毛细管电泳法同时分析水、乳、膏类化妆品中5种有机酸

建立了毛细管电泳同时分析5种有机酸的间接紫外检测法。优化了背景电解质溶液中表面活性剂十四烷基三甲基溴化铵（TTAB）的浓度和溶液pH。优化后的电泳分析条件如下：含0.4 mmol/L TTAB的15 mmol/L邻苯二甲酸氢钾溶液为背景电解质（pH 5.6）；分离电压-15 kV；检测波长254 nm；分离温度25℃；进样压力5 kPa；进样时间5 s。在此条件下，可在6 min内完成5种有机酸的同时分离检测，线性范围为甲酸15~600 mg/L、苹果酸30~800 mg/L、柠檬酸20~700 mg/L、乙醇酸40~500 mg/L和乳酸30~5000 mg/L，线性相关系数为0.9983~0.9998；检出限为0.1~2.0 μg/g。该方法可用于检测水状、乳状、膏状3类化妆品中的5种有机酸。在3个加标水平下，有机酸分析的回收率为95.0%~101.6%，RSD在2.0%以内。该方法操作简单，分析快速，安全环保，灵敏度高，重现性好，有望用于化妆品生产和保存过程中有机酸的监测。     

逐级提取-高效液相色谱法快速测定植物组织中8种有机酸

针对植物组织中草酸存在的不同形态,建立了水和稀盐酸作为提取介质的逐级提取方法,获得了水溶态和酸溶态草酸及乙醇酸、乙醛酸、酒石酸、苹果酸、乙酸、柠檬酸、琥珀酸等有机酸。采用Hypersil ODS (200 mm×4.6 mm, 5 μm)色谱柱,以5 mmol/L磷酸二氢钾水溶液(pH 2.8)作为流动相,在进样量5 μL、检测波长210 nm、柱温30 ℃的条件下,通过分时段控制流速实现了8种有机酸的快速分离,同时去除了盐酸对酸溶态草酸测定的干扰。本方法精确灵敏、回收率高、重复性好,可应用于实际样品的测定分析。     

胶束电动毛细管色谱-间接紫外检测法测定糖蜜酒精废液中的有机酸

建立了一种利用胶束电动毛细管色谱-间接紫外检测法同时测定丙二酸、甲酸、酒石酸、苹果酸、琥珀酸、戊二酸、乙酸、乳酸和谷氨酸的新方法。以7.5 mmol/L邻苯二甲酸氢钾-1.5 mmol/L十六烷基三甲基溴化铵(用0.1 mol/L氢氧化钠调pH至6.50)混合液作为电泳介质,检测波长为300 nm,参比波长为210 nm,未涂层弹性石英毛细管(50 μm i.d.×64 cm)为分离通道,在6 min内实现了9种酸的完全分离。9种有机酸的浓度与其峰面积在一定的范围呈良好的线性关系,检出限均低于1.5 mg/L,迁移时间和峰面积的日内、日间相对标准偏差均小于6%。该法用于糖蜜酒精废液中有机酸的测定,结果令人满意,9种有机酸的样品加标回收率均在93%以上。     

固相萃取-高效液相色谱法测定蜂蜜中的有机酸

建立了固相萃取-高效液相色谱(SPE-HPLC)同时测定蜂蜜中5种有机酸(L-苹果酸、马来酸、琥珀酸、柠檬酸、D-苹果酸)含量的方法。蜂蜜经制样后过Bond Elutes SAX固相萃取(SPE)小柱净化,用C18-MS-II反相色谱柱(250 mm×4.6 mm, 5 μm)进行分离,流动相为2%偏磷酸溶液,流速为0.7 mL/min,检测波长为210 nm。在此条件下5种有机酸在相应的线性范围内其线性相关系数均大于0.9967;方法的回收率为86.0%～103.9%,相对标准偏差为5.7%～9.8%(n=6),检出限为0.06～9.4 mg/kg。所建立的方法可用于蜂蜜样品中有机酸的测定。     

