超高压液相色谱-串联质谱法测定畜禽粪便中3种β-受体激动剂残留

建立了畜禽粪便中3种β-受体激动剂药物残留的超高压液相色谱-串联四极杆质谱联用仪测定方法。样品酶解后经高氯酸溶液净化,调节p H值至碱性,乙酸乙酯提取,净化浓缩后以流动相定容,用超高压液相色谱-质谱联用仪检测,内标法定量。3种β-受体激动剂在0.5~20.0μg/L范围内线性关系良好,相关系数均大于0.998。畜禽粪便中3种β-受体激动剂的加标回收率为80.3%~110.2%,相对标准偏差为3.0%~7.7%,检出限(S/N=3)为0.04~0.07μg/kg。     

固相萃取-超高效液相色谱-串联质谱法测定畜禽饮用水中23种抗生素和3种β-受体激动剂

建立了固相萃取-超高效液相色谱-串联质谱同时测定畜禽饮用水中4类23种抗生素(磺胺类、喹诺酮类、四环素类、氯霉素类)和3种β-受体激动剂(克伦特罗、莱克多巴胺、沙丁胺醇)的分析方法。样品经高氯酸调节pH至5.0,加入乙二胺四乙酸二钠(Na2EDTA),HLB固相萃取柱富集,用超高效液相色谱-质谱联用仪分时段多反应监测离子模式分析,外标法定量抗生素,内标法定量β-受体激动剂。23种抗生素和3种β-受体激动剂的空白基质加标回收率为50.7%~104.6%,相对标准偏差(n=3)为2.6%~8.8%。23种抗生素和3种β-受体激动剂的线性关系良好,相关系数均大于0.994,检出限为0.01~0.20 ng/L。通过该方法分析了北京地区36家规模化畜禽养殖场畜禽饮用水中的抗生素和β-受体激动剂,检出了多种抗生素,并对含量进行了定量计算。     

液相色谱-四极杆飞行时间质谱法筛查猪肉中5类26种药物残留

建立了同时筛查测定猪肉组织中氟喹诺酮类、磺胺类、有机磷类、β-激动剂类、四环素类5类26种药物残留的液相色谱-四极杆飞行时间质谱分析方法。试样采用QuEChERS前处理方法,样品经酸化乙腈-甲醇(1%乙酸,10%甲醇)提取。提取液以C18分散剂和正己烷净化,氮吹浓缩、定容后过滤膜上机检测。液相色谱以甲醇-水(0.1%甲酸)作为流动相梯度洗脱,C18色谱柱分离;高分辨质谱采用正离子模式检测,以二级质谱特征离子定性,以分子离子精确质量数提取色谱峰面积定量。结果表明26种药物的定量下限为0.4~10μg/kg;加标回收率为56.7%~106.2%,相对标准偏差(RSD)为7.7%~15.8%。方法操作简单、快速、高效,可作为猪肉中26种药物残留的快速筛查检测方法。     

食品中甜味剂的检测技术研究进展

食品中甜味剂对人体健康有重要影响,因此日益受到人们的关注,需要建立针对食品中甜味剂的检测方法。对2008年以来食品中甜味剂的检测方法液相色谱、液相色谱–质谱、气相色谱–质谱、光谱等分析方法进展进行了综述。     

液相色谱-电喷雾电离质谱法检测尿液中的3种合成类固醇药物

研究建立了合成类固醇药物群勃龙、四氢孕三烯炔酮和孕三烯酮的液相色谱-电喷雾质谱的检测方法。尿样经过β-葡萄糖醛酸酶酶解和叔丁基甲醚提取后,采用Zorbax SB-C18分析柱(150 mm×2.1 mm,5 μm),在流动相为pH 3.5的甲酸铵缓冲液-乙腈的条件下进行梯度洗脱,在正离子模式下检测。考察了不同的质谱条件对这类化合物检测结果的影响。建立了人尿液中合成类固醇药物的液相色谱-电喷雾电离质谱的初筛和确证方法。     

液相色谱–质谱联用技术在水产品兽药残留检测中的应用

液相色谱–质谱联用技术逐渐成为水产品中兽药残留检测的重要手段。从技术原理、样品处理方法的改进和新方法的应用,以及多兽药残留同时分析等方面论述了液相色谱–质谱联用技术在水产品兽药残留检测中的应用与进展。     

盐酸二甲双胍药物中杂质测定方法研究进展

对近年来盐酸二甲双胍类药物中杂质的测定方法进行综述.盐酸二甲双胍类药物中的杂质主要有双氰胺、二甲胺以及由二甲胺形成的亚硝胺类基因毒性杂质等.测定方法主要有高效液相色谱(HPLC)法、离子色谱(IC)法、高效液相色谱–串联质谱(HPLC–MS/MS)法和气相色谱–串联质谱(GC–MS/MS)法,其中高效液相色谱法主要用于...     

微囊藻毒素检测方法研究进展

综述了目前国内外微囊藻毒素检测方面的各种研究方法及成果,对高效液相色谱(HPLC)、液相色谱串联质谱(LC–MS)、气相色谱串联质谱(LC–MS)、毛细管电泳(CE)、薄层色谱(TLC)、生物法和生物化学法等检测方法存在的优缺点进行了评述,并展望了该研究领域的未来发展趋势。     

乳制品中兽药多种类残留的液相色谱-质谱分析研究进展

近年来,乳制品安全问题备受关注,兽药残留作为化学危害的一个重要部分使得针对其检测技术的研究一直是乳制品安全分析的热点领域,液相色谱-质谱技术因在灵敏度和选择性方面的优势已成为目前兽药残留分析的主流技术。基于液相色谱-质谱技术的兽药残留分析趋势已逐渐在向多种类、多组分发展,但由于兽药各种类之间在理化性质、残留状态、限量要求等方面差异较大,导致在样品前处理和仪器分析环节存在一定的技术困难。为进一步了解该技术领域的研究进展,该文从样品前处理、色谱-质谱检测和基质效应等方面对近几年采用液相色谱-质谱技术测定乳制品中兽药多种类残留的国内外文献进行了综述。     

饮用水中有机污染物检测方法研究进展

介绍水中有机污染物的富集方法如顶空法、萃取法、固相微萃取法、液相微萃取法、棒吸附萃取等,对饮用水中有机污染物的检测技术如气相色谱法、气相色谱–质谱联用法、液相色谱法、液相色谱–质联用法等进行了综述并对检测技术的发展趋势进行了展望。     

利用手持技术改进测定乙醇分子结构实验

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。     

光谱仪测试范围的扩展

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。     

Influence of viscosity of medium on processes of oxygen quenching of excited states of mesoporphyrin

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.     

Dichroism of absorption and polarization of phosphorescence of molecules of the closed form of nitrobenzospirothiopyran

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.     

Determination of heats of detonation and influence of components of composite explosives on heats of detonation of high explosives

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

     

物质分配系数的测定实验改进

实验教学目的是从解决实际问题出发,以实验技术训练和实验设计思想培养为目标。介绍了将单一的物质分配系数测定实验改进为综合实验,提高了实验效果及实验资源利用率。     

Neutral diterpenoids of oleoresins of five species of conifers of Transcarpathia

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.     

Calculation of enthalpies of hydrogenation of hydrocarbons

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.     

非那雄胺合成工艺改进

非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。