采用柱切换色谱-离子阱质谱联用法研究复方丹参滴丸中丹参素及其代谢产物

采用柱切换高效液相色谱技术对人血清中的丹参素及其代谢产物进行富集和分离,利用对电喷雾离子阱多级质谱负离子模式进行结构分析。一级流动相为甲醇-水(30：70,V/V),流速0．8mL／min;二级流动相为甲醇-水-甲酸铵(15：85：0．5,V/V/V),流速0．2mL／min;在人血清中检测到丹参素及其代谢产物,并探讨了主要代谢产物乙酰化的丹参素(m/z 240．2)。建立一种复方丹参滴丸中丹参素及其代谢产物在人体内代谢过程的高效分析方法。该方法可用于复方丹参滴丸中丹参素及与其结构类似的其它药物的体内代谢研究。     

液相色谱-质谱法测定纺织品和皮革制品中痕量全氟辛烷磺酸盐

建立了纺织品和皮革制品中全氟辛烷磺酸盐(PFOS)的液相色谱-二级质谱(LC-MS2)测定方法。样品经0.1mol/L HCl和甲醇超声波振荡提取,高效液相色谱分离;色谱柱为Zorbax SB-C18;流动相为V(甲醇)∶V(10mmol/L乙酸铵水溶液)=70∶30,流速为0.3mL/min。采用负离子模式的电喷雾质谱检测。以一级质谱得到的准分子离子m/z499作为母离子,进行二级质谱(MS2)分析。选择MS2的碎片离子m/z169、230、280、330及419定性确证,MS2总离子流色谱(TIC)峰面积定量。实验优化了样品提取方法和色谱、质谱条件,并对二级质谱碎裂机理和特征离子进行了研究。结果表明,本法简便快速,准确可靠,相对标准偏差小于8.6%,回收率在90%~99%之间;检出限为1.5mg/kg,远低于欧盟指令50mg/kg的限量规定。本方法已成功应用于纺织品、皮革制品中痕量PFOS的测定。     

超高效液相色谱-高分辨质谱确证分析泥鳅体内五氯酚代谢物

建立了超高效液相色谱-高分辨质谱(UPLC-HRMS)鉴定泥鳅体内五氯酚代谢物五氯酚磺酸酯的方法。将在低浓度五氯酚下暴露的泥鳅样品粉碎,采用含8%(体积分数)三乙胺的70%(体积分数)乙腈水溶液提取,经混合阴离子交换小柱萃取净化,在ACQUITY BEH C18色谱柱(100 mm×2.1 mm,1.7μm)上分离,采用电喷雾负离子(ESI-)一级质谱全扫描加数据依赖的二级质谱扫描(full mass-ddMS2)模式测定,获得代谢物的准分子离子、同位素离子和二级质谱碎片离子的精确质量数。结果表明,五氯酚在泥鳅体内的代谢以磺化为主,没有发现羟基化和葡萄糖醛酸化。代谢物主要为五氯酚磺酸酯,其含量随着暴露时间(t)的延长逐渐增加,当暴露时间为36 h时达到峰值,随后逐渐减小,当t≥120 h时,五氯酚磺酸酯含量基本维持不变。该方法可用于生物体内五氯酚的代谢研究。     

中药复方六神丸中多类成分的多维液质系统筛查和鉴定

中药复方中成分复杂,通常包含不同类别的多种化合物。因此,建立无靶标的筛查和鉴定中药复方的分析模式是十分必要的。本研究采用液相色谱/飞行时间质谱(HPLC/TOF-MS)和液相色谱/离子阱多级质谱(HPLC/IonTrapMSn)的多维液质联用系统筛查和鉴定中药复方六神丸中的多类化学成分。在优化的液质条件下,飞行时间质谱对六神丸质谱信息中的每个色谱峰进行了精确分子量测定,并匹配出可能的化学组成;再结合离子阱质谱提供的多级碎片结构信息对其进行结构解析,最后采用相应的标准品进行确证。本研究共鉴定出六神丸中分别来源于蟾酥、麝香和牛黄三味药材的25种化合物,为复杂体系的多类别成分分析提供了一种有效、可靠的新模式。     

