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为准确测定烟草浸膏中烟碱含量,以2-甲基喹啉为内标建立了测定烟草浸膏中烟碱的气相色谱-氢火焰离子化法(GC-FID),并测定了5个烟草浸膏样品.结果表明,方法的回收率为95.00%~98.58%,检出限为0.27 mg/g,定量限为0.89 mg/g.所测烟草浸膏中烟碱的质量分数在19.66~54.97 mg/g之间.方法简单、灵敏、准确,适用于烟草浸膏中烟碱的测定. 相似文献
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陈安诺李笑文王欣怡叶小青 《化学分析计量》2023,(4):93-101
综述了环境介质与生物样品中三氯生残留的检测方法研究进展。检测方法有气相色谱-质谱法、液相色谱法、液相色谱-质谱联用以及分光光度法、酶联免疫分析方法和电化学法等。气相色谱-质谱法检测三氯生线性关系良好,检出限、定量限低,精密度、准确度较高,但样品需要衍生化前处理,操作较为复杂。液相色谱法操作相对于气相色谱-质谱法更为简便,且具有选择性强、线性范围宽、定量准确和精密度高等优点,目前高效液相色谱法是大多数实验室的首选。液相色谱-质谱法是在液相色谱的基础上,采用质谱法对样品中的三氯生残留进行定性定量,定量准确,检出限低。其他方法的使用率较低,但也可满足环境介质与生物样品中三氯生残留的检测。目前乃至未来的一段时间内,环境介质及生物样品中三氯生残留的检测方法将以色谱-质谱法为主。目前仪器检测技术条件已经相对成熟,因此应积极寻找适合不同样品的前处理方法,使检测结果更加准确和精确,实验过程更加快捷方便。 相似文献
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提出了亲水作用-高效液相色谱法测定不同烟草部位中烟碱含量的方法。采用Atlantis HILIC色谱柱(150mm×4.6mm,5μm)分离,以乙腈、10mmol·L-1乙酸铵溶液和冰乙酸以体积比72比28比2组成的混合液为流动相,在检测波长260nm处进行测定。烟碱的质量浓度在0.001~0.1g·L-1范围内与峰面积呈线性关系,方法检出限(3S/N)为0.17mg·L-1。进行3个浓度水平的加标回收试验,测得回收率在98.2%~98.9%之间,相对标准偏差(n=6)小于2.0%。从烟草的不同部位取样,按本法分析,结果表明:其烟碱含量从烟叶的上部、中部、下部至烟梗逐渐减少。 相似文献
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液化气中元素硫的高效液相色谱法分析 总被引:6,自引:0,他引:6
应用溶剂萃取、冷却气化方法对液化气样品进行前处理。对前处理制备的样品使用高效液相色谱法进行测定,以甲醇/水=95/5(V/V)为流动相,紫外检测(254nm),在C18柱上成功地分离并测定了元素硫的含量。方法检测限为0.1ng/g,有良好的准确度与精密度,能充分满足各种液化气中元素硫的测定需要。 相似文献
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乳制品中的有害物质包括农兽药残留、毒素残留、重金属残留、微生物、有害添加剂以及在包装或运输过程引入的有害物等,对人的健康存在较大危害,开发乳制品中有害物质的高效灵敏分析检测方法具有重要的经济和社会效益。但乳制品样品种类多、基质复杂,有害物质结构和性质差异大、含量水平低,需要发展快速高效的样品前处理技术和准确灵敏的分析检测方法。该文综述了近十年来乳制品样品前处理方法的研究进展,包括液相(微)萃取法、固相(微)萃取法、免疫亲和色谱法等。介绍了各类有害物质的分析检测技术如色谱法、原子光谱法、电化学分析法、生物免疫法、分子光谱法等的研究进展,重点比较了实验室分析方法与现场快速检测方法的优势与不足。最后,全面总结了这些技术的特点并展望了其发展趋势,以期为我国乳制品质量安全监管提供支持。 相似文献
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Summary Different sampling and analysis techniques for the determination of gas-phase nicotine and 3-ethenylpyridine in environmental tobacco smoke are reported. Graphitized carbon traps, annular diffusion denuders, and nebulizer collectors have been used as sampling devices in combination with either thermal desorption or with water extraction. Capillary gas chromatography and ion-pair reversed-phase chromatography were applied to desorbed and liquid samples obtained in an intercomparison indoor study. The methods developed here show some advantages over existing methods in terms of analysis time, sensitivity and loading capacity. 相似文献
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《Journal of separation science》2003,26(17):1554-1562
An off‐line high‐performance normal‐phase liquid chromatography procedure with a silica column followed by reversed‐phase high‐performance liquid chromatography (HPLC) with fluorescence detection for the determination of polycyclic aromatic hydrocarbons (PAHs) in edible oils is reported. The method was validated using certified reference materials and compared with a standardized method widely used in the food industry, consisting in low pressure column chromatography with alumina as stationary phase followed by reversed phase HPLC determination. The limits of detection were lower than 1 ng/g and good selectivity was achieved for both methods. There were no significant differences in accuracies and precisions obtained for each approach. The advantages and disadvantages of the two methods are discussed. 相似文献
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H. Tang G. Richards K. Gunther J. Crawford M. L. Lee E. A. Lewis D. J. Eatough 《Journal of separation science》1988,11(11):775-782
