气相色谱-质谱法同时测定人体尿液中16种邻苯二甲酸酯

建立人尿中16种邻苯二甲酸酯的离子阱气相色谱-质谱方法。该方法采用正己烷萃取,经HP-5MS色谱柱(30 m×0.25 mm×0.25μm)分离,使用GC-MS选择离子扫描模式进行分析测试。结果表明:16种邻苯二甲酸酯在0.05～4 mg/L范围内线性良好,r20.99,方法检出限为0.001～0.017 mg/L,定量下限(LOQ)为0.002～0.056 mg/L,加标回收率在80%～120%之间;RSD(n=8)小于10%。并采用该方法测定了90份人尿中的16种邻苯二甲酸酯,检出10种邻苯二甲酸酯,其中DIBP检出率高达50%,DEHP检出率也达到22%。     

液-液小体积萃取GC-MS方法快速测定地表水中的硝基苯类、氯苯类及邻苯二甲酸酯类化合物

建立了一种以容量瓶为萃取容器的液-液小体积萃取GC-MS快速测定地表水中硝基苯类、氯苯类及邻苯二甲酸酯类化合物的分析方法。该方法具有操作简单快速、适用性广和试剂用量很少等特点。当萃取试剂用量为1mL时(约为一般常规液液萃取用量的数十分之一),萃取富集效率可达100倍,回收率为76%～120%,相对标准偏差为3%～8%,检出限为0.2～0.9μg/L。对实际地表水水样中的硝基苯、氯苯类及邻苯二甲酸酯化合物进行了定性定量分析,结果令人满意。     

简化高效液相色谱法检测邻苯二甲酸酯

为实现对水环境中邻苯二甲酸酯的准确快速检测,根据邻苯二甲酸酯的中等极性特点,采用100％甲醇为简化的高效液相色谱流动相,固相萃取-高效液相色谱法检测水环境中4种邻苯二甲酸酯(邻苯二甲酸二甲酯DMP、邻苯二甲酸二丁酯DBP、邻苯二甲酸二(2-乙基己基)酯DEHP、邻苯二甲酸二辛酯DOP).4种邻苯二甲酸酯的分离分析时间均小于8min,定量检测限依次为:0.010,0.025,0.035和0.040ng/mL,加标回收率为93.2％～98.5％.实验表明:该方法简单快速,灵敏度、精密度、重现性和回收率均较好,能很好地用于水环境中邻苯二甲酸酯的分析检测.     

超声萃取/ 快速溶剂萃取-气质联用测定烟用拉线中邻苯二甲酸酯类物质

建立了采用气相色谱-质谱联用法(GC-MS) 同时检测10 种邻苯二甲酸酯类物质的方法,并用此方法测出了5 种烟用拉线中含有的2 种邻苯二甲酸酯类物质DEHP 和DIBP 的含量。以正己烷为提取溶剂,分别采用超声提取法和ASE 快速溶剂萃取法对烟用拉线进行了萃取。结果表明,超声提取的回收率在78. 3% ~91. 7%之间,RSD 在7. 95% ~9. 82%之间,ASE 萃取技术的回收率在82. 2% ~93. 8%之间,RSD 在4. 95% ~7. 87%之间;ASE 萃取技术有较高的回收率和精密度,适宜用于烟用拉线检测前的处理过程。     

气相色谱-质谱/离子选择法对PE保鲜膜中邻苯二甲酸酯类的测定

增塑剂中的邻苯二甲酸酯类严重影响人类的生命健康。该文以正己烷为萃取剂,采用超声萃取法提取PE保鲜膜中的邻苯二甲酸酯;利用气相色谱-质谱法/选择离子监测模式(GC-MS/SIM),测定PE保鲜膜中的4种邻苯二甲酸酯(DBP、BBP、DEHP、DNOP)的含量;建立气相色谱-质谱/离子选择法测定PE保鲜膜中邻苯二甲酸酯含量的分析方法。实验结果表明该方法在0.1~0.8 mg/L范围内具有良好的线性关系,检测限在0.20~0.60 mg/kg之间,加标水平为0.3 mg/L时的平均回收率为80.2%~104.8%,测定结果的相对标准偏差为1.76%~5.52%。该方法操作简便、准确性好、快速、灵敏,适于PE保鲜膜中4种邻苯二甲酸酯类含量的测定。     

