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高效液相色谱法测定猪尿中克伦特罗对映异构体残留量 总被引:3,自引:0,他引:3
建立了测定猪尿中克伦特罗对映异构体残留量的高效液相色谱分析方法.在碱化的条件下,用乙酸乙酯提取10 mL猪尿样品,提取液经稀HCl反萃取,萃取液直接过SCX固相萃取小柱,再用5%氨化甲醇洗脱,洗脱液经氮气吹干后用200 μL甲醇定容.采用Astec CHIROBIOTICTM V手性色谱柱,以V(甲醇)∶ V(冰乙酸)∶ V(三乙胺)=99.94∶ 0.02∶ 0.04为流动相进行HPLC分析,检测波长301 nm,外标法定量.克伦特罗单-对映体的峰面积与其浓度在70~5000 μg/L范围内呈良好的线性; 线性相关系数均大于0.9996; 猪尿样品中检出限为0.30 μg/L.猪尿中克伦特罗对映体在1.0~20.0 μg/L范围内的添加回收率为76.3%~91.5%; 相对标准偏差RSD均小于7%(n=5). 相似文献
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亲水液相色谱三重四极杆质谱联用法快速检测尿液和血浆中河豚毒素 总被引:2,自引:0,他引:2
建立了快速检测尿液和血浆中河豚毒素的亲水液相色谱三重四极杆质谱联用分析方法.样品经乙腈沉淀、TSK-gel Amide-80亲水色谱柱分离后,采用电喷雾串联质谱多反应监测(MRM)模式检测,基体匹配标准外标法定量.尿液和血浆样品的线性范围分别为3~500 μg/L和1~200 μg/L,加标回收率分别为96%~108%和100%~105%,相对标准偏差小于9%和16%(n=6),样品的检出限分别为1.0和0.3 μg/L(S/N=3).本方法简单、快速、灵敏、特异性强. 相似文献
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根据海洛因和甲基苯丙胺滥用者毛发中毒品及其代谢物的分布特点,通过实验比较了两类毒品滥用者毛发的分析特点。海洛因吸食者毛发采用甲醇超声释放待测物,而后直接调整pH值进行液相萃取,萃取物挥干后进行衍生化并进行GC/MS检测;甲基苯丙胺吸食者毛发在碱性条件下消解,然后采用小体积萃取,直接在提取液中衍生化,并进行GC/MS检测。通过空白毛发标准添加6-单乙酰吗啡、吗啡和可待因进行分析,3种鸦片类毒品最小检测限均小于3μg/g,RSD(n=5)为2.5%~9.6%;通过空白毛发标准添加苯丙胺、甲基苯丙胺、3,4-(亚甲二氧基)苯丙胺和3,4-(亚甲二氧基)-甲基苯丙胺进行分析,4种苯丙胺类毒品的最小检测限为0.05μg/g,RSD(n=5)为5%~14%。 相似文献
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反相离子对色谱-电感耦合等离子体质谱联用技术测定水中痕量Cr(Ⅲ)与Cr(Ⅵ) 总被引:3,自引:0,他引:3
建立了反相离子对色谱(RPIPC)与电感耦合等离子体质谱(ICP-MS)联用技术快速分离测定水中痕量Cr(Ⅲ)和Cr(Ⅵ)的方法.通过考察流动相的pH值、离子对试剂及甲醇的浓度和EDTA的添加等对不同形态铬的保留时间及分离度的影响,确定当流动相组成为2.0 mmol/L TBA,5%(V/V)甲醇,pH=5.5时,Cr(Ⅲ)与Cr(Ⅵ)可达最佳分离.ICP-MS测定时选用碰撞池技术以消除40Ar12C+与35Cl16OH+对52Cr+的谱学干扰;进样100 μL时,Cr(Ⅲ)与Cr(Ⅵ)的检出限分别为0.15 μg/L和0.16 μg/L.加标回收率在93.6%~106.2%之间; RSD<4%(n=3).以本方法分析了某市自来水、雨水及某品牌纯净水中Cr(Ⅲ)与Cr(Ⅵ)的含量,结果令人满意. 相似文献
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提出了高效液相色谱-串联质谱法测定人尿液中鸦片类、苯丙胺类和可卡因类等28种毒品含量的方法。试样用乙酸乙酯提取,离心分离,提取液于40℃氮气吹干后,用甲醇-水(30+70)溶液1mL溶解定容,用高效液相色谱-串联质谱检测。28种毒品的质量分数均在2.0~200μg·kg-1范围内呈线性关系,方法的检出限(3S/N)在1.0~2.0μg·kg-1之间。在空白尿液样品中加入5,10,50μg·kg-1混合标准溶液,测得28种毒品的回收率在61.0%~117%之间,相对标准偏差(n=6)在3.0%~14%之间。 相似文献
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根据海洛因和甲基苯丙胺滥用者毛发中毒品及其代谢物的分布特点,通过实验比较了两类毒品滥用者毛发的分析特点。 海洛因吸食者毛发采用甲醇超声释放待测物,而后直接调整pH值进行液相萃取,萃取物挥干后进行衍生化并进行GC/MS检测;甲基苯丙胺吸食者毛发在碱性条件下消解,然后采用小体积萃取,直接在提取液中衍生化,并进行GC/MS检测。 通过空白毛发标准添加6-单乙酰吗啡、吗啡和可待因进行分析,3种鸦片类毒品最小检测限均小于 3 μg/g,RSD(n=5)为2.5%~9.6%;通过空白毛发标准添加苯丙胺、甲基苯丙胺、3,4-(亚甲二氧基)苯丙胺和3,4-(亚甲二氧基)-甲基苯丙胺进行分析,4种苯丙胺类毒品的最小检测限为0.05 μg/g,RSD(n=5)为5%~14%。 相似文献