A combined sampling and analysis technique for the determination of gas phase nicotine and 3-ethenylpyridine, and of particulate phase nicotine in environmental tobacco smoke with capillary gas chromatography is reported. The major advantage of the technique is that all of the collected particulate phase material is analyzed by thermal desorption of the collected material rather than by analysis of only a fraction of the sample extracted from the collection medium. A Teflon filter microtube is used to collect particulate phase nicotine. This microtube is follwed by a small Tenax sorbent bed to collect gas phase nicotine and 3-ethenylpyridine. After sampling, the Teflon filter is transferred to a clean glass tube and the tube becomes an insert for a modified packed column injector port where the material collected on the filter is heat desorbed to a cold capillary tubing trap. Gas phase nicotine and 3-ethenylpyridine are also transferred from the Tenax to the GC column by thermal desorption from the Tenax sorbent bed. Gas phase nicotine and 3-ethenylpyridine, and particulate phase nicotine are each determined by GC analysis of the desorbed material. Nicotine and 3-ethenylpyridine are quantitated by the use of external standards. This technique is straightforward and can be used for semi-real time determination of both gas and particulate phase compounds in environmental tobacco smoke. The results obtained by this technique compare well with those obtained by sampling with annular diffusion denuders. 相似文献
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Valfredo Azevedo Lemos Elenir Souza Santos Moacy Selis Santos Regina Terumi Yamaki 《Mikrochimica acta》2007,158(3-4):189-204
An overview is presented on thiazolylazo dyes and their analytical applications in the determination, preconcentration or
separation of trace metal ions. The article summarizes conventional analytical methods based on spectrophotometry, solid phase
extraction, liquid chromatography and liquid–liquid and cloud point extraction. Both in-batch and on-line procedures are considered.
General properties about these ligands are also commented on. Finally, the use of thiazolylazo dyes in procedures involving
electroanalytical and other methods is presented. 相似文献
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环境中氯苯类化合物的分析研究进展 总被引:1,自引:0,他引:1
氯苯类化合物(邻二氯苯、对二氯苯、间二氯苯、三氯苯、氯甲苯、二氯甲苯和三氯甲苯等)是环境中需要重点监测的致癌污染物,文章介绍了近年来国内外环境中氯苯类化合物的分析研究进展。主要的分析测定方法有:普通气相色谱法、固相微萃取.毛细管气相色谱法、吹扫捕集.气相色谱法、顶空气相色谱法、高效液相色谱法、光度法和红外光谱法等。分析测定方法和结果对评价环境污染具有重要意义。 相似文献
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《液相色谱法及相关技术杂志》2012,35(11):2375-2389
Abstract A new procedure has been developed to measure nicotine in blood plasma by high-performance liquid chromatography (HPLC). Nicotine is extracted from plasma by elution with cholorform. Final determination is achieved by isocratic HPLC with ultraviolet detection. Twenty microliters of plasma extract is deluted over a silica column at a flow rate of 1.0 ml/min with a dioxane:isopropanol:NH4OH (80:3.0:0.4) mobile phase. The procedure is sensitive to 0.05 ug of nicotine per ml of plasma and is linear within the range of 0.05 to 10.0 ug/ml of plasma. When a known amount of nicotine was added to plasma, the concentration of nicotine measured averaged 99.9 + 3.9 (S.D.)% of the known concentration. The within-sample coefficient of variation was 3.9% 相似文献
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The determination of nicotine and cotinine by ion pair reversed-phase chromatography 总被引:1,自引:0,他引:1
L J Lewis J D Lamb D J Eatough L D Hansen E A Lewis 《Journal of chromatographic science》1990,28(4):200-203
An ion chromatographic method is described for the determination of nicotine and cotinine in aqueous solutions. This method is based on a type of reversed-phase chromatography involving ion pair formation of protonated nicotine, cotinine, pyridine, and pyridine derivatives. Detection is accomplished by measuring the UV absorption at 262 nm. Detection limits for nicotine and cotinine are 8 ng/mL and 2 ng/mL, respectively. Analyses of environmental samples and spiked environmental samples by both this ion chromatographic method and a previously reported gas chromatographic method have been used to demonstrate the accuracy and precision of this technique. The results of the analyses of both sets of samples by the two methods are in excellent agreement with a linear correlation coefficient of 0.97. 相似文献
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Sousa J Alves G Abrantes J Fortuna A Falcão A 《Analytical and bioanalytical chemistry》2012,403(1):93-129
Fluoroquinolones are one of the most promising and intensively studied drugs of contemporary anti-infective chemotherapy.
