多种植物油中黄酮和角鲨烯分布UPLC研究

该文采用超高效液相色谱(UPLC)技术分别建立植物油中黄酮类物质和角鲨烯的定量方法,考察常见13种植物油中黄酮和角鲨烯的分布规律。实验采用70%的甲醇预处理植物油样,制备供试品溶液;经Acquity UPLC的C18柱(2.1 mm×100 mm,1.7μm)分离,以甲醇和0.8%磷酸溶液分别为流动相A相和B相,经梯度洗脱,于360 nm处,分离检测黄酮类组分。采用正交试验优化出植物油中角鲨烯的最佳皂化条件,经Acquity UPLC的C8柱(2.1 mm×100 mm,1.7μm),流动相为乙腈-水(97:3),于波长210 nm分离检测角鲨烯。结果表明:所建方法能有效分离黄酮组分或角鲨烯,在黄酮浓度50~600 ng/m L范围内5种黄酮各自线性关系良好(r≥0.999),检测限和定量限为10.2~15.6 ng/m L和33.6~48.6 ng/m L,平均加样回收率在97.75%~102.21%,重复性(RSD)为2.79%~7.75%;在角鲨烯浓度1~350μg/m L范围内;角鲨烯的线性相关良好(r≥0.999),检测限和定量限分别为27.3 ng/m L和81.9 ng/m L,平均加样回收率为88.18%,重复性RSD为1.96%;13种植物油中能检出角鲨烯,其中橄榄油中最高;只有火麻籽油和沙棘油中检出所列5种黄酮,亚麻籽油检出槲皮素和木犀草素,橄榄油中检出木犀草素和异鼠李素;所建立方法是食用植物油中黄酮类组分或角鲨烯质量控制的好方法,提示植物油的生产工艺可能影响极性黄酮类组分的含量。     

山茶油中功能性成分的测定

目的:为了测定山茶油中的4类功能性组分的含量。方法:采用分光光度法测定茶皂素、茶多酚的含量,气相色谱法测定角鲨烯和维生素E的含量。结果:试验结果表明橄榄油包含的角鲨烯和茶皂素最多,分别为540.03mg/100g和12.26mg/g;山茶油A和山茶油B包含茶多酚最多,分别为41.21μg/g和41.63μg/g,山茶油B包含的维生素E最多,为23.93mg/100g。结论:综合比较得知山茶油茶多酚含量最高。     

精炼吊瓜籽油的脂肪酸分析

对压榨吊瓜籽毛油进行了精炼,计算出得率为54%。采用GC分析、比较了吊瓜籽精油、橄榄油和菜籽油的脂肪酸组分,表明吊瓜籽油中油酸、亚油酸含量为8.48%、33.6%,亚油酸含量高于橄榄油(8.48%)和菜籽油(13.03%).经过GC-MS确证,吊瓜籽含有丰富的角鲨烯(22.7%),是营养保健物质的新型来源.     

紫外分光光度法测定面粉中的过氧化苯甲酰

本文基于在酸性条件下,过氧化苯甲酰(BPO)能把Fe2 氧化成Fe3 ,再与邻菲罗啉发生褪色反应,建立了紫外分光光度法测定面粉中过氧化苯甲酰的方法.测定过氧化苯甲酰线性范围为1.0 ×10-7g/mL-3.2×10-6g/mL和3.2 ×10-6g/mL～2.4×10-5g/mL,检出限6.0×10～g/mL,对8.0 ×10-7g/mL过氧化苯甲酰连续11次测定的相对标准偏差RSD为4.2%,已用于面粉中过氧化苯甲酰的测定.     

用于食用油的高阻隔抗UV功能的泡罩包装

目的 为开发一种用于食用油的高阻隔抗紫外线(UV)功能片材,用于小容量食用油的泡罩包装,便于携带且方便一次性使用.方法 研究基于高阻隔塑料乙烯-乙烯醇共聚物EVOH,通过多层共挤和多层复合技术,得到一种4层结构的高阻隔片材CPP/APET/PE-EVOH/PE,通过电子万能试验机和气体透过率测定仪对片材的力学性能、水蒸气透过率、氧气透过率进行测定,并通过不同材料对比分析该材料在食用油包装中对食用油货架期的影响.结果 结果表明,片材的力学性能优异,水蒸气透过量为2.0 g/(m2.24 h),氧气透过量为0.6 cm3/(m2·24 h·0.1 MPa).该材料用于食用油包装,在温度45℃、相对湿度50％条件下贮存30d后,橄榄油过氧化值的变化量为1.22 mmol/kg,远低于GB/T 23347-2009《橄榄油、油橄榄果渣油》中特级初榨橄榄油的上限值(10 mmol/kg).结论 该高阻隔抗UV功能的泡罩包装可用于食用油包装,可减缓食用油氧化变质,并保留食用油原有香味.     