在线富集离子色谱-质谱联用法同时测定饲料添加剂中的16种有机酸

建立了在线富集方式结合离子色谱-质谱(IC-MS)快速分离分析16种有机酸的方法。离子色谱配备自制富集柱和分离柱对有机酸进行在线富集和分离;质谱采用大气压化学电离源负离子电离方式(APCI^-),在选择离子监控(SIM)模式下对有机酸进行定性和定量分析。采用200 μL大体积进样,在线富集时间为3 min,以NaOH溶液作为淋洗液,梯度洗脱。结果表明,富集柱和分离柱对有机酸有很好的富集分离能力;16种有机酸在30 min内完全洗脱,并在一定浓度范围内线性关系良好;方法检出限(LODs)为0.01~0.22 mg/L;加标回收率为70.6%~110.8%,相对标准偏差(RSD)≤6.3%。该方法样品前处理简单,分离速度快,有机酸检测灵敏度高,适用于多种饲料添加剂样品中有机酸添加剂的检测。     

Flow injection on-line dialysis coupled to high performance liquid chromatography for the determination of some organic acids in wine

A combined system of flow injection on-line dialysis sample pretreatment and high performance liquid chromatographic separation/detection (FID-HPLC) was developed for simultaneous determination of six organic acids (tartaric, malic, lactic, acetic, citric and succinic acids). A sample or mixed standard solution (400 μL) was injected into a donor stream (water) of FID system and was pushed further through a dialysis cell, while an acceptor solution (water) was held in the opposite side of the dialysis membrane. The dialysate containing organic acids in the acceptor solution was then flowed to an injection loop of the HPLC valve, where it was further injected into the HPLC system and analysed under normal HPLC conditions, using a reversed-phase (C₁₈) analytical column and UV detection (210 nm). The order of elution was tartaric, malic, lactic, acetic, citric and succinic acids with the analysis time of 8 min. The FID system could be operated in parallel with HPLC separation, providing sample throughput of 7.5 h⁻¹. Dialysis efficiencies of six organic acids were in range of 4.6-9.5%. Calibration graphs for all the mentioned organic acids were linear over the range of 250-7500 mg L⁻¹. Precisions for all the organic acids were within 5.4%. The proposed system was successfully applied for analysis of some Thai wines. By spiking wine samples with mixed acid standard solutions, the percentage recoveries in range of 84-104 were found. This system has advantages of fast and high degrees of automation for dialysis sample pretreatment, on-line sample separation and dilution, good clean-up for prolongation of life-time of the HPLC column and low consumption of chemicals and materials.     

离子色谱-串联质谱法检测酒类产品中10种有机酸

建立了一种离子色谱-串联质谱(IC-MS/MS)测定白酒、黄酒、干红葡萄酒3种酒类样品中10种有机酸含量的方法。白酒样品氮吹后,经去离子水稀释,用IC-MS/MS分析检测;干红葡萄酒样品和黄酒样品,对比不同固相萃取小柱净化能力,最终选择石墨化炭黑固相萃取小柱进行净化,经去离子水稀释,用IC-MS/MS分析检测。选用高容量、强亲水性的Dionex IonPac^TM AS11-HC型阴离子分析柱进行分离,以淋洗液自动发生器在线产生的KOH水溶液为淋洗液,进行梯度淋洗。淋洗液经抑制器抑制后直接进入电喷雾电离串联质谱(ESI-MS/MS),采用负离子模式电离,多反应监测(MRM)模式检测,外标法定量。在该实验条件下:草酸、富马酸、马来酸、苹果酸、酒石酸、柠檬酸、奎尼酸和乌头酸在0.05~2 mg/L范围内线性关系良好;琥珀酸在0.05~5 mg/L范围内线性关系良好;乳酸在0.05~10 mg/L范围内线性关系良好(相关系数r²>0.99)。10种有机酸的检出限(S/N=3)在1.0~8.0 μg/L范围内,定量限(S/N=10)在3.5~26.5 μg/L范围内,在3个不同浓度的添加水平下,平均回收率在83.0%~112.1%之间,相对标准偏差≤9.1%,满足检测要求。该方法前处理简单,不使用有机溶剂,不需进行衍生化处理,测定快速、准确,灵敏度高,适用于3种酒类样品中10种有机酸的定量分析,为酒类食品的风味及品质测定提供方法支持。     

