HPLC—ECD法检测小鼠体内多巴胺及其代谢产物

建立了HPLC-电化学检测法同时测定小鼠血浆及脑组织中多巴胺及其代谢产物的方法。采用安捷伦水相柱，流动相为V（甲醇）＋V（水）=10＋90，其中水相中含NaH2PO4·H2O，KCl，EDTA，辛烷磺酸钠，流量0．25mL·min^-1。，检测电压0．52V。结果表明，线性范围：多巴胺（DA）25～750ng，多巴烯（DOPAC）25～750ng，高香草酸（HVA）50～1000ng，线性关系与精密度良好；该法操作简单、快速、准确，可用于检测小鼠血浆及脑组织中多巴胺及其代谢产物的含量。     

反相高效液相色谱法同时测定人血浆中的西诺沙星和萘啶酸

提出了同时测定人血浆中的西诺沙星和萘啶酸的高效液相色谱方法。采用反相C18柱、254nm紫外检测,乙腈－甲醇－0．01mol/L草酸（30：5：65,V／V;pH4．55）体系,实现了二者的良好分离。分别考察了磷酸缓冲溶液和草酸缓冲溶液作为流动相弱溶剂,结果草酸缓冲溶液能有效改善峰形、降低检测限。在不同pH值（pH2．80,4．08,4．55）进行了实验,pH4．55获得最佳分离,最低检测量分别为0．14ng（西诺沙星）和0．24ng（萘啶酸）,比文献报道的同类药物最低检测量低10倍。     

超高效液相色谱-串联质谱法测定注射用头孢曲松钠中2-巯基苯并噻唑的含量

建立了一种超高效液相色谱-串联质谱法（UPLC-MS/MS）测定注射用头孢曲松钠中2-巯基苯并噻唑（MBT）基因毒性杂质含量。样品经甲醇提取,50%(V/V)乙腈稀释后,采用ACQUITY UPLC HSS T3色谱柱（2.1 mm×100 mm, 1.8μm）分离,乙腈-0.05%(V/V)乙酸（80∶20, V/V）为流动相,电喷雾离子源（ESI）,多反应监测（MRM）负离子模式扫描,外标法定量。MBT在0.11～10.92 ng/mL范围内线性关系良好（r2=0.9989）,检出限为0.03 ng/mL,定量限为0.08 ng/mL,平均回收率为96.8%,相对标准偏差（RSD）不大于3.5%。采用该方法检测抽检的14个厂家63批次样品中MBT杂质含量,59批次样品中有MBT检出。该方法适用于注射用头孢曲松钠中MBT的定性和定量分析。     

高效薄层扫描法测定蛛网膜下腔出血患者脑脊液中血小板活化因子

摘要：建立了测定蛛网膜下腔出血患者（SAH）脑脊液中血小板活化因子（PAF）质量浓度的高效薄层扫描方法。薄层板为高效硅胶G板（100mm×l00mm）,展开剂为V（氯仿）:V（甲醇）:V（水）=65:35:6,下层液展开,显色剂为100g/L磷钼酸溶液,展开距90mm,扫描波长630nm。方法的线性范围0.5～2.5μg/L,相关系数0.9990,最小检测质量浓度50ng/L,平均回收率98.6％。运用所建立的方法测定了16例SAH患者发病后脑脊液和10例非神经系统疾病患者脑脊液中PAF的质量浓度及其变化     

使用限进介质色谱柱的柱切换高效液相色谱法直接进样测定大鼠血浆中舒必利

提出一种直接进样测定大鼠血浆中舒必利浓度的高效液相色谱方法,使用限进介质色谱柱作为预柱在线去除血浆蛋白后,将舒必利通过柱切换转移到分析柱中进行分析。限进介质色谱柱为CAPCELLPAKMFSCX阳离子交换柱（20×4．0mmi．d．,5μm）,分析柱为Kromasil C18柱（150×4．6mm i．d．,5μm）,限进介质柱预分离时流动相为PH=6．88的50mmol／L磷酸盐缓冲液乙腈（100：5,V／V）,切换后分析流动相为PH=6．83的50mmol／L磷酸盐缓冲液-乙腈（100：10,V／V）。流速均为1mL／min,检测波长为240nm。该方法检出限为17ng／mL,定量限为50ng／mL。舒必利在50～1400ng／mL之间线性良好（r=0．9997）,高中低浓度的日内、日间相对标准偏差分别为1．5％～4．2％及2．0％～5．2％,方法回收率为98．8％～104．1％．     

复合维生素片剂中泛酸钙的反相高效液相色谱法测定

用十八烷基硅烷键合硅胶为填充剂,以V（水）：V（甲醇）：V（H3PO4）=950：50：1为流动相,检测波长为210 nm,采用反相高效液相色谱法分离测定了两种复合维生素片剂中的泛酸钙,实验回收率在99.2%～103.4%之间,相对标准偏差RSD为0.6%～1.0%（n=5）,检出限为41 ng.已用于复合维生素片剂中泛酸钙的测定.     