食品接触用塑料产品中19种邻苯二甲酸酯类增塑剂GC-MS检测研究

研究建立了食品接触用塑料产品中19种邻苯二甲酸酯类增塑剂的气相色谱-质谱联用仪(GC-MS)法快速检测方法。塑料产品以正己烷为萃取溶剂,采用超声萃取法对产品中邻苯二甲酸酯类增塑剂进行萃取,萃取液浓缩过滤后进行测定。19种邻苯二甲酸酯类增塑剂在0.05~1mg/L、0.5~10mg/L范围内线性良好,方法检出限(MDL)为0.1238mg/kg~0.9714mg/kg,加标回收率为89.6%~112.9%,相对标准偏差(RSDs)为2.61%~6.36%。该方法重现性好,检出限低,检测结果准确,可用于食品接触用塑料产品中19种邻苯二甲酸酯类增塑剂含量的检测,为食品接触材料中邻苯二甲酸酯质量控制提供相应的技术支撑。     

微波辅助萃取-气质联用/选择离子监测法同时测定涂布纸中多种邻苯二甲酸酯类增塑剂

以丙酮为萃取溶剂,采用微波辅助萃取技术萃取涂布纸中的邻苯二甲酸酯类增塑剂,萃取产物进行气相色谱/质谱-选择离子监测法测定,从而建立了一种同时测定涂布纸中多种邻苯二甲酸酯类增塑剂的方法。该方法简便快捷、灵敏度高、定性定量准确。方法的精密度试验RSD为3.12-5.97%,加标平均回收率为82.35-103.68%。在S/N=3的条件下,DINP和DIDP的检出限分别为1.0、2.0mg/kg,其余各组分检出限均小于0.4mg/kg。本方法可用于涂布纸中多种邻苯二甲酸酯类增塑剂的同时测定。     

含油脂食品中邻苯二甲酸酯的前处理及其GC-MS测定方法

建立了15种邻苯二甲酸酯的提取-固相萃取净化-气相色谱/质谱检测分析方法。讨论了含油脂食品中邻苯二甲酸酯的提取、净化方法,优化了色谱分离条件。研究表明,该前处理方法具有较高的净化效率,且缩短了整个检验所需时间;15种邻苯二甲酸酯的方法线性范围为50～2000μg/L,相关系数均大于0.999,加标样品在200μg/L和2000μg/L两个浓度水平下,相对标准偏差在1.1%～11.2%范围,除邻苯二甲酸二甲酯较低外,样品加标回收率均在70%～120%之间。检测限在0.07～1.2μg/L范围(S/N=3)。     

气相色谱法测定聚氯乙烯固体药用硬片中17种邻苯二甲酸酯增塑剂

建立了气相色谱法测定聚氯乙烯固体药用硬片中17种邻苯二甲酸酯增塑剂。17种邻苯二甲酸酯成分在各自线性范围内相关系数r0.996,方法的检出限为0.38~4.86μg/g(S/N=3),样品加标回收率在91.0%~112.4%之间,加标样品的RSD为4.83%~5.59%。应用本方法对11份样品进行了分析,并用气相色谱-质谱联用法进行了对比测定,结果表明,本方法经济、简单、准确、高效,适用于聚氯乙烯固体药用硬片中邻苯二甲酸酯增塑剂的测定。     

分散液液微萃取--气相色谱法测定海水中的邻苯二甲酸酯

本文以分散液液微萃取作为样品的前处理技术,建立了气相色谱-氢火焰离子化检测器分析海水中邻苯二甲酸酯的新方法。优化了分散液液微萃取的萃取条件,6种邻苯二甲酸酯线性范围在1.0-50.0μg/mL之间,R≥0.9953,回收率在92.5%~106.4%之间,最低检测限为0.15μg/mL。将方法应用于海水中邻苯二甲酸酯类的检测,易于操作,分析结果可靠。     

离子色谱法测定饮用水中的磷酸盐

建立了单柱阴离子色谱测定饮用水中磷酸盐的方法,并对实际水样进行了测定。磷酸盐浓度在0.1-4.0mg/L范围内与峰面积线性回归相关系数0.9992,检出限为0.02mg/L,保留时间和峰面积相对标准偏差分别为0.09%和0.52%,回收率为96.2-102.4%。     

