咪唑离子液体用于反相色谱流动相添加剂分析苯甲酸和山梨酸

开展了咪唑离子液体用于反相色谱流动相进行苯甲酸和山梨酸分析的研究。考察了咪唑离子液体种类与浓度、甲醇浓度、紫外检测波长等因素对分离、检测苯甲酸和山梨酸的影响,并探讨了2种分析物的保留规律。建立了以咪唑离子液体为流动相添加剂的反相色谱测定苯甲酸和山梨酸的分析方法。采用Agilent ZORBAX ODS反相色谱柱,以甲醇-0.2 mmol/L氯化1-丁基3-甲基咪唑水溶液(40∶60,体积比)为流动相,紫外检测波长230 nm,流速1.0 mL/min,色谱柱温度35℃时,可在7.0 min内实现苯甲酸和山梨酸的分离和检测。苯甲酸和山梨酸的线性范围为1.0～100.0 mg/L,相关系数(r)高于0.999 5,检出限均为0.02 mg/L。将方法应用于饮料样品中苯甲酸和山梨酸的测定,加标回收率为93.9%～104%,相对标准偏差(RSD)不大于4.0%,满足定量分析的要求。     

离子液体作高效液相色谱流动相添加剂测定水杨酸

建立了以离子液体作反相高效液相色谱流动相添加剂测定水杨酸的方法.实验以ZORBAX ODS反相色谱柱为分离柱,采用紫外检测方法,研究了检测波长、离子液体烷基链长度、离子液体溶液的浓度以及pH值等对分离和测定的影响.优化的色谱条件为:以体积比60:40的甲醇-3.0 mmol/L1-丁基-3-甲基咪唑四氟硼酸盐溶液(乙酸...     

离子液体作高效液相色谱流动相添加剂分离测定芳香族羧酸

以离子液体作反相高效液相色谱流动相添加剂,建立了分离测定对氨基苯甲酸、邻苯二甲酸、对羟基苯甲酸、水杨酸、苯甲酸、邻甲苯甲酸6种芳香族羧酸的方法。以C18反相色谱柱为分离柱,采用紫外检测方法,以离子液体作高效液相色谱流动相添加剂,考察了检测波长、甲醇含量、离子液体溶液的pH值、离子液体烷基链长度以及离子液体溶液浓度等分离及测定条件。优化得到的色谱条件为:以甲醇和1.0mmol/L 1-丁基-3-甲基咪唑四氟硼酸盐水溶液(pH 3.0)(体积比40∶60)为流动相;检测波长240 nm;流速1.0 mL/min;柱温30℃。在优化条件下对6种芳香族羧酸进行梯度洗脱,约在16.5 min内分离完全;在5~120 mg/L范围内,线性系数均在0.999以上;检出限为0.026~0.082 mg/L。方法的平均加标回收率为98.3%~103.8%,相对标准偏差不高于0.63%。将该方法应用于药品复方紫荆皮水杨酸溶液和足君清酊剂中芳香族羧酸的测定,结果满意。     

以离子液体为流动相的高效液相色谱-间接紫外检测法分析四甲基按根离子

建立了四甲基铵根离子的反相高效液相色谱-间接紫外检测分析法.以ZORBAX ODS反相色谱柱为分离柱,采用间接紫外检测方法,考察了紫外检测波长和离子液体+有机溶剂(乙腈、甲醇)流动相对分离和测定四甲基铵根离子的影响.最佳色谱条件为:以80% 1-乙基-3-甲基咪唑四氟硼酸盐水溶液(0.5 mmol/L,乙酸调pH 3....     

以咪唑离子液体为紫外吸收试剂的高效液相色谱/间接紫外检测法分离测定烷基磺酸盐

建立了以咪唑离子液体为背景紫外吸收试剂间接检测无紫外光吸收的烷基磺酸盐的高效液相色谱法。该方法采用反相C18色谱柱,以咪唑离子液体-有机溶剂为流动相,实现了2种烷基磺酸盐的分离和检测。研究了检测波长、有机溶剂和咪唑离子液体种类、浓度、pH值等因素对分离和测定的影响,探讨了保留规律,优化了色谱条件。结果表明,在柱温30℃,流速1.0 mL/min,检测波长210 nm,以0.7 mmol/L 1-乙基-3-甲基咪唑四氟硼酸盐水溶液(2 mmol/L磷酸二氢钠-磷酸调至pH 3.0)-甲醇(55∶45)作为流动相,戊烷磺酸钠和庚烷磺酸钠可在10 min内完全分离,线性范围分别为0.8~200 mg/L和2.5~200 mg/L,线性系数均达到0.999以上,检出限分别为0.24,0.75 mg/L。将方法应用于环境水样的测定,加标回收率为98.3%~99.1%,相对标准偏差小于1.5%。该方法准确、可靠,可以满足定量分析的要求。     