电堆集富集非水毛细管电泳同时测定水杨酸、肉桂酸、阿魏酸和香草酸

建立了同时分离测定水杨酸、肉桂酸、阿魏酸和香草酸的电堆集富集-非水毛细管电泳(NACE)的新方法。运行缓冲溶液为40mmol/L乙酸钠-2.5mmol/L氢氧化钠甲醇溶液,电压-25kV,在225nm波长下紫外检测。对电压、乙酸钠浓度、氢氧化钠浓度、进样时间、样品溶液等因素对电堆集及分离的影响做了系统的研究。水杨酸、肉桂酸、阿魏酸和香草酸分别在1.4~28mg/L、0.40~8.0mg/L、0.7~18mg/L和0.7~30mg/L范围内线性关系良好(r=0.9999、r=0.9997、r=0.9994、r=0.9997);回收率分别为95.8~99.6%、96.2~98·2%、95.7~105%和98.9~103%,基于3倍信噪比(S/N=3),4种有机酸的检出限分别为0.069、0.051、0.107和0.089mg/L。     

高效液相色谱法测定菌群降解纤维素产物中的糖、有机酸和醇

采用硫酸除钙和调节pH的样品预处理方法,利用高效液相色谱对菌群降解纤维素发酵液中的糖、有机酸和醇3类物质进行分析,待测组分与培养基成分能够得到有效分离。从菌群降解纤维素发酵液中检出纤维二糖、葡萄糖、乙醇、丁醇、甘油、乙酸与丁酸并进行了定量分析,7种组分的检出限范围为0.10~2.00 mg/L,线性相关系数均大于0.9996,线性范围为0.020~1.000 g/L,回收率为85.41%~115.60%,相对标准偏差(RSD)为0.22%~4.62%(n=6)。该方法准确可靠,可实现对菌群降解纤维素发酵液中糖、醇和有机酸的同时准确测定。     

离子色谱法测定水中4种有机酸

建立了水样中甲酸、乙酸、丙烯酸和甲基丙烯酸的离子色谱测定方法,采用IonPac AS11-HC阴离子分离柱,以KOH为淋洗液,采用浓度梯度洗脱,可同时测定上述4种有机酸。方法对实际水样中甲酸、乙酸、丙烯酸和甲基丙烯酸的平均加标回收率在80.2%~103.3%,相对标准偏差在5.8%之内,检出限分别为:0.005,0.003,0.005和0.004mg/L;定量下限分别为:0.020,0.012,0.020和0.016mg/L。方法准确、简便、环保,能够满足实际水样的测定需要,且水样中常见的阴离子不会对目标污染物的测定产生影响。     

On-line solid phase extraction of humic acid from environmental water and monitoring with flow-through chemiluminescence

An on-line solid phase extraction device combined with flow-through chemiluminescence monitoring was presented for the enrichment and determination of humic acid (HA) in water samples. The chemiluminescence principle was based on the enhancement effect of HA on the Ce(IV)/H(2)SO(4)-rhodamine 6G chemiluminescence system. For sample pretreatment, the on-line solid-phase extraction (SPE) material was packed into a cartridge which was then installed in the manifold. Experimental parameters including reagent concentration, flow rate and extraction time, were optimized. Under the optimized conditions, the relative standard deviation was 3.6% for determining 2 mg L(-1) HA standard solution and the detection limit was 3 μg L(-1). The proposed method was successfully applied to the determination of HA in the range of 0.1-35 mg L(-1). The results were validated by spike recovery experiments. The recovery was from 74.0% to 121%, which was good enough for the determination of HA in environmental waters.     