New fluoroquinolone antibacterials with improved pharmacokinetic properties and a broad spectrum of activity have been developed,
opening new windows of opportunity for clinical use. To our knowledge, no comprehensive and critical review of the analytical
methods for the determination of these agents, which correspond to the third- and fourth-generation quinolones, has yet been
published. This work summarizes for the first time most of the liquid chromatographic methods reported in the literature for
the separation and quantification of the new fluoroquinolones in biological matrices and pharmaceutical formulations. A systematic
and detailed survey of physicochemical properties, sample preparation procedures, and chromatographic and detection conditions
is presented herein. In the course of this review several liquid chromatographic methods are discussed: reversed-phase high-performance
liquid chromatography (RP-HPLC), ion-exchange high-performance liquid chromatography (IEX-HPLC), hydrophilic interaction liquid
chromatography (HILIC), high-performance thin-layer chromatography (HPTLC) and other chiral chromatographic methods. Their
advantages, applicability and limitations are also examined. 相似文献
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维生素D是一种对于维持人体健康具有重要作用的脂溶性维生素,25-羟基维生素D是其在人体内循环和存储的主要形式。食品中维生素D和25-羟基维生素D前处理的通常采用碱皂化、有机溶剂提取、固相萃取或者半制备色谱净化;其测定方法多为放射免疫法和液相色谱法。液相色谱串联质谱凭借高灵敏度和高准确度,目前在食品中维生素D和25-羟基维生素D测定中发挥重要作用。近年来二维液相色谱和超高效超临界流体色谱由于其强大的分离能力,在食品中维生素D和25-羟基维生素D的分析中表现出强大的潜力。该文综述了近年来食品中维生素D和25-羟基维生素D的检测方法及二者在动物食品和植物食品中的含量分布研究,以期为建立适合不同食物样品的测定方法,指导居民合理膳食,进行膳食摄入量评估等研究工作提供参考。 相似文献
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《Analytical letters》2012,45(8):1217-1233
The measurement of the primary nicotine metabolites, cotinine and trans-3′-hydroxycotinine, is a useful biomarker of nicotine exposure and metabolism genetics for smoking cessation research. Herein is described an ultra-high performance liquid chromatography–tandem mass spectrometry method for the determination of these primary nicotine metabolites in urine. Urine samples were diluted one hundred-fold with water and introduced into an ultra-high performance liquid chromatography triple quadrupole mass spectrometer using positive ion electrospray ionization with multiple reaction monitoring. Levels of urinary nicotine metabolites: cotinine, trans-3′-hydroxycotinine, and their respective glucuronides were determined directly using deuterated internal standards and compared with indirect determination by enzymatic hydrolysis. The assay was applied to a community sample of smokers’ urine (n = 280). The assay demonstrated satisfactory performance (relative standard deviation of 1.6–6.5 percent at the 1000 nanograms per milliliter level and >98 percent recovery) suitable for application to smoking studies with a run time less than five minutes. The mean (min-max) levels of cotinine and cotinine-glucuronide were 968 (31-3831) and 976 (9-5607) nanograms per milliliter. The mean (min-max) levels of trans-3′-hydroxycotinine and trans-3′-hydroxycotinine-glucuronide were 3529 (13-21337) and 722 (0-4633) nanograms per milliliter. Direct determination of glucuronide metabolites was superior to indirect measurement using enzymatic hydrolysis, where there was evidence of loss of metabolites during sample preparation. A sensitive and selective ultra-high performance liquid chromatography–tandem mass spectrometry assay was successfully developed for the determination of cotinine, trans-3′-hydroxycotinine, and their glucuronides in urine. The rapid and simple sample preparation makes this assay suitable for high throughput studies involving nicotine metabolism phenotype for both cytochrome P450 2A6 and uridine 5′-diphospho-glucuronosyltransferase, smoking prevalence, and cessation studies. 相似文献