咪唑离子液体作为流动相添加剂的整体柱离子对色谱快速分析哌啶阳离子

以咪唑离子液体作为流动相添加剂,建立了哌啶离子液体阳离子的整体柱离子对色谱-间接紫外检测分析方法。系统研究了流动相、流速等因素对哌啶阳离子分离测定的影响情况。流动相中的咪唑离子液体不仅起到了背景紫外吸收剂的作用,还改善了阳离子的分离效果。用0.5mmol/L 1-乙基-3-甲基咪唑四氟硼酸盐-0.1mmol/L庚烷磺酸盐水溶液(pH=4.5)/甲醇(90/10,V/V)作为流动相,流速3.0mL/min,检测波长210nm,N-甲基-N-乙基、N-甲基-N-丙基和N-甲基-N-丁基哌啶阳离子在3.0min之内实现基线分离。3种哌啶阳离子的检出限分别为0.13、0.34和0.42mg/L。该方法测定实验室合成的哌啶离子液体样品的加标回收率范围为94%~98%。     

整体柱离子对色谱-间接紫外检测法快速分析吡咯烷离子液体阳离子

建立了快速分析无紫外光吸收的吡咯烷离子液体阳离子的离子对色谱-间接紫外检测法。采用反相硅胶整体柱,以(背景紫外吸收试剂-离子对试剂)水溶液-有机溶剂为流动相,分别讨论了背景紫外吸收试剂、检测波长、离子对试剂、有机溶剂、柱温及流速对分离测定吡咯烷阳离子的影响。最佳色谱条件为:以80%(V/V)(0.5 mmol/L对氨基苯酚盐酸盐-0.1 mmol/L庚烷磺酸钠)水溶液-20%(V/V)甲醇为流动相,检测波长230 nm,柱温30℃,流速2.0 mL/min。在此条件下,N-甲基,乙基吡咯烷阳离子、N-甲基,丙基吡咯烷阳离子和N-甲基,丁基吡咯烷阳离子在1.6 min之内基线分离,检出限(S/N=3)分别为0.02,0.03和0.07 mg/L,相对标准偏差(n=5)小于0.4%。将此方法用于分析实验室合成的离子液体样品,加标回收率在97.4%～98.0%之间。本方法快速、简单、准确、可靠,具有良好的实用性。     

基于离子液体的反相液相色谱法检测胆碱和四甲基铵

本文发展了以离子液体为流动相添加剂的反相液相色谱分离和间接紫外检测胆碱和四甲基铵的方法。研究了离子液体、甲醇、紫外检测波长等因素对分离、检测胆碱和四甲基铵的影响。用普通的反相色谱柱，以甲醇/1-丁基-3-甲基咪唑四氟硼酸盐水溶液为流动相，在210 nm紫外检测波长下，实现了胆碱和四甲基铵的分离和检测。本方法对分析物的检出限低于0.5 mg/L,标准曲线具有良好的线性关系。将方法应用于植物生长调节剂和桶装水样品的分析，加标回收率为95.1%～99.6%,相对标准偏差小于2.0%。     

以吡啶离子液体作为流动相添加剂的液相色谱法分析三氟乙酸根与三氟甲磺酸根

发展了用吡啶离子液体作为流动相添加剂的反相液相色谱分离和间接紫外检测三氟乙酸根和三氟甲磺酸根的分析方法。研究了吡啶离子液体、咪唑离子液体、对氨基苯酚盐酸盐和氯化四丁基铵作为流动相添加剂对三氟乙酸根和三氟甲磺酸根的影响,考察了吡啶离子液体的浓度、有机溶剂和检测波长等因素,并讨论了离子液体的作用、保留规律和相关机理。吡啶离子液体在分离检测中起到离子对试剂和紫外吸收试剂的作用。采用反相C_(18)色谱柱,以甲醇-0.3 mmol/L溴化N-己基吡啶水溶液(体积比10∶90)为流动相,在柱温30℃,流速1.0 m L/min,紫外检测波长250 nm条件下,三氟乙酸根和三氟甲磺酸根在12 min内完全分离,检出限分别为0.09、0.18 mg/L。将此法应用于离子液体中三氟乙酸根和三氟甲磺酸根阴离子的测定,加标回收率为96.0%~101%。该方法简单、准确,具有实用价值。     