GC-MS法同时测定橡皮擦中22种邻苯二甲酸酯增塑剂

建立了气相色谱-质谱(GC-MS)分段选择离子监测(SIM)模式分析同时测定橡皮擦中22种邻苯二甲酸酯(PAEs)增塑剂含量的方法。该方法具有良好线性,相关系数R均大于0.999,检测限在1.3 mg/kg～128.9 mg/kg之间,平均回收率在70.2%～105.6%,相对标准偏差在2.57%～9.88%之间。通过该方法对国内橡皮擦中PAEs增塑剂进行检测,实际样品均检出邻苯二甲酸二(2-乙基)己酯(DEHP),含量最高达32.5%。     

Static subcritical water extraction combined with anion exchange disk sorption for determining chlorinated acid herbicides in soil

Static subcritical water extraction (SbWE) was coupled with collection on a strong anion exchange (SAX) disk for the determination of chlorinated acid herbicides and their esters in soil. With 100-150 degrees C water, esters were hydrolyzed into their acid form, and the herbicide acids extracted by subcritical water were trapped onto/into a SAX disk as the extraction cell was cooled. The trapped solutes were then derivatized for gas chromatographic (GC) analysis by placing the disk into a GC autosampler vial containing 1 mL of N,O-bis(trimethylsilyl)trifluoroacetamide derivatizing reagent. With the static SbWE/SAX disk extraction, nearly quantitative recoveries (typically over 80%) were obtained at 100 degrees C for 30 min in the extraction of herbicide acids and esters spiked on several different soils covering a range of organic content from 0.3 to 12%. Good agreements were reached between this method and EPA method 8151 for aged spiked soils. Detection limits of the static SbWE/SAX disk extraction were from 0.05 to 0.5 ppm and from 0.01 to 0.5 ppm using GC/electron capture detector and GC/mass spectrometry, respectively. The method is fast and simple and uses a small amount of organic solvent.     

红外光谱法测定柴油中脂肪酸甲酯的检出限及不确定度评定

柴油中脂肪酸甲酯含量的测定广泛采用红外光谱法,针对此方法的检测能力和准确性进行了研究.试验测定红外光谱法检测柴油中脂肪酸甲酯的检出限和定量限分别为0.0066 g/L和0.0220 g/L,加标回收率为99.2％～101.3％,结果表明试验方法具备良好的准确性,能够准确灵敏地检测柴油中脂肪酸甲酯.测定的合成相对标准不确...     

Anti-inflammatory prodrugs as plasticizers for biodegradable implant materials based on poly(3-hydroxybutyrate)

Salicylic and acetylsalicylic acid esters were tested as plasticizers for biodegradable poly(3-hydroxybutyrate) (PHB). The aim is the combination of plasticizing and anti-inflammatory properties in the fabrication of implant materials. Solution-cast films made of mixtures of PHB and 30% ester showed plasticization accompanied by a decrease of elastic modulus and an increase in elongation at break in comparison with pure PHB films. However, the number of usable plasticizers from the group of the salicylic acid and acetylsalicylic acid esters is limited. Short-chain derivatives are volatile while long-chain compounds tend to crystallize. In both cases PHB films embrittle within short time. Moreover, some derivatives show a fast release in an aqueous environment. As alternative nonsteroidal anti-inflammatory prodrugs arylpropionic acid esters were tested as plasticizers. The addition of ketoprofen ethyl ester led to PHB films with decreased brittleness. In summary, various esters of anti-inflammatory drugs show plasticizing effects on solution-cast PHB films comparable with those of commonly used citric acid esters.     

LC-MS/MS assay for protein amino acids and metabolically related compounds for large-scale screening of metabolic phenotypes