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液相色谱-氢化物发生-原子荧光联用同时测定洛克沙胂及其代谢物 总被引:4,自引:0,他引:4
利用液相色谱-氢化物发生-原子荧光联用技术同时检测5种砷形态化合物(亚砷酸、砷酸、一甲基胂酸、二甲基胂酸和洛克沙胂).结果表明,在梯度洗脱条件下,以C18反相柱作分离柱,含0.5 mmol/L四丁基溴化铵的NaH2PO4-CH3OH溶液为流动相,5种砷化合物得以完全分离;以20 g/L K2S2O8为氧化剂进行紫外消解,7% HCl为载流,20 g/L KBH4为还原剂,砷化合物形成最佳的原子荧光信号.5种砷化合物在一定的浓度范围内与荧光峰面积呈良好的线性关系; 检出限<10 μg/L; 加标回收率为81.4%~105.6%; 相对标准偏差RSD<4.0%.本方法适用于饲料、鸡粪、土壤和植物样品中洛克沙胂及其代谢物(亚砷酸、砷酸、一甲基胂酸和二甲基胂酸)的含量分析. 相似文献
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利用手持技术改进测定乙醇分子结构实验 总被引:1,自引:0,他引:1
利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。 相似文献
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由于石化行业的生产需要,其材质的使用具有多样性和广泛性,经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识,根据光谱仪的测试能力及标样的采集,实现了一个或几个元素测量范围的扩展,并对其测量的影响因素进行了研究。 相似文献
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V. I. Bol'shakova L. I. Demenkova É. N. Shmidt V. A. Pentegova 《Chemistry of Natural Compounds》1989,24(6):691-694
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988. 相似文献
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Mustafa R. Ibrahim Zacharia A. Fataftah Paul von Ragu Schleyer Peter D. Stout 《Journal of computational chemistry》1987,8(8):1131-1138
Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases. 相似文献
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V. I. Bol'shakova L. I. Demenkova É. N. Shmidt V. A. Pentegova 《Chemistry of Natural Compounds》1988,24(6):691-694
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae. 相似文献
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Influence of viscosity of medium on processes of oxygen quenching of excited states of mesoporphyrin
E. I. Kapinus V. A. Ganzha B. M. Dzhagarov E. I. Sagun V. B. Pavlenko 《Theoretical and Experimental Chemistry》1989,25(2):146-151
The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989. 相似文献
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The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted
indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator
model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was
established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing
analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997. 相似文献