环境和生物样品中有机氯农药残留检测研究进展

综述了环境和生物样品中有机氯农药残留检测中样品的前处理方法(包括溶剂提取、溶剂提取和层析柱分离法、微波萃取、凝胶渗透色谱净化法、固相萃取法等)和测定方法(包括气相色谱法、气相色谱-质谱法等)的研究进展。     

气相色谱法测定硫酸麻黄碱中的甲苯残留量

有机溶剂残留量是评价药品质量的一项重要指标。甲苯为原料药硫酸麻黄碱合成中引入的对人体有害的有机溶剂，根据ICH及中国药典有关规定，甲苯残留量不得超过0．0089％。对药品中残留有机溶剂的测定，大多采用气相色谱法，但有关原料药硫酸麻黄碱中甲苯残留量的测定，未见文献报道。笔者建立了硫酸麻黄碱中甲苯残留量的气相色谱分析方法，方法简便，测定结果准确。     

顶空色谱法测定食品添加剂中的残留溶剂

食品添加剂在合成和后处理过程中常用有机溶剂.需对其进行定量测定。一般食品添加剂的分子量大,挥发性小,对其中所残留的微量挥发性溶剂的测定用顶空色谱法(HSGC)是最简便和有效的。本方法是测定食品添加剂中残留的乙酸乙酯。固体样品溶于四氢呋喃(THF)—水混合溶剂中。OV-17毛细管柱分离。内加法定量,利用THF中与乙酸乙酯相邻,含量相近的杂质峰作参     

加压流体萃取–气相色谱法测定土壤中丙烯酸

建立加压流体萃取–气相色谱法测定土壤中丙烯酸含量的方法.将处理后的土壤样品加入至密闭容器中,采用丙酮作为溶剂,在压力为8.27～13.79 MPa,温度为100℃的条件下,液态的有机溶剂与土壤样品充分接触,将土壤中有机物提取到有机溶剂中.提取液经凝胶渗透色谱净化、浓缩、定容,用气相色谱分离,根据保留时间进行定性,以色谱...     

超声波溶剂提取-气相色谱法测定烟草及烟草制品中19种有机氯农药残留

建立了超声波溶剂提取-气相色谱法同时测定烟草及其制品中19种有机氯农药残留。样品采用正己烷-丙酮超声提取,经Florisil固相萃取柱净化后,采用气相色谱-电子捕获检测法(GC-ECD)进行检测。结果发现,19种有机氯农药加标回收率均在72%以上,相对标准偏差(RSD)在0.1%～9.0%,能满足当前烟草中有机氯农药残留的同时快速检测要求。     

加参片中大孔树脂有机残留溶剂的顶空-气相色谱法测定

运用顶空-气相色谱法在同一色谱条件下以乙苯为内标测定了中药复方制剂加参片中可能存在的正己烷、苯、正癸烷、甲苯、二甲苯(对、间、邻)、苯乙烯等8种大孔树脂残留溶剂,为大孔树脂的安全应用提供保证.在设定的顶空-气相条件下,各待测残留物与复方制剂中的其它成分分离良好,在考察的浓度范围内线性关系良好(r=0.9966～0.9998),加样回收率92.05%～112.46%,精密度0.7%～5.8%,各溶剂检测限满足残留溶剂的限度要求.结果表明,使用净品级大孔树脂,能够简化预处理工作,经其提取纯化制得的3批成品中,各残留溶剂均未检出,符合限度要求.该方法适用于中药复方制剂加参片中大孔树脂残留溶剂的控制.此外,本研究对色谱条件、顶空条件进行了探讨.     