A modified LC-MS/MS method for large-scale screening of metabolic phenotypes was developed and validated. Twenty amino acids and 5 metabolically related compounds are measured within 4 min using multiple reaction monitoring (MRM) transitions selective for each compound. Separation with a short C18 column and rapid gradient using the ion-pairing reagent perfluoroheptanoic acid allows chromatographic resolution of the isomers Ile and Leu and improved chromatographic peak shapes for Lys, Arg, and His. MRM transitions were established with capability to distinguish isomers Leu from Ile and Thr from homoserine even when chromatographic resolution is incomplete. The reproducibility of the assay was tested by adding eight stable isotope-labeled amino acid standards (AA*) to extracts of Arabidopsis thaliana seeds. In intra- and interday assay comparisons, mean coefficients of variation of the peak area ratios of AA/AA* were less than 5% for all but Gly/Gly-D2-15N1. Recoveries of these eight amino acids ranged from 62 to 94% and suppression of signal by the matrix were 31-65%. Dilution of seed extracts reduced ion suppression for early-eluting amino acids but had minimal effects for those eluting later. The intra- and interday accuracies for these eight amino acids were 77-131 and 88-133% of nominal concentrations, respectively.     

Arsenic speciation in rice and soil containing related compounds of chemical warfare agents

Diphenylarsinic acid, phenylarsonic acid, methylphenylarsinic acid (MPAA), dimethylphenylarsine oxide (DMPAO), and methyldiphenylarsine oxide (MDPAO) in soil and rice were extracted, separated by reversed-phase chromatography, and quantified by ICPMS with a membrane desolvating system. For the extraction of arsenicals from rice grain and straw, 68% HNO3 provided better extraction efficiency than water, 50% methanol, or 2.0 mol L(-1) trifluoroacetic acid. For the extraction from soil, 68% HNO3 provided better extraction efficiency than H2O, 1 mol L(-1) H3PO4, or 1 mol L(-1) NaOH. The contaminated soil contained all five aromatic arsenicals along with inorganic arsenicals as main species (5.86 +/- 0.19 microg of As kg(-1): 60.8 +/- 2.0% of total extracted As). After pot experiments, rice straw contained mainly DMPAO (7.71 +/- 0.48 microg of As kg(-1): 60.5 +/- 3.7%), MDPAO (0.91 +/- 0.07 microg of As kg(-1): 7.2 +/- 0.5%), and inorganic As (2.85 +/- 0.20 microg of As kg(-1): 22.3 +/- 1.6%). On the other hand, rice grain contained mainly MPAA (1.17 +/- 0.04 microg of As kg(-1): 86.7 +/- 2.7%). The root uptake of each species from the soil and transport from straw to grains were significantly related to the calculated log K(ow) values.     

Activities of clays and ion exchange resins in the synthesis of phthalate esters

Phthalate esters are used as plasticisers, solvents and perfumery compounds. Usually homogenous polluting and corrosive acids are used as catalysts for esterification which leave traces of inorganic impurities in the final product and they also impart coloration. This paper evaluates the activities of acid treated clays and ion exchange resins in the esterification of phthalic anhydride using methanol as the model alcohol.

Determination of the Acidic Degradation Products, Acetic, Propionic, Butyric, and Phthalic Acid in Aqueous Pseudolatexes of Cellulosic Esters by High Performance Liquid Chromatography

An isocratic, reversed-phase HPLC method was developed to quantify the organic acids, acetic, propionic, butyric, and phthalic acid, formed as a result of ester hydrolysis, in pseudolatexes of cellulosic esters. Colloidal dispersions of cellulose acetate, cellulose acetate butyrate, and cellulose acetate propionate were prepared by a microfluidization-solvent evaporation method. Dispersions of cellulose acetate phthalate were prepared by redispersion of a spraydried commercial pseudolatex. The acids were detected at 210 nm, the mobile phase being 0.025 M phosphate buffer: methanol (80:20 v/v%, pH 3.0). The peak height response was linear over the studied concentration range of 2 - 10 mM/L for the aliphatic acids and 20-100 μM/L for phthalic acid. The minimum detectable quantities for acetic, propionic, butyric, and phthalic acid were 0.02 mM/L, 0.05 mM/L, 0.1 mM/L, and 0.0005 mM/L, corresponding to a % change in acetyl, propionyl, butyryl, and phthalyl content of 4.0 × 10⁴, 1.2 × 10³, 2.9 × 10³, and 2.8 × 10^-5 for a 30% w/v pseudolatex. The colloidal polymer particles were separated by ultracentrifugation, filtration, or flocculation with aluminum chloride solution before analysis of the aqueous phase. Similar acid concentrations were obtained for the three separation methods. The recovery from spiked samples was almost complete for acetic, approximately 90% for propionic acid, and less than 80% for butyric acid.