猪肝脏和肌肉组织中β-兴奋剂克伦特罗的高效液相色谱电喷雾质谱分析研究

建立了猪肉和肝组织中克伦特罗的高效液相色谱电喷雾质谱(HPLC—ESI／MS)分析方法。在最佳色谱条件下克伦特罗的保留时间为16min,样品空白无干扰。定量分析的线性范围为2—100mg／L;最低检出限为0．75mg／L;方法回收率为95％-98％;RSD小于2．0％。利用ESI／MS／MS对β-兴奋剂克伦特罗进行了质谱解析,选择特征离子峰m／z277、259和203作为准确定性的依据。对实际生物样品猪瘦肉和肝进行检测结果表明,当样品中克伦特罗残留含量较高时,可以利用紫外检测数据对其进行准确定量。当残留含量低于最低检出限时,可以根据HPLC／ESI／MS结果中有无特征峰出现,给出较准确的定性结果。     

高效液相色谱-串联质谱联用测定富含淀粉食品中丙烯酰胺

以甲基阿烯酰胺作为内标物，用高效液相色谱／串联质谱（HPLC／MS／MS）法测定食品中的丙烯酰胺。均质后的食品样品，加入正己烷经液-液分配去除脂肪，用蒸馏水提取丙烯酰胺，Carrez试剂净化提取样品，净化液经离心后过0．45μm微孔滤膜，采用HPLC／MS／MS电喷雾电离（ESI），阳离子，多反应监测（MRM）模式检测，外标法定量。方法的线性范围为2～500μg／L，线性相关系数为0．9997，检出限为2μg／kg；高中低3个水平的加标回收率分别为99．4％、99．6％和98．4％；相对标准偏差（RSD）均小于7．8％。     

HPLC-APCl（＋）MS／MS分析动物源性食品中的硝基咪唑类药物残留量

运用高效液相色谱-大气压电离串联四极杆质谱（HPLC-APCI（＋）MS／MS）内标法分析动物源性食品中多种硝基咪唑类（nitroimidazoles）药物——甲硝唑（MNZ）、地美硝唑（DMZ）、替硝唑（TNZ）、洛硝唑（RNZ）的含量。样品添加氘代标示物HMMNI—D^3、IPZ—OH—D^3后，用乙腈提取，通过OASIS HLB C18 SPE柱净化，Waters Sunfire C18色谱柱分离，采用梯度洗脱，流动相为0．1％甲酸水溶液和0．1％甲酸乙腈溶液；大气压电离源正离子MRM模式检测：MNZ m／z 172．0／82．1，172．0／128．0；DMZ m／z 142．0／81．1，142．0／96．1；TNZ m／z 248．0／121．0，248．0／93．1；RNZ m／z 201．0／140．0，201．0／110．0；IPZ—OH—D^3m／z189．0／125．0，189．0／171．0；HMMNI—D^3m／z161．0／58．0，161．0／143．1。方法定量下限（LOQ，S／N〉10）0．2μg／kg，在质量浓度0．2—25．0μg/L范围内，峰面积与质量浓度成良好线性（r〉0．9991）。     

花生及其制品中多种霉菌毒素残留同时测定方法

利用液相色谱-质谱联用（LC-MS／MS）建立了花生及其制品中多种霉菌毒素包括黄曲霉毒素（B1,B2,G1,G2）、赭曲霉毒素A、伏马