高效液相色谱法测定烟草料液中的糖

研究了用蒸发光散射检测器检测，高效液相色谱法测定烟草料液中糖的方法。料液中的糖用固相萃取预分离，然后以Waters carbohydrate高效糖柱为固定相，V（乙腈）：V（水）=70：30作为流动相分离，蒸发光散射检测器检测；样品中鼠李糖、木糖、阿拉伯糖、果糖、甘露糖、葡萄糖、蔗糖、麦芽糖8种糖的加标回收率分别为：97．0％、95．6％、102％、102．1％、95．0％、101．8％、102．6％、97．8％；线性范围分别为：鼠李糖、果糖、葡萄糖、蔗糖0．1～20pg，木糖、阿拉伯糖、甘露糖、麦芽糖0．2～25μg。相对标准偏差均小于3．2％。方法的检出限达：鼠李糖20ng、木糖26ng、阿拉伯糖28ng、果糖14ng、甘露糖20ng、葡萄糖10ng、蔗糖12ng、麦芽糖15ng，用该方法测定了烟草料液中的糖。     

高效液相色谱法测定银杏外种皮中银杏酸的含量

建立了反相高效液相色谱法测定银杏外种皮中银杏酸含量的方法，色谱柱为Inertsil ODS-2，流动相为甲醇-3%Hac溶液（92:8，V/V），流速1.0mL/min；柱温40℃；紫外检测波长310nm；线性范围：0.572-10.30цg（相关系数R=0.9999）；检测限5.2ng(3a)。银杏外种皮提取物经一步硅胶柱层析预处理。实验测得银杏外种皮中银杏酸含量为5.46%；平均回收率为97.5%，RSD为1.9%(n=6)。该方法简便、准确、线性范围宽。     

基质固相分散-加速溶剂萃取-气相色谱法测土壤中有机氯农药残留

建立了用弗罗里硅土作基质固相分散剂的加速溶剂萃取、并以灭蚁灵（Mirex）为内标的快速、同时测定土壤中16种有机氯农药的气相色谱法。加速溶剂萃取仪在100℃,10．3Mpa用正己烷和丙酮（1：1,V／V）静态提取样品10min,0．01μg/g加标水平回收率为77．3％-101．3％;方法检出限为0．01—0．04ng／g。方法满足了土壤中有机氯农药残留测定的要求。对我国南方不同地域的72个土壤样品进行了测定,大部分有机氯农药在土壤中都有一定检出量,其中环氧七氯最高（2．6～844．5ng／g）,甲氧DDT（23．2—219．8ng／g）和P,P’-DDT（4．0—183．1ng／g）次之,而o,P＇-DDT在72个土样中都没有检出。     

吸附伏安法测定纯铝中痕量钛

在盐酸溶液中，钛（Ⅳ）与钽试剂（BPHA）络合物在－0．3V（vs．SCE）或开路情况下吸附于玻璃碳电极表面，在－0．3－－0．8V范围内以250mV.s^-1进行扫描溶出，峰电位为－0．57V，钛（Ⅳ）浓度在1－35ng.ml^-1(-0.3V)下富集2min和0.06-2ng.ml^-1（开路富集4min）范围内与峰电流呈良好的线性关系，体系选择好，灵敏度高，操作简单，用于纯铝中痕量钛的测定，重现性好，结果准确。     

非水反相液相色谱法测定枸杞子中β-胡萝卜素含量

应用甲醇－乙酸乙酯（５０５５,Ｖ／Ｖ）为流动相,在ＯＤＳ反相柱上采用外标法测定了３种不同产地枸杞子中β－胡萝卜素的含量。方法简便、快速,重现性好。β－胡萝卜素的检测线性范围为１．０～５．０ｍｇ／Ｌ,ｒ＝０．９９９８,平均回收率为９７．１％,变异系数为１．９％。     

极大螺旋藻中β-胡萝卜素的分离纯化及定量测定

 极大螺旋藻 (Spirulinamaximum)中含有多种营养物质 ,其中 β 胡萝卜素具有重要的应用价值。利用 β 胡萝卜素极性小的特点 ,用丙酮 甲醇 (体积比为 7∶2 )溶液对其提取后皂化。采用石油醚萃取 ,通过氧化铝柱进行色谱分析 ,用反相高效液相色谱法 (RP HPLC法 )测定了 β 胡萝卜素的含量。方法准确性高、重现性好 ,平均回收率为96 8%。     

Simultaneous determination of vitamin A and beta-carotene in dietary supplements by liquid chromatography