三种不同方法测定室内空气中甲醛含量的比较

目的:用酚试剂分光光度法、乙酰丙酮分光光度法和4-氨基-3-联氨-5-巯基-1,2,4-三氮杂茂(AHMT)分光光度法三种方法测定空气中甲醛,通过比较测得的甲醛数据,找出3种方法优劣.方法:用5 mL蒸馏水作为吸收液采样空气样,取(1～5)mL样量按三种方法分别检测出5mL吸收液中甲醛量,再除以采样体积,计算出空气中甲醛浓度.结果:三种方法线性关系良好,相关系数均大于0.9990,BY400160标准水样用三种方法测定的甲醛结果为酚试剂法1.49mg/L,乙酰丙酮法1.50mg/L,AHMT法1.51mg/L,标准水样参考值(1.49±0.07)mg/L.三种方法的相对标准偏差:酚试剂分光光主法(2.23～3.83)％,乙酰丙酮分光度法(1.64～2.84)％,AHMT分光光度法(3.80～4.36)％.结论:三种方法的线性宽、灵敏度好、检出限低、精密度和准确度令人满意,能精准测定室内空气中甲醛.     

GC-MS法对13种植物油中甾醇和脂肪酸的分布研究

该文建立GC-MS法对植物油中的甾醇和脂肪酸含量进行测定,研究常用植物油中甾醇和不饱和脂肪酸的分布规律。采用程序升温法,由安捷伦毛细管GC柱HP-5MS UI(30 m×0.250 mm×0.25μm)和HP-88(60 m×0.250 mm×0.2μm)分离植物油中的甾醇和脂肪酸。结果表明,植物油经皂化,正己烷提取后进样分析,在24-420μg/mL的范围内菜籽甾醇等5个甾醇的线性关系良好(R=0.999 1～0.999 5),检测限在1～2μg/mL; 13种植物油中均检出β-谷甾醇(含量79.54～6 185.42 mg/kg),均未检出菜籽甾醇和麦角甾醇,其中橄榄油和小麦胚芽油中无豆甾醇,牡丹油和山茶籽油中无菜油甾醇。13种植物油均富含不饱和脂肪酸(76%～92%),同时含有较丰富的多不饱和脂肪酸(PUFA)的ω-3系和ω-6系,可按比例调配食用,补充机体修复所需。所建立的GC-MS检测法可快速灵敏地适用于植物油中的甾醇类和脂肪酸类组分的定量分析。     

大田软海绵酸荧光偏振免疫分析方法研究

设计使用荧光试剂PDAM与大田软海绵酸单(OA)反应合成了荧光标记物,并在OA单克隆抗体的基础上建立TOA荧光偏振免疫(FPIA)检测方法.该FPIA方法检测限为4.6 ng/mL,检测范围为7.0-88.7 ng/mL.IC(50)为24.9 ng/mL.本方法操作简单、稳定,有望应用于高通量筛查牡蛎样品中OA含量.     

柱前衍生气相色谱法分离手性二醇类化合物

本文建立了柱前衍生气相色谱法分离1,3-丁二醇、2,3-丁二醇、2,5-己二醇和3,6-辛二醇4种二醇类化合物的手性分离方法。分别使用N-甲基-N-(三甲基硅烷)三氟乙酰胺和三氟乙酸酐为衍生剂与二醇化合物反应,生成相应的衍生物,用CP-Chirasil-Dex CB色谱柱分离二醇对映体,采用分流进样方式,检测器为氢火焰离子化检测器(FID)。在选定的色谱条件下,四种手性化合物分别在2.50～8×10³μg/mL、1.30～8×10³μg/mL、3.5～1×10⁴μg/mL、5～1×10⁴μg/mL范围内呈线性关系,相关系数分别为0.9994、0.9997、0.9990和0.9971,手性分离度均达到2以上,检测限分别为0.8μg/mL、0.4μg/mL、1.8μg/mL、2.5μg/mL。该方法适用于生物酶催化反应所生成的(2R,3R)-2,3-丁二醇、(R)-1,3-丁二醇、(2S,5S)-2,5-丁二醇和(3S,6S)-3,6-辛二醇的检测以及酶促反应过程的监控。     