两性化合物与离子对试剂的混合物作流动相的流动相离子色谱法测定气溶胶中水溶性阴离子

用流动相离子色谱法(MPIC),以两性化合物与离子对试剂的混合溶液为流动相,在C18柱上抑制电导检测分析气溶胶中常规无机阴离子和有机酸。实验采用氢氧化四丁基铵(TBAOH)为离子对试剂,与两性化合物3-(N-吗啉)-1-丙磺酸(MOPS)混合,加入Na2CO3无机添加剂作流动相,其浓度为1mmol／L TBAOH／5mmol／LMOPS／0．5mmol／LNa2CO3。分离柱采用硅质C18柱,抑制电导检测。可以较好地分离和检测常见的无机和有机阴离子。该方法具有较好的重现性和线性关系,F^-、Cl^-、NO2^-、Br^-、C3H3O3^-、NO3^-的回收率分别为102．0％、104．6％、102．4％、97．8％、97．75％和102．5％;检出限分别为0．017、0．014、0．0048、0．036、0．16和0．017mg／L。     

离子色谱法同时分析董酒中的有机酸与无机阴离子

研究了用离子色谱法同时分析董酒中可离解性有机酸和无机阴离子。首次采用邻苯二甲酸氢钾和邻苯二甲酸的混合水溶液作淋洗剂,改善了分离效果,提高了检测灵敏度。所建立的方法无需进行样品前处理,无干扰,有一定的实用价值。     

离子排斥色谱法测定生脉注射液中的有机酸

1引言生脉注射液是由红参、麦冬和五味子3种药材经提取后制成的灭菌水溶液,为国家中药保护品种,具有益气养阴,复脉固脱的功效。前期的分析实验表明,生脉注射液中含有有机酸类成分。根据生脉注射液的生产工艺和3种药材的的化学成分研究报道,分析生脉注射液中的有机酸主要来源于五味子。五味子含有柠檬酸、苹果酸、琥珀酸等多种有机酸成分。目前,有机酸的分析方法有气相色谱法[1]、高效液相色谱法[2]、毛细管电泳法[3]及离子色谱法[4]。这些方法专属[5]     

Simultaneous analysis of small organic acids and humic acids using high performance size exclusion chromatography

An accurate and fast method for simultaneous determination of small organic acids and much larger humic acids was developed using high performance size exclusion chromatography. Two small organic acids, i.e. salicylic acid and 2,3‐dihydroxybenzoic acid, and one purified humic acid material were used in this study. Under the experimental conditions, the UV peaks of salicylic acid and 2,3‐dihydroxybenzoic acid were well separated from the peaks of humic acid in the chromatogram. Concentrations of the two small organic acids could be accurately determined from their peak areas. The concentration of humic acid in the mixture could then be derived from mass balance calculations. The measured results agreed well with the nominal concentrations. The detection limits are 0.05 mg/L and 0.01 mg/L for salicylic acid and 2,3‐dihydroxybenzoic acid, respectively. Applicability of the method to natural samples was tested using groundwater, glacier, and river water samples (both original and spiked with salicylic acid and 2,3‐dihydroxybenzoic acid) with a total organic carbon concentration ranging from 2.1 to 179.5 mg C/L. The results obtained are promising, especially for groundwater samples and river water samples with a total organic carbon concentration below 9 mg C/L.     

阀切换-离子色谱法测定1,2-环氧丁烷产品中有机酸

建立了阀切换-离子色谱法测定1,2-环氧丁烷（1,2-BO）产品中有机酸（甲酸、乙酸和丙酸）的方法。样品经乙醇稀释后,通过阀切换技术,有机酸被IonPac TAC-ULP1捕集柱捕集,然后进入IonPac AS11分析柱分离,并由电导检测器检测。结果表明：甲酸、乙酸和丙酸均能实现较好地分离,在各自的范围内其色谱峰面积呈现良好的线性关系。实际样品的加标回收率为92.5%~111.8%,相对标准偏差小于5.6%（n=3）,检出限为0.60~4.80 μg/L。该方法具有前处理简单、快速、准确等特点,适用于不溶于水的有机体系中有机酸的分析。     