Several liquid chromatography (LC) methods for analysis of vitamin A in foods and feeds have been previously reported but only a few have been applied in non-food matrixes. A validated LC method is needed for determination of vitamin A and beta-carotene in the various matrixes presented by dietary supplements. The performance of a reversed-phase method with methanol-isopropanol gradient elution was evaluated with standard retinyl derivatives and beta-carotene. The reversed-phase method is capable of separating retinol from other derivatives such as retinyl acetate, retinyl palmitate, and beta-carotene. Two types of extraction were used to extract the analytes from the dietary supplements: a hexane-methylene chloride extraction for soft-gel capsules containing beta-carotene, and a direct solvent extraction for dietary supplements in tablet form. The direct solvent extraction consisted of treatment with ethanol and methylene chloride following addition of hot water (55 degrees C). Results with the reversed-phase method for vitamin A and beta-carotene in the products examined (n = 8) indicated excellent method performance. The main form of vitamin A or beta-carotene in dietary supplements was the all-trans isomer. The reversed-phase method avoids saponification and is rapid, accurate, precise, and suitable for simultaneous determination of retinyl derivatives and beta-carotene in dietary supplements.     

Serum and plasma beta-carotene levels measured with an improved method of high-performance liquid chromatography

An isocratic high-performance liquid chromatographic method specifically developed to allow simple and rapid determination of beta-carotene concentrations in serum and plasma is reported. Using a method modified from a previously published technique, serum and plasma proteins are denatured by exposure to perchloric acid, and beta-carotene is subsequently extracted into an organic matrix consisting of ethyl acetate-tetrahydrofuran (1:1); no evaporation step is required. Separation is achieved using isocratic elution from a reversed-phase C18 column with UV detection at 436 nm. Recovery of beta-carotene from water and plasma was greater than 98.1%; beta-carotene was stable in the extraction matrix for at least 4 h. Three anticoagulants (oxalate, citrate, and EDTA) caused losses of beta-carotene; perchloric acid and tetrahydrofuran could also destroy beta-carotene under certain conditions. Each run required less than 15 min; within-day coefficient of variation for identical samples averaged 2.3%, between-day coefficient of variation was 4.4% and sensitivity was better than 10 ng/ml. Stability of beta-carotene in plasma was also examined. This method permits a simple, rapid, sensitive, precise, and accurate determination of beta-carotene using 0.5 ml of serum or heparinized plasma.     

Solid-phase microextraction coupled with liquid chromatography for determination of beta-carotene in food

beta-Carotene in vegetables and nutritional products is analyzed using solid-phase microextraction (SPME) coupled with liquid chromatography (LC) to improve the speed of analysis and to reduce the consumption of organic solvents. The relative standard deviations (RSDs) of this analytical method for beta-carotene determinations in vegetables and nutritional products are approximately 10% and 5%, respectively. The amount of beta-carotene was found to vary from 0.35 +/- 0.05 ppm to 76.5 +/- 6.9 ppm for several vegetables in Taiwan. This method was linear over the range of 0.4-40 ppm with correlation coefficients higher than 0.997. The experimentally determined level of beta-carotene in nutritional products varied from 3.8 +/- 0.2 ppm to 24.6 +/- 1.1 ppm following SPME-LC. The recoveries of beta-carotene for these measurements following SPME were all higher than 97% +/- 2% (n = 3). The detection limits of beta-carotene for this method were from 0.027 to 0.054 ppm. Conventional solvent extractions take approximately 4-6 h for extraction and reconcentration but SPME takes approximately 1 h. From several tens to hundreds of milliliters, organic solvents can be saved using SPME. SPME provides better analyses on beta-carotene than conventional solvent extraction for nutritional products in terms of speed, precision, simplicity, and solvent consumption.     

Development of a simplified method for the simultaneous determination of retinol, α-tocopherol,and β-carotene in serum by liquid chromatography–tandem mass spectrometry with atmospheric pressure chemical ionization

A new and simple method for the determination of fat-soluble vitamins (retinol, alpha-tocopherol, and beta-carotene) in human serum was developed and validated by using liquid chromatography-tandem mass spectrometry with atmospheric pressure chemical ionization (LC-APCI-MS-MS). Different solvent mixtures were tested to obtain deproteinization and extraction of the analytes from the matrix. As a result, a volume of 240 microL of a 1:1 (v/v) ethanol/ethyl acetate mixture added to 60 microL of serum was found to be suitable for both protein precipitation and antioxidants solubilization, giving the best recovery for all three analytes. Deproteinized samples (20 microL) were injected after dilution, without the need for concentration or evaporation to dryness and reconstruction of the sample. Vitamins were separated on a C-8 column using a 95:5 (v/v) methanol/dichloromethane mixture and ionized in the positive-ion mode; detection was performed in the selected-reaction monitoring mode. Linearity of the LC-APCI-MS-MS method was established over 5 orders of magnitude for retinol and alpha-tocopherol, whereas in the case of beta-carotene it was limited to 4 orders. Lower limits of quantitation were 1.7, 2.3, and 4.1 nM for retinol, alpha-tocopherol, and beta-carotene, respectively. Serum concentrations of retinol, alpha-tocopherol, and alpha+beta-carotene determined in a group of healthy volunteers were 2.48, 38.07, and 0.50 microM, respectively, in samples collected in winter ( n=122) and 2.69, 45.88, and 0.90 microM during summer ( n=66).     

