied to the determination of four ionic liquids synthesized by organic chemistry laboratory.     

Optimized ultrasound‐assisted extraction procedure for the analysis of opium alkaloids in papaver plants by cyclodextrin‐modified capillary electrophoresis

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.