离子液体作为流动相添加剂的亲水作用色谱-间接紫外检测法分析四丁基磷与四丁基铵

发展了用咪唑离子液体作为流动相添加剂的亲水作用色谱-间接紫外检测四丁基磷和四丁基铵的分析方法。研究了咪唑离子液体、吡啶离子液体作为流动相添加剂对四丁基磷和四丁基铵分析的影响,考察了咪唑离子液体的浓度、有机溶剂含量、检测波长等因素的影响,并讨论了离子液体的作用。采用亲水作用色谱柱,以乙腈-1.0 mmol/L 1-乙基-3-甲基咪唑四氟硼酸盐(体积比60∶40)为流动相,在色谱柱温度30℃,流速1.0 mL/min,紫外检测波长210 nm条件下,四丁基磷和四丁基铵离子在15 min内得到完全分离。检出限为1.0～1.2 mg/L,线性和重现性良好。将此方法应用于松花江水样品和克音河水样品的分析,加标回收率为95.9%～107%。该方法简单,易于应用。     

Ionic liquids as mobile phase additives for determination of thiocyanate and iodide by liquid chromatography

An analytical method was developed for the simultaneous determination of thiocyanate and iodide by reversed‐phase liquid chromatography with UV detection using imidazolium ionic liquids as mobile phase additives. The chromatographic behaviors of the two anions on a C₁₈ column were studied and compared with four types of reagents including imidazolium ionic liquids, pyridinium ionic liquids, 4‐aminophenol hydrochloride and tetrabutylammonium as mobile phase additives. The effects of the concentrations of imidazolium ionic liquids, organic solvents and detection wavelength on separation and detection of the anions were investigated. The role of ionic liquids, retention rules and mechanisms were discussed. The separation of the anions was performed on the C₁₈ reserved‐phase column using acetonitrile‐0.3 mmol/L 1‐amyl‐3‐methylimidazolium tetrafluoroborate (10:90, v/v) as mobile phase, with column temperature of 35°C, flow rate of 1 mL/min and detection wavelength of 210 nm. Under these conditions, the two anions can be completely separated within 6 min. The limits of detection were 0.05 mg/L. The method was applied for the determination of thiocyanate and iodide in ionic liquid samples and iodide drugs, and the spiked recoveries ranged from 97 to 101%. The method is simple, accurate and meets the requirements of quantitative analysis for thiocyanate and iodide.     

Indirect ultraviolet detection of alkaline earth metal ions using an imidazolium ionic liquid as an ultraviolet absorption reagent in ion chromatography

A convenient and versatile method was developed for the separation and detection of alkaline earth metal ions by ion chromatography with indirect UV detection. The chromatographic separation of Mg²⁺, Ca²⁺, and Sr²⁺ was performed on a carboxylic acid base cation exchange column using imidazolium ionic liquid/acid as the mobile phase, in which the imidazolium ionic liquid acted as an UV‐absorption reagent. The effects of imidazolium ionic liquids, detection wavelength, acids in the mobile phase, and column temperature on the retention of Mg²⁺, Ca²⁺, and Sr²⁺ were investigated. The main factors influencing the separation and detection were the background UV absorption reagent and the concentration of hydrogen ion in ion chromatography with indirect UV detection. The successful separation and detection of Mg²⁺, Ca²⁺, and Sr²⁺ within 14 min were achieved using the selected chromatographic conditions, and the detection limits (S /N = 3) were 0.06, 0.12, and 0.23 mg/L, respectively. A new separation and detection method of alkaline earth metal ions by ion chromatography with indirect UV detection was developed, and the application range of ionic liquids was expanded.     

Hydrophilic interaction liquid chromatography with indirect ultraviolet detection for the separation and quantification of pyrrolidinium ionic liquid cations

A method of hydrophilic interaction liquid chromatography with indirect ultraviolet detection was developed to determine three pyrrolidinium ionic liquid cations, i.e. N-methyl-N-ethyl pyrrolidinium cation ([MEPy]⁺), N-methyl-N-propyl pyrrolidinium cation ([MPPy]⁺) and N-methyl-N-butyl pyrrolidinium cation ([MBPy]⁺). Chromatographic separation was achieved on a hydrophilic column using imidazolium ionic liquids and organic solvents as the mobile phase. The effects of the background ultraviolet absorption reagents, the imidazolium ionic liquids, detection wavelength, organic solvents, column temperature and the pH value of the mobile phase on the separation and determination of pyrrolidinium cations were investigated and the retention behaviors in hydrophilic interaction chromatography were discussed. The optimized chromatographic conditions were selected. Under the optimal conditions, the detection limits (S/N = 3) for [MEPy]⁺, [MPPy]⁺ and [MBPy]⁺ were 0.59, 0.53 and 0.46 mg/L, respectively. The method has been successfully applied to the determination of the three ionic liquids synthesized in our chemistry laboratory. This research results may improve the analytical method of ionic liquid cations.     