Quantitative analyses of beta-carotene and retinol in serum and feces in support of clinical bioavailability studies

Among more than 50 provitamin carotenoids, beta-carotene is the most metabolically active source of retinol. Despite diets rich in fruits and vegetables containing beta-carotene, vitamin A deficiency is the leading cause of blindness and childhood mortality in developing countries. In addition, the uncertainty of beta-carotene bioconversion into vitamin A suggests that new data are needed to update the nutritional guidelines in developed countries. Previously, we reported the development of a carotene/retinol plateau isotopic enrichment method (CarRet PIE) for the determination of beta-carotene bioavailability and bioconversion into retinol, which utilizes positive ion atmospheric pressure chemical ionization (APCI) liquid chromatography/mass spectrometry (LC/MS). While seeking to validate the CarRet PIE using a mass balance approach requiring fecal measurements of beta-carotene and retinol, interference was encountered that required substantial modifications of the LC/MS assay. Here we report a new LC/MS assay that is based on the detection of molecular anions of beta-carotene using negative ion APCI with a reversed-phase C30 column for HPLC separation. Sample preparation required saponification to eliminate interfering triglycerides. The limit of detection (LOD) of beta-carotene was 0.25 pmol calculated on the basis of an injection of 20 microL of 0.0125 microM beta-carotene, and the limit of quantitation (LOQ) was 1.0 pmol based on the injection of 20 microL of 0.050 microM beta-carotene. The linear range was 1.1 to 2179 pmol on-column. The wide linear range and low LOD and LOQ of this assay facilitated the sensitive and selective quantitative analysis of beta-carotene in both serum and fecal samples in support of an on-going clinical investigation of beta-carotene bioavailability and bioconversion into vitamin A.     

反相高效液相色谱法同时测定番茄中5种类胡萝卜素

用反相高效液相色谱法同时测定了番茄中的α－胡萝卜素、β－胡萝卜素、γ－胡萝卜素、番茄红素及斑蝥黄素。采用１１（Ｖ／Ｖ）丙酮－石油醚混合液直接提取,提取液减压蒸干后,用甲醇溶解,经μ－ＢｏｎｄａｐａｋＣ１８色谱柱,以乙腈－二氯甲烷－甲醇（８５１０５）为流动相,在４５０ｎｍ下进行检测,其保留时间依次为１５．２５,１６．１２,１２．８７,１０．３８和５．３７ｍｉｎ,最小检出限分别为０．２５,０．２２,０．１８,０．１４和０．０５ｍｇ／Ｌ。     

Photovoltaic properties of Au/beta-carotene/n-Si organic solar cells

Photovoltaic properties of Au/beta-carotene/n-Si organic solar cells characterized by current-voltage and capacitance-voltage measurements have been investigated. The photocurrent in the reverse direction increases with increasing illumination intensity. The I(sc) increases linearly with light intensity. The I(sc) dependence of light intensity follows a power law I(sc) approximately F(alpha). The exponent alpha was found to be 1.38. This indicates a monomolecular recombination in this device. Au/beta-carotene/n-Si organic solar cells give an open-circuit voltage of 0.316 V and a short-circuit current of 2.33 x 10(-4) A at light intensity of 6 W/m(2). The best conversion efficiency for Au/beta-carotene/n-Si solar cells was found to be 23.3% at a light intensity of 6 W/m(2).     

Isolation and Determination of Beta-Carotene in Carrots by Magnetic Chitosan Beta-Cyclodextrin Extraction and High-Performance Liquid Chromatography (HPLC)

Beta-carotene is a carotenoid with strong antioxidant activity that has been used in many areas and attracted significant attention. Among the articles reported, however, there are few examples of the convenient and eco-friendly use of magnetic chitosan biopolymers to extract beta-carotene. This paper reports the ultrasonic-assisted solid phase extraction of beta-carotene. The beta-carotene in carrot samples was extracted using synthesized magnetic chitosan beta-cyclodextrin biopolymers prior to high-performance liquid chromatography (HPLC) detection. Under the optimal conditions, the beta-carotene content of carrot was found to be 41.06?±?0.02?μg/g. This newly developed method using magnetic chitosan cyclodextrin biopolymers is a promising method for the ultrasonic-assisted solid phase extraction of carotenoids from vegetables because the procedure is facile and rapid and the magnetic biopolymers can be removed using simple process.