顶空-气相色谱法测定枳实总黄酮提取物中的树脂残留和溶剂残留

<正>枳实总黄酮提取物是临床上用于治疗功能性消化不良的中药在研1类新药奥兰替胃康片的原料^[1-4]，其制备过程中用乙醇提取，并使用了D101大孔吸附树脂纯化黄酮提取物。提取物及相关制剂的质量标准研究主要包括含量测定、特征图谱、溶出度等^[5-8]，尚无残留溶剂研究的相关报道；另从药品安全性角度考虑，根据《中药新药质量研究技术指导原则(试行)》和《中华人民共和国药典》2020年版(简称ChP 2020)四部通则0861残留溶剂测定法的要求，应对提取加工过程中引入的树脂残留、有机溶剂等进行控制。参考ChP 2020一部三七总皂苷等的树脂残留方法进行优化，本工作采用顶空-气相色谱法对枳实总黄酮提取物中树脂残留(正己烷、苯、甲苯、乙苯、对二甲苯、间二甲苯、邻二甲苯、苯乙烯、二乙烯苯等9种成分)以及溶剂残留(乙醇)进行测定。     

顶空气相色谱法测定食品添加剂中15种有机溶剂残留量

建立了顶空气相色谱法同时测定食品添加剂中甲苯、甲醇、正己烷等15种有机溶剂残留量的分析方法。选择N,N-二甲基甲酰胺对不同食品添加剂中的有机溶剂进行提取,将样液转移至顶空瓶中密封,顶空进样测定。对提取溶剂、提取方式、平衡时间和平衡温度等进行了优化。结果表明,15种有机溶剂分离良好,各残留溶剂在相应浓度范围内呈良好的线性关系,相关系数不小于0.999 8,定量下限为10.0 mg/kg(三氯甲烷和吡啶为20.0 mg/kg),回收率为90.6%~109.1%,相对标准偏差为0.1%~7.2%。该方法灵敏度高,重现性好,适用于食品添加剂中甲苯、甲醇、正己烷等15种残留溶剂的检测分析。     

8种农药的大口径毛细管气相色谱分析

1　引　　言2 0世纪 80年代 ,毛细管气相色谱 (CGC)技术就广泛用于农药残留分析。现在毛细管气相色谱与固相萃取、固相微萃取、质谱等技术一起 ,被广泛地应用于农药的多残留分析。但作为农药原药和制剂的有效成分的常规分析 ,直至进入2 0世纪 90年代后才在农药国际标准分析方法 (CIPAC)手册中相继出现。近年来 ,随着大口径毛细管推广应用和一些重大技术的改进 ,毛细管气相色谱作为农药的常规分析方法 ,发展比较快。到目前为止 ,CIPAC已经建立了近 2 0个农药原药及其制剂的毛细管气相色谱标准分析方法。大口径毛细管气相色谱法具有分析…     

气相色谱法测定爱普列特原料药中的残留溶媒

建立了气相色谱法测定爱普列特中的残留溶剂含量的方法。采用HP-FFAP毛细管色谱柱(30m×0.53mm×1.0μm),氢火焰离子化检测器(FID),程序升温进行测定。9种残留溶剂均完全分离,在考察的浓度范围内线性关系良好(r大于0.999),回收率符合规定。该气相色谱方法准确,灵敏度高,可用于爱普列特中残留溶剂的质量控制。     

Preparation,evaluation, and comparison of wide bore (320 μm) and narrow bore (50 μm) cyanosilicone-coated capillary columns for gas chromatography

The preparation of wide bore (320 μm) and narrow bore (50 μm) fused silica capillary columns is described for immobilized cyanopropyl substituted silicones containing 60 and 88% substitution. The effect of high temperature deactivation with cyanopropylcyclosiloxanes was studied with a special test mixture. Curing was achieved with dicumyl peroxide or azo-tert-butane. The columns were evaluated and compared in terms of efficiency, activity, polarity, and temperature stability. Different coating methods were compared for the narrow bore columns. The activity of the 60% cyanopropyl columns that had been immobilized with dicumyl peroxide was significantly larger than for azo-tert-butane immobilized columns. The polarity of polar columns appeared to depend greatly on column temperature and is completely different for wide and narrow bore columns.     

Application of the solvation parameter model in method development for analysis of residual solvents in pharmaceuticals

The solvation parameter model was applied in the development of a method for the analysis of residual solvents in pharmaceuticals. The interactions between organic solvents and six different stationary phases were studied using gas chromatography. The retention times of the organic solvents on these columns could be predicted under isothermal or temperature-programmed conditions using the established solvation parameter models. The predicted retention times helped in column selection and in optimizing chromatographic conditions during method development, and will form the basis for the development of a computer-aided method.     