基于UPLC-Q-TOF MS鉴定复方香薷水化学成分

采用超高效液相色谱-四极杆串联飞行时间质谱（UPLC-Q-TOF MS）技术对中药复方香薷水的化学成分进行快速分析鉴定。通过色谱峰响应程度和分离效果优化复方香薷水的前处理方法和仪器条件;采用Agilent Phe Hex(150 mm×2.1 mm,1.9μm)色谱柱进行分离,以0.1%甲酸水溶液-乙腈为流动相进行梯度洗脱,柱温35℃,流速0.3 mL/min;通过正、负两种离子模式采集复方香薷水的质谱数据,得到精确质量数和二级碎片,结合对照品、Pubchem、安捷伦中药化合物质谱数据库和文献报道等信息对其化合物进行分析鉴定。鉴定出复方香薷水的112个成分,其中黄酮类22个,苯丙素类20个、有机酸18个、萜类14个、生物碱11个、氨基酸5个以及其他类型化合物22个。该研究全面阐述了复方香薷水的化学物质基础,为其质量控制和药效物质研究提供了理论依据。     

高效液相色谱-电喷雾-离子阱质谱法推定硫酸依替米星中有关物质的结构

采用高效液相色谱-电喷雾-离子阱质谱法(HPLC-ESI-IT-MSn)对硫酸依替米星中有关物质结构进行推定.采用Phenomnex Gemini NX C18色谱柱,以水-氨水-冰醋酸(96∶ 3.6∶ 0.4, V/V)-甲醇(70∶ 30, V/V)为流动相,质谱条件:电喷雾离子源(ESI),正离子检测模式;离子源温度350 ℃;雾化氮气压力275.8 kPa;干燥氮气流速10 L/min;离子阱质谱检测器,Smart扫描模式,扫描质量范围m/z 100～900.硫酸依替米星样品中共检出18种有关物质,对其中的13种物质的结构进行了推定,其余5种有关物质的结构未进行解析,只提供了分子量和二级质谱信息.     

液相色谱-串联质谱法分析樟柳碱大鼠肝匀浆代谢产物

运用液相色谱-电喷雾离子阱串联质谱(LC-MSn)联用技术研究了樟柳碱大鼠肝匀浆中的代谢物。采用离体实验的代谢研究方法,将樟柳碱与大鼠肝匀浆在富氧条件下温孵,代谢物以乙酸乙酯萃取,以ReliA-sil C18(5μm,2 mm×150 mm)为分离柱,甲醇/0.01%三乙胺溶液(用甲酸调节pH 3.5)(60∶40,V/V)为流动相,采用LC-MS及LC-MSn等方法进行分析。和原药相比较,根据温孵液中分析物分子量的变化(ΔM)及其多级质谱数据,在樟柳碱的大鼠肝匀浆培养液中鉴定出了2种代谢物,即脱水去甲基樟柳碱和N-氧化樟柳碱。实验结果表明,该液相色谱-串联质谱方法适合于药物代谢物的快速分析。     

柱前衍生化结合LC-MS~n分析人尿中茶碱及其代谢物

采用固相萃取结合化学衍生化的样品柱前预处理方法,利用液相色谱-电喷雾/多级质谱联用技术(LC-ESI/MSn),对人经口服给药后尿液中的茶碱及其代谢产物进行分析,探讨了茶碱、代谢物及相关衍生物的质谱裂解行为,推测茶碱在人体内的代谢途径。尿样经Bond Elute C18小柱固相萃取,收集甲醇洗脱部分在50℃下氮气吹干,以N,N-二甲氨基氯乙烷为衍生试剂进行衍生化。以Shimpack C18为色谱柱、甲醇-水-甲酸(体积比20∶80∶1)为流动相,在正离子模式下对尿样中茶碱、代谢物及其衍生化产物进行LC-ESI/MSn分析。采用上述方法,共分析鉴定了人尿中的茶碱和4种代谢物(1-甲基尿酸、1,3-二甲基尿酸、1-甲基-N-乙酰化物、3-甲基黄嘌呤),其中1种代谢物未见文献报道。在正离子模式下,茶碱及代谢物的二级质谱大多丢失18 u,28 u或57 u片段生成一系列碎片离子,而衍生化产物的二级质谱均有规律地丢失45 u片段生成一系列碎片离子。通过与未经衍生化的尿样比较发现,衍生化可明显增强茶碱、1-甲基尿酸和3-甲基黄嘌呤的质谱检测灵敏度。本研究补充了茶碱在人体内的代谢轮廓,可为灵敏检测生物样本中茶碱、代谢物及其结构类似物提供借鉴。     

