毛细管超临界流体色谱的进展

根据超临界流体的特点,评述了毛细管超临界流体色谱在仪器、应用方面的最新进展及其发展前景。     

超临界流体色谱在手性分离中的应用

综述了超临界流体色谱在手性分离中的应用,讨论了3类手性固定相、二元流动相、三元流动相和温度对分离的影响。对超临界流体色谱的手性分离中的应用作了展望。     

超临界流体色谱法测定柴油芳烃含量

采用超临界流体色谱法,测定柴油中单环和多环芳烃的含量。芳烃加标回收实验测定结果的回收率在97.5%~101.6%之间。单环和多环芳烃的重复性实验的测定结果最大偏差不超过0.4个单位。与质谱法分析的数据对比,两种方法的线性相关系数可达到0.99以上。     

超临界流体色谱法测定固体在二氧化碳中的溶解度

开发了一种测定超临界二氧化碳中大分子溶质的溶解度的方法。这一方法将微型超微界流体萃取直接与超临界色谱相耦合，超临界流体色谱采用ＦＩＤ作为检测器。实验中两者具有同一压力、温度及同样的ＣＯ２流速度。     

超临界流体的应用现状

超临界流体技术是近年来发展迅速的一项新技术,有着广泛的应用前景。本文综述了其在分离、分析及材料制造方面的应用现状。     

超临界流体色谱纯化青蒿素的研究

将超临界流体色谱技术应用于青蒿萃取液中青蒿素的提纯。采用ZorBaxSB-C18色谱柱(9.4mm×250mmI.D.,5μm),在改性剂含量约0%～10%,CO2流速6～30g·min·1,压力10～16MPa,温度313.15～338.15K范围内考察了青蒿素的纯化效果,确定了较适宜的色谱提纯条件为:CO2流速22g·min·1,柱温313.15K,柱压11MPa;此条件下提纯青蒿提取液,得到的产品纯度为74.83%(wt)。研究了提纯过程中的保留值规律,将青蒿素的容量因子与密度和温度的关系进行了关联,计算值和实验值的平均相对偏差为6.002%,二者吻合较好。     

超临界流体的应用与研究进展

综述了超临界流体的基础理论研究及其在分离提纯、材料制备、化学反应、环境保护和分析化学等方面的应用。     

超临界流体技术应用及进展

简要介绍了超临界流体的基本性质,综述了超临界流体技术在精细化工、食品工程、医药工程、环境工程、高分子加工、材料制备以及分析化学中的应用。     

Lipidomics by Supercritical Fluid Chromatography

This review enlightens the role of supercritical fluid chromatography (SFC) in the field of lipid analysis. SFC has been popular in the late 1980s and 1990s before almost disappearing due to the commercial success of liquid chromatography (LC). It is only 20 years later that a regain of interest appeared when new commercial instruments were introduced. As SFC is fully compatible with the injection of extracts in pure organic solvent, this technique is perfectly suitable for lipid analysis and can be coupled with either highly universal (UV or evaporative light scattering) or highly specific (mass spectrometry) detection methods. A short history of the use of supercritical fluids as mobile phase for the separation oflipids will be introduced first. Then, the advantages and drawbacks of SFC are discussed for each class of lipids (fatty acyls, glycerolipids, glycerophospholipids, sphingolipids, sterols, prenols, polyketides) defined by the LIPID MAPS consortium.     

拟除虫菊酯类农药在超临界流体色谱中的对映体分离

[目的]获得单一对映体对于低毒高效的农药生产和环境安全具有重要意义。[方法]使用超临界CO2色谱,对6种拟除虫菊酯类农药在Sino-Chiral OJ柱上进行对映体分离研究,考察了改性剂种类(甲醇、乙醇和异丙醇)及体积分数(1%、3%、5%)对其分离的影响。[结果]高效氯氟氰菊酯在3种改性剂条件下都得到了基线分离;氯菊酯只在甲醇作为改性剂时得到分离;氰戊菊酯只在3%乙醇改性条件下实现部分分离;氯氰菊酯在乙醇作为改性剂时取得了最优分离,得到8个异构体中的7个出峰;联苯菊酯和溴氰菊酯均只得到2个对映体出峰。[结论]在手性分离过程中,对映体与手性固定相之间的偶极-偶极和π-π作用对菊酯类农药的分离起较大作用,同时卤素取代基的电负性大小对分离也有较大影响。     