柱前衍生HPLC-UV法测定氯氮平片中乳糖的含量

采用1-苯基-3-甲基-5-吡唑啉酮(PMP)为衍生试剂,建立柱前衍生高效液相色谱法准确测定氯氮平片中乳糖的含量.实验结果显示,在0.0604～0.3997 mg/mL范围内,衍生目标物的峰面积与乳糖质量浓度呈现良好的线性关系,线性相关系数R2为0.9994,加标回收率在96.7％～99.2％之间,定量限为0.32μg/mL.随机抽选3个批次氯氮平片仿制样品进行检测,乳糖含量分别是42.09,43.36,43.45 mg/片,实测含量与处方含量的偏差不超过2.0 mg/片,结果完全满足氯氮平参比制剂中乳糖含量的检测需要.与现有的检测方法相比较,所提方法具有专属性强、灵敏度高、结果准确可靠等优点,可为氯氮平一致性评价处方的开发提供数据支持,有利于加快仿制药的开发速率和成功率.     

顶空气相色谱/质谱法分析大豆油中正己醛含量

建立大豆油中正己醛含量的顶空气质分析方法。将大豆油试样放入密封的气化瓶中,在55℃温度下,使正己醛气化达到平衡时,取液上气体注入GC/MS,经非极性毛细管柱HP-5ms分离,质谱选择离子监测对正己醛进行定量测定。该方法在0.05~1.00μg/mL范围内线性关系良好,相关系数0.9997;最小检测限为3.15ng/mL,方法回收率在90.0~107%之间,相对标准偏差3.4%。该方法前处理简单、快速,定量准确,灵敏度高,可用于实验室检测大豆油中正己醛含量。     

丁香罗勒油气相色谱与气质联用分析

目的:建立丁香罗勒油中丁香酚的含量测定方法和鉴定挥发性化学成分。方法:气相色谱法,4mm×2m不锈钢柱,10％SE—30为固定液,Chromosorb WAW 60～80目担体,FID检测器,柱温110℃,水杨酸甲酯为内标物;气质联用,以HP—5毛细管柱,柱温起始120℃保持5min后以5℃/min升温至150℃保持7min,检测质荷比范围10～425。结果:丁香酚在2～10mg/ml范围内具良好线性关系,平均回收率为100.08％,RSD为0.95％;气质联用鉴定了39个化合物。结论:方法简便,快速,准确,可排除其它成分的干扰。     

肉桂油气相色谱与气质联用分析

目的:建立肉桂油中桂皮醛的含量测定方法和鉴定挥发性化学成分。方法:气相色潜法,3mm×4m不锈钢柱,10％PEG-20M为固定液,Chromosorb WAW 60-80目担体,FID检测器,柱温190℃;气质联用,以HP-5毛细管柱,柱温起始120℃保持5min后以5C/min升温至150(保持7min,检测质荷比范围10-425。结果:桂皮醛在2-10mg/mL范围内具良好线性关系,平均回收率为99.98％,RSD为1.3％,气质联用鉴定了39种化合物。结论:方法简便,快速,准确,可有效排除其它成分的干扰。     

水浮莲叶挥发性化学成分的GC/MS法分析

采用气相色谱-质谱联用方法(GC/MS)分析了水浮莲叶中挥发性化学成分。以水蒸气蒸馏法从水浮莲叶中提取挥发油,以毛细管柱为分离柱,在最佳分析条件下共分离出30个化合物,用归一化法测定其相对含量,并用气相色谱-质谱法对分离出的化学成分进行鉴定,共鉴定了26个成分,占挥发油总成分的95·20%。该法对挥发油化学成分的分离效果满意。     

Migration of Tinuvin P,a UV stabilizer,from PET bottles into fatty‐food simulants