Preliminary identification and quantification of residual solvents in pharmaceuticals using the parallel dual-column system

A database for preliminary identification and quantification of residual solvents in pharmaceuticals has been established using the parallel dual-column system. Two columns with different polarities, SPB-1 and HP-INNOWAX, connected with a 'Y' splitter, constituted the dual pathways system. Fifty-two solvents were studied according to the guidelines for residual solvents regulated by the International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) on this system. Through a single run, preliminary identification and quantification can be performed using the database. An important advantage of the database is that the residual solvents in the pharmaceuticals can be prescreened without using reference organic solvents.     

Enhancing Metal Separations by Liquid–Liquid Extraction Using Polar Solvents

The less polar phase of liquid–liquid extraction systems has been studied extensively for improving metal separations; however, the role of the more polar phase has been overlooked for far too long. Herein, we investigate the extraction of metals from a variety of polar solvents and demonstrate that, the influence of polar solvents on metal extraction is so significant that extraction of many metals can be largely tuned, and the metal separations can be significantly enhanced by selecting suitable polar solvents. Furthermore, a mechanism on how the polar solvents affect metal extraction is proposed based on comprehensive characterizations. The method of using suitable polar solvents in liquid–liquid extraction paves a new and versatile way to enhance metal separations.     

Naphthalene sulphonic acids--new test compounds for characterization of the columns for reversed-phase chromatography

Non-substituted naphthalene sulphonic acids are strong acids, which are completely ionised in aqueous and aqueous-organic solutions. Because of repulsive electrostatic interactions, they are more or less excluded from the pores of the column packing materials commonly used in reversed-phase chromatography. The ionic exclusion can be suppressed by increasing the ionic strength of the mobile phase. In aqueous sodium sulphate solutions, very good selectivity was observed for isomeric naphthalene di- and tri-sulphonic acids, allowing reversed-phase separations of these strongly ionic compounds without addition of ion-pairing reagents to the mobile phase. The retention of the isomeric acids increases proportionally to the dipole moment, which can be explained by its effect on increasing exposure of the naphthalene ring to hydrophobic interactions with the non-polar stationary phases. Chromatographic behaviour of isomeric naphthalene di- and trisulphonic acids was investigated on 25 different columns for reversed-phase chromatography. The elution order of the isomers is the same on all the columns, but very strong stationary phase effects were observed on the retention and on the band asymmetry, depending on polar interactions with residual silanol groups and other polar adsorption centres in the stationary phases. These effects are independent of the organic solvents, as the tests are performed in purely aqueous mobile phases and allow classification of the columns into several groups.     

Stabilization of proteases by entrapment in a new composite hydrogel

A new one-step procedure for entrapping proteases into a polymeric composite calcium alginate-poly(N-vinyl caproladam) hydrogel was developed that provided 75–90% retention of the activity of entrapped enzymes compared to soluble ones. Properties of entrapped carboxypeptidase B, trypsin, and thrombin were investigated. The immobilized enzymes were active within a wide pH range. The temperature optima of entrapped trypsin and carboxypeptidase B were approx 25°C higher than that of the soluble enzymes, and the resistance to heating was also increased. The effects of various polar and nonpolar organic solvents on the entrapped proteases were investigated. The immobilized enzymes retained their activity within a wide concentration range (up to 90%) of organic solvents. Gel-entrapped trypsin and carboxypeptidase (CPB) were successfully used for obtaining human insulin from recombinant proinsulin. The developed stabilization method can be used to catalyze various reactions proceeding within wide pH and temperature ranges.     

Safer solvents for reactive organometallic reagents

This paper describes the use of poly(α -olefin)s (PAOs) as safer alternatives to cyclohexane, hexanes, and heptane as solvents for alkyllithium reagents. While PAOs like any alkane are flammable, PAOs do not readily catch on fire because they contain 20 or more carbon atoms, a low volatility, and have a high flash point vis-à-vis alkanes like hexane. Also unlike conventional alkanes, PAOs can be quantitatively separated from polar organic solvents and polar organic products either by a simple gravity separation or by an extraction after a reaction. Any leaching of the PAO solvent into a polar phase during such a separation can be minimized by addition of small amounts of water to the polar phase. However, while these PAO solvents have some physical differences from conventional low molecular weight volatile alkanes, they otherwise behave like alkanes and alkyllithium reagents in these PAO solvents can used in their conventional reactions in these PAO solvents.     