高效液相色谱法测定涤纶中的间苯二甲酸含量

 涤纶中加入少量的间苯二甲酸对改进涤纶性能有一定的影响。用高效液相色谱法对涤纶样品中的间苯二甲酸的含量进行测定 ,用甲醇和氢氧化钠溶液充分水解样品 ,利用NovaparkC18柱 ,以甲醇 水 (体积比为 15∶85 ,pH 3 )溶液为流动相 ,分析了不同国家和地区的涤纶样品 ,并对最佳水解条件及色谱条件的选择等方面进行了讨论。     

High-performance liquid chromatography utilization of ionic liquids as mobile phase additives for separation and determination of the isomers of amino benzoic acids

For the isomers of amino benzoic acid, including o-, m-, p-amino benzoic acid, the beneficial effects of using the ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIm][BF₄]), as mobile phase additives on retention behavior and separation were investigated. Chromatographic separation of the o-, m-, p-amino benzoic acid was performed on a reversed-phase C18 column by ultraviolet detection at 245 nm. The effects of several chromatographic parameters, concentrations and pH values of [BMIm][BF₄] solutions, methanol concentration and length of alkyl chain on different ionic liquids, on the separation and determination of the isomers were evaluated. The optimized chromatographic conditions were established using an aqueous 0.5 μmol/L [BMIm][BF₄] solution (pH 3.0)/methanol (40:60, v/v) as mobile phase without need of gradient elution, with separation of three amino benzoic acids achieved within four min. The calibration curve showed good linearity over the tested range of 2 mg/L to 120 mg/L for the three isomers with a correlation coefficients of 0.9999. The recoveries of the three amino benzoic acids of spiked components were between 99.8% and 100%. The method has been successfully applied to the determination of p-amino benzoic acid in the pharmaceutical, Bromine Mitag Procaine Injection.     

Imidazolium ionic liquid as the background ultraviolet absorption reagent for determination of morpholinium cations by high performance liquid chromatography-indirect ultraviolet detection

A novel analytical method was developed for determining morpholinium cations lacking ultraviolet absorption groups.This determination was carried out by high performance liquid chromatographyindirect ultraviolet（HPLC-1UV） detection using imidazolium ionic liquid as background absorption reagents,and imidazolium ionic liquid aq.soln.-organic solvent as mobile phase by a reversed-phase C18 column.The background ultraviolet absorption reagents,imidazolium ionic liquids and organic solvents were investigated.The imidazolium ionic liquid in the mobile phase is not only the background ultraviolet absorption reagent for IUV,but also an active component to improve the separation of morpholinium cations.It was found that morpholinium cations could be adequately determined when0.5 mmol/L 1-ethyl-3-methylimidazolium tetrafluoroborate aq.soln./methanol（80：20,v/v） was used as mobile phase with an IUV detection wavelength of 210 nm.In this study,the baseline separation of Nmethyl,ethylmorpholinium cations（MEMo） and N-methyl.propylmorpholinium cations（MPMo） was successfully achieved in 8.5 min.The detection limits（S/N = 3） for MEMo and MPMo were 0.15 and0.29 mg/L,respectively.This simple and practical method has been successfully applied to the determination of two morpholinium ionic liquids synthesized by the chemistry laboratory.     

Analysis of Morpholinium Ionic Liquid Cations by Hydrophilic Interaction Columns Coupled with Indirect UV Detection

A method was developed for the separation and detection of morpholinium ionic liquid cations by hydrophilic interaction column combined with indirect ultraviolet detection using imidazolium ionic liquids as ultraviolet absorbents in high‐performance liquid chromatography. The effects of the ultraviolet absorbents, organic solvents, and the pH value of the aqueous solution in the mobile phase for the determination of morpholinium cations were investigated by using a hydrophilic column with carbamoyl group as the analytical column. The retention and detection behavior of morpholinium cations was discussed. The suitable chromatographic conditions were 0.8 mmol/L 1‐ethyl‐3‐methyl‐imidazolium tetrafluoroborate aqueous solution (pH 3.5 adjusted with acetic acid)/acetonitrile (45/55, v/v) as the mobile phase and a detection wavelength of 210 nm. Under these conditions, the baseline separation of N‐methyl‐N‐ethyl‐morpholinium cation ([MEMo]⁺) and N‐methyl‐N‐propyl‐morpholinium cation ([MPMo]⁺) was successfully achieved in 15 min. The detection limits of [MEMo]⁺ and [MPMo]⁺ were 0.595 and 0.531 mg/L, respectively. Relative standard deviations were less than 0.2%. This method has been successfully applied to the analysis of morpholinium ionic liquid samples synthesized in chemical laboratories, which is simple, reliable, and practical.     

高效液相色谱法测定萨拉沙星

采用高效液相色谱法测定了萨拉沙星。色谱柱为μ－BondapakTMC18柱（3．9mm×300mm）,流动相为V（乙腈）：V（甲醇）：V（2mmol／L磷酸,用三乙胺调pH3．5）＝30：5：65,用二极管阵列检测器检测,检测波长278nm,得到了满意的分离效果。