5种芳氧苯氧丙酸类除草剂的超临界色谱手性分离

[目的]获得单一的高效异构体对于提高农药药效和减少环境污染具有重要意义。[方法]采用Sino-ChiralOJ柱在超临界色谱中以CO2为流动相对5种芳氧苯氧丙酸类除草剂进行手性分离。探索了系统温度(25-45℃)、流动相改性剂(甲醇、乙醇或异丙醇)及添加量(5%-15%)对分离效果的影响。[结果]唑禾草灵、吡氟禾草灵、喹禾灵获得了完全分离,其最大分离度分别为11.66、1.48、8.34,而禾草灵酸和吡氟氯禾灵均未获得分离。[结论]随着改性剂添加量的增大,唑禾草灵、吡氟禾草灵、喹禾灵的容量因子和分离度逐渐减小,而分离因子基本保持不变。在同一改性剂添加量下,容量因子按甲醇-乙醇-异丙醇的顺序基本逐渐增大,而分离因子基本保持不变。随着系统温度的升高,容量因子逐渐增大,分离因子和分离度逐渐减小。各物质结构上的差异导致分离效果不同。     

Thermodynamic Study of Enantioseparation of Mitotane by Supercritical Fluid Chromatography

Enantioseparation data of mitotane (o,p′-DDD) have been obtained and thermodynamically analyzed. A diallyl-L-tartardiamide-based stationary phase (Kromasil CHI-TBB column) was used for chiral separation and CO₂ added to 14% of methanol at 160 bar was used as mobile phase in a temperature range of 303.15–313.15 K. The thermodynamic parameters accounting for the retention and the separation were determined by means of van't Hoff plots. The isoenantioselective temperature was calculated to be 331.55 K. The enantioseparation process was enthalpically driven under experimental conditions.     

超临界流体色谱纯化Z-藁本内酯的研究

将超临界流体色谱技术应用于当归挥发油中Z-藁本内酯的提纯。采用ZorBax SB-C18色谱柱(250 mm×9.4 mm I.D.,5μm),分别考察了改性剂、流速、压力、温度对色谱分离过程的影响,确定了较适宜的色谱提纯条件:CO2流速10 g·min-1,柱温313.15 K,柱压14 MPa;在此工艺条件下提纯制备Z-藁本内酯单体,得到的产品纯度为98.5%(wt)。研究了色谱过程的热力学规律,绘制色谱分离过程的van’t Hoff曲线,并由此得到了色谱相转移过程焓变为21.46kJ·mol-1,并比较了Z-藁本内酯与相邻组分从流动相到固定相分配过程中焓变和熵变的差值,在此条件下Z-藁本内酯色谱分离过程为焓控过程。     

超高效液相色谱法测定烟草料液中7种水溶性糖

以ACQUITY UPLC BEH Amide柱为分析柱,乙腈(0.2%TEA)-水作为流动相,建立了超高效液相色谱-蒸发光散射检测器测定烟草料液中鼠李糖、木糖、果糖、甘露糖、葡萄糖、蔗糖、麦芽糖7种水溶性糖的分析方法。7种水溶性糖回归方程相关系数均大于0.999,检出限在0.56～1.11μg/mL之间,回收率在96.7%～103%之间,相对标准偏差在0.78%～3.08%之间。该方法操作简便、分析速度快、重复性好、准确性高,可用于烟草料液中水溶性糖含量的测定。     

超临界流体色谱法制备高纯度EPA-EE和DHA-EE

以二氧化碳作流动相,分别以极性相反的C18柱和硅胶柱为固定相,用超临界流体色谱法分离二十碳五烯酸乙酯(EPA-EE)和二十二碳六烯酸乙酯(DHA-EE)。比较C18柱和硅胶柱分离EPA-EE和DHA-EE的机理和分离效果,提出结合C18柱和硅胶柱的超临界流体色谱制备高纯度EPA-EE和DHA-EE的方法。     

Supercritical Fluid Extraction and Chromatography of Lipids in Bilberry

A supercritical fluid extraction (SFE) method has been developed for the extraction of lipids in bilberry. Experimental design was used to optimize pressure, temperature and extraction time using CO₂ as solvent. Best SFE condition for total lipids was 450 bar, 60 °C and 45 min. The SFE method was compared to conventional Bligh & Dyer (B&D) extraction. The amount of fatty acid methyl esters (FAME) was found to be 4.84 ± 0.06 mg and 4.564 ± 0.003 mg per g of the freeze‐dried bilberry sample for the developed SFE and B&D methods, respectively, while the amount of total lipids was found to be 54.40 ± 6.06 mg and 65.70 ± 0.67 mg per g of sample for SFE and B&D, respectively. This discrepancy between FAME and total lipids could be explained by the presence of wax esters, sterol esters, carotenoids and phospholipids, as determined by supercritical fluid chromatography.