Tinuvin P migration from Polyethyleneterephthalate (PET) bottles was investigated using several fatty‐food simulants such as olive oil, soybean oil, n‐heptane and iso‐octane, at exposure conditions of 2–10 days at 40°C (total immersion). The stability of several UV stabilizers (BHT, Cyasorb UV 5411, Tinuvin P, Tinuvin 326 and Tinuvin 327) in n‐heptane and iso‐octane was also studied. After 10 days at 40°C, losses of 6% and 10% in iso‐octane and n‐heptane respectively, were verified for Tinuvin P. Other UV stabilizers at the same experimental conditions showed higher losses (up to 30% for Tinuvin 327). These results confirm that, when carrying out specific migration studies, the stability of the substance of interest should be established in the food simulant to avoid underestimating the real migration behaviour. In order to quantify UV stabilizer migration, n‐heptane and iso‐octane solutions were concentrated and directly analysed by SIM mode GC–MS. For olive and soybean oils, Tinuvin P was isolated using size‐exclusion chromatography and quantified by SIM mode GC–MS. Iso‐octane proved to be a more suitable fatty‐food simulant than n‐heptane for the migration study of Tinuvin P from PET. Higher levels of Tinuvin P migrated to olive and soybean oils rather than to n‐heptane. These results suggest that the MERCOSUL recommended official methods for specific migration studies should be revised, since the migration levels using n‐heptane as a fatty‐food simulant could be underestimated when compared to edible oils. Copyright © 1999 John Wiley & Sons, Ltd.     

GC/MS with post-column switching for large volume injection of headspace samples: sensitive determination of volatile organic compounds in human whole blood and urine

When volatile or semivolatile compounds are measured by headspace (HS) gas chromatography (GC)/mass spectrometry (MS), the maximum gas volume to be injected is usually 0.5-1.0 mL; over the volume, the MS detector automatically shuts down due to impairment of the vacuum rate of the MS ionization chamber. To overcome the problem, we modified the gas flow routes of a new type of GC/MS instrument to create a postcolumn switching system, which can eliminate the large volume of gas before introduction of target compounds into the MS ionization chamber. Our HS-GC/MS system enabled injection of as large as 5 mL of HS gas without any disturbance. As the first example analysis, we tried to establish the analysis of naphthalene and p-dichlorobenzene in human whole blood and urine by this method with large volume injection. The limits of detection for both compounds in whole blood and urine were as low as about 10 and 5 pg/mL, respectively. The validation data and actual measurements were also demonstrated. The new GC/MS system has great potential to analyze any type of volatile or semivolatile organic compounds in biological matrixes with very high sensitivity and full automation.     

液液萃取-GC/MS法分析地表水中的多氯联苯

建立了液液萃取-GC/MS联用分析地表水中的多氯联苯的方法,并对实际水样进行了测定。各目标物的线性回归R值均大于0.999,MDL为0.08-3.9ng/L,RSD为0.25%-6.2%,回收率为87.6%-113%。     

猪肉中二溴磷残留量的气相色谱和气相色谱/质谱分析

试样经盐酸酸化,用正己烷提取残留的二溴磷。提取液在-20℃冷冻2小时凝固析出脂肪,净化液经浓缩定容后,用配有电子俘获检测器的气相色谱测定(GC-ECD),外标定量,并用气相色谱—质谱(选择离子监测)(GC/MS(SIM))进行确证。以HP-5大口径毛细管柱和HP-5MS毛细管柱为分离柱,选择出合适的色谱条件,二溴磷的分离效果良好。本方法对猪肉样品的测定低限为0.05mg/kg;添加浓度为0.05mg/kg～1.00mg/kg时,回收率为89％以上;相对标准偏差小于5.0％;标准进样量在0.1～10.0ng范围内,线性关系良好,r=0.9995。样品前处理采用了微量化学法(MiccM)技术,质谱(选择离子监测)确证的监测离子选m/z 301、185、109amu。     

Determination of parabens and triclosan in indoor dust using matrix solid-phase dispersion and gas chromatography with tandem mass spectrometry

A simple sample preparation method for the determination of four parabens and triclosan in indoor dust is presented. Analytes were extracted from the sample and isolated from interfering species using the matrix solid-phase dispersion technique. After that, they were silylated and determined by gas chromatography combined to tandem mass spectrometry (GC/MS/MS). The influence of several factors on the yield and selectivity of the extraction was evaluated in detail. Under final working conditions, samples (0.5 g) were mixed with the same amount of anhydrous sodium sulfate and dispersed on 1.25 g of C18. This blend was transferred to the top of a polypropylene cartridge containing 2 g of Florisil. After removing less polar species with 10 mL of dichloromethane, analytes were recovered using 10 mL of acetonitrile. This extract was concentrated to 1 mL, derivatized, and injected in the GC/MS/MS system. Derivatization was carried out at 45 degrees C in 5 min using 100 microL of N-methyl-N-(tert-butyldimethylsilyl) trifluoroacetamide. Quantification limits from 0.6 to 2.6 ng/g and absolute recoveries between 80 and 114% were achieved. Analysis of dust samples demonstrated the presence of the target species in indoor dust from private houses. The highest average concentration (702 ng/g) corresponded to triclosan.