副溶血性弧菌细胞猝灭及代谢物组提取方法的优化

以气相色谱-质谱联用(GC-MS)为分析方法,比较了液氮和75%甲醇(-80℃)两种溶液对副溶血性弧菌细胞的猝灭效果,以及氯仿、75%冰甲醇、水、甲醇-氯仿-水(10∶3∶1,V/V)、甲醇-氯仿-水(3∶1∶1,V/V)、甲醇-氯仿(1∶1,V/V)6种提取剂对副溶血性弧菌代谢物组的提取效果。结果表明,用75%甲醇(-80℃)猝灭副溶血性弧菌时,出现了代谢物泄漏现象,而液氮猝灭则不存在这个现象;检索发现,采用75%冰甲醇提取获得了47种代谢物,峰面积标准偏差为8.02%,其它5种提取剂获得代谢物种类少于40种,且重现性差。比较色谱峰数量、面积和重现性后发现,液氮猝灭、75%冰甲醇提取适于副溶血性弧菌代谢物组提取。     

甲基原薯蓣皂苷静脉注射给予大鼠后体内代谢物的LC-MS~n分析

采用液相色谱-多级离子阱质谱法(LC-MSn)法,检测大鼠生物样本中的甲基原薯蓣皂苷(MPD)及其代谢产物,以推测MPD在大鼠体内的代谢途径。对大鼠静脉注射给予40 mg/kg的MPD,并收集尿液、血浆、胆汁和粪便等样本,经固相萃取(SPE)净化提取后,采用Phenomenex Gemini C18色谱柱,以甲醇(B)-水(A)为流动相进行梯度洗脱,流速1.0 mL/min。采用正负离子检测。在生物样本中共检测到14个代谢产物。通过与对照品的色谱行为和多级质谱特征相比对,鉴定了其中6个代谢产物,分别为Protodioscin(M3),26-O-β-D-Glucopyrannosyl-(25R)-furan-5-ene-3β,22α,26-trihydroxy-3-O-α-L-rhamnopyranosyl-(1→2 or 4)-β-D–glucopyranoside(M5),MPD(M0),Pseudoprotodioscin(M7),26-O-β-D-Glucopyrannosyl(25R)-furan-5-ene-3β,26-dihydroxy-22-methoxy-3-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranoside(M9),26-O-β-D-Glucopyrannosyl(25R)-furan-5-ene-3β,26-dihydroxy-22-methoxy-3-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside(M10)和Dioscin(M11)。根据已有对照品的质谱裂解规律,用LC-MSn法推测了另外5个代谢物。其中Protodioscin(PD)和Dioscin是两个主要的代谢产物,其对应的生成途径是MPD在大鼠体内的主要代谢途径。代谢反应总体以一相代谢为主,主要是水解脱糖,同时检出2个二相代谢产物;代谢物结构变化主要发生在糖上,母核均无明显变化。     

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.     

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。     

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.

     

Synthesis of phenolic components of Grains of Paradise

Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.     

恶臭嗅辨实验室建设探讨

针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。     

氯氧化镁生成热的研究

用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。     

Summary of development of the theory of stability of colloids and thin films

In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.     

Study of hydration of two cements of different strengths

Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, M_o, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700^oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.     

解决能源问题的新途径--光解水制氢的研究

面对日益枯竭的能源危机,氢能是一种洁净、最有前景的替代能源。目前在各种制氢的方法中光催化分解水制氢的研究最多,光解水过程中催化剂最关键,本文对利用太阳能光解水的途径、提高光催化反应效率以及光催化剂的开发研究进行了综述。