Stationary and mobile phases in hydrophilic interaction chromatography: a review

Hydrophilic interaction chromatography (HILIC) is valuable alternative to reversed-phase liquid chromatography separations of polar, weakly acidic or basic samples. In principle, this separation mode can be characterized as normal-phase chromatography on polar columns in aqueous-organic mobile phases rich in organic solvents (usually acetonitrile). Highly organic HILIC mobile phases usually enhance ionization in the electrospray ion source of a mass spectrometer, in comparison to mobile phases with higher concentrations of water generally used in reversed-phase (RP) LC separations of polar or ionic compounds, which is another reason for increasing popularity of this technique. Various columns can be used in the HILIC mode for separations of peptides, proteins, oligosaccharides, drugs, metabolites and various natural compounds: bare silica gel, silica-based amino-, amido-, cyano-, carbamate-, diol-, polyol-, zwitterionic sulfobetaine, or poly(2-sulphoethyl aspartamide) and other polar stationary phases chemically bonded on silica gel support, but also ion exchangers or zwitterionic materials showing combined HILIC-ion interaction retention mechanism. Some stationary phases are designed to enhance the mixed-mode retention character. Many polar columns show some contributions of reversed phase (hydrophobic) separation mechanism, depending on the composition of the mobile phase, which can be tuned to suit specific separation problems. Because the separation selectivity in the HILIC mode is complementary to that in reversed-phase and other modes, combinations of the HILIC, RP and other systems are attractive for two-dimensional applications. This review deals with recent advances in the development of HILIC phase separation systems with special attention to the properties of stationary phases. The effects of the mobile phase, of sample structure and of temperature on separation are addressed, too.     

Extraction of organic compounds with room temperature ionic liquids

Room temperature ionic liquids are novel solvents with a rather specific blend of physical and solution properties that makes them of interest for applications in separation science. They are good solvents for a wide range of compounds in which they behave as polar solvents. Their physical properties of note that distinguish them from conventional organic solvents are a negligible vapor pressure, high thermal stability, and relatively high viscosity. They can form biphasic systems with water or low polarity organic solvents and gases suitable for use in liquid–liquid and gas–liquid partition systems. An analysis of partition coefficients for varied compounds in these systems allows characterization of solvent selectivity using the solvation parameter model, which together with spectroscopic studies of solvent effects on probe substances, results in a detailed picture of solvent behavior. These studies indicate that the solution properties of ionic liquids are similar to those of polar organic solvents. Practical applications of ionic liquids in sample preparation include extractive distillation, aqueous biphasic systems, liquid–liquid extraction, liquid-phase microextraction, supported liquid membrane extraction, matrix solvents for headspace analysis, and micellar extraction. The specific advantages and limitations of ionic liquids in these studies is discussed with a view to defining future uses and the need not to neglect the identification of new room temperature ionic liquids with physical and solution properties tailored to the needs of specific sample preparation techniques. The defining feature of the special nature of ionic liquids is not their solution or physical properties viewed separately but their unique combinations when taken together compared with traditional organic solvents.     

Estimation of Residual Nickel and Some Heavy Metals in Vanaspati Ghee

To convert vegetable edible oils into vanaspati ghee, nickel is used as a catalyst in the hydrogenation process. A simple and fast method for the trace level determination of nickel in ghee is reported. In this work different methods were applied for the extraction of residual nickel from ghee samples. Using toluene, benzene and carbon tetrachloride as organic solvents, an acid mixture was used for the extraction of nickel. Extracted nickel was quantified with atomic absorption and colorimetric methods. Among the organic solvents, toluene proved to be the best solvent mediating a 95% extraction of nickel from ghee samples. Nickel was extracted and determined in ten different brands of ghee and in all samples its amount was well above the permissible limit of WHO (0.2 μg/g). Other metals like lead, zinc, copper, and cadmium were also determined and their concentrations were found to be much below the WHO permissible limits.