离子色谱-柱切换法测定土壤浸出液中的氟离子

建立了离子色谱-柱切换测定土壤浸出液中氟离子的方法。使用柱切换技术,将样品通过高聚物反相色谱柱进行在线预处理,分离氟离子和小分子有机酸,同时除去水溶性有机杂质,采用收集环收集氟离子并进入分析系统分析,消除了测定氟离子时普遍存在的干扰问题。分析系统的淋洗液为KOH溶液,流速为1.0 mL/min,采用抑制性电导检测,外标法定量。氟离子的线性范围为0.05~10.0 mg/L,相关系数为0.9999,加标回收率为103.4%~105.3%,相对标准偏差为2.0%~2.1%,检出限 (S/N=3)为5.50 μg/L。该方法适用于测定复杂基体样品中的氟离子。     

Determination of phenols in landfill leachate-contaminated groundwaters by solid-phase extraction

A solid-phase extraction method for phenols in landfill leachates was developed and optimized in order to solve the expected and observed problems associated with an anaerobic matrix containing high concentrations of salts and organic matter. Isolute ENV+ cartridges exhibited the best retention of phenols of the four sorbents examined, and was the only cartridge which a 1 L leachate sample could pass through. With the other cartridges, clogging made this impossible. The final method, which included 27 different phenols, gave detection limits of <0.1 microg/L (drinking water concentration limit for pesticides) for most phenols (25), and for 12 phenols <0.01 microg/L. Recovery rates (determined for four concentrations in the range 1-25 microg/L, two replicates of each) were in the range 79-104% (SD 1-12%), except for phenol (26+/-1.3%) and 2-methoxyphenol (62+/-4.2%). Up to 12 different phenols could be identified in leachates from three Danish landfills, ranging in concentration from 0.01 to 29 microg/L, which is at the lower end of the concentration range usually found for phenols in landfill leachates (sub-microg/L to mg/L).     

淋洗液自动发生-离子色谱法同时测定食品中的21种有机酸

建立了一种利用离子色谱法同时测定样品中奎尼酸、乙酸、丙酮酸、草酰乙酸、甘露酸、乳酸、琥珀酸、苹果酸、酒石酸、草酸、富马酸、抗坏血酸、α-酮戊二酸、肉桂酸、水杨酸、柠檬酸、异柠檬酸、阿魏酸、顺乌头酸、反乌头酸、β-香豆酸等21种有机酸的方法。样品经提取、脱色、过滤后用IonPac AS11分离柱分离,以EG40自动淋洗液发生器生成的5~34 mmol/L KOH为淋洗液洗脱,抑制电导检测器检测。21种有机酸的浓度与其峰面积在一定的范围内呈良好的线性关系,检出限均低于0.188 mg/L,加标回收率为91.5%~101.8%。该法用于多种食物样品中有机酸的测定,结果令人满意。     

高效液相色谱法测定铬超富集植物李氏禾根系分泌物中的有机酸

建立了高效液相色谱（HPLC）测定Cr超富集植物李氏禾根系分泌物中低相对分子质量有机酸的分析方法。采用XSelect HSS T3色谱柱（250 mm×4.6 mm,5 μm,Waters）,以40 mmol/L磷酸二氢钾-磷酸缓冲溶液（pH=2.40）作流动相,流速1.0 mL/min,柱温25℃,在波长205 nm处检测。该方法在13 min内简便快速地分离出8种有机酸（草酸、酒石酸、苹果酸、乳酸、甲酸、乙酸、马来酸和柠檬酸）,且峰形良好。有机酸的检出限（LOD）为0.12~12.32 mg/L;草酸的加标回收率为73.15%,其他有机酸的加标回收率为94.54%~109.98%。李氏禾的根系分泌物中各有机酸含量分别为酒石酸（130.90±1.44）μg/g（根干重）、苹果酸（1031.34±4.38）μg/g（根干重）、乳酸（65.54±1.01）μg/g（根干重）、马来酸（0.96000±0.00367）μg/g（根干重）和柠檬酸（201.50±1.13）μg/g（根干重）。该方法简便快速,灵敏可靠,适用于植物根系分泌物样品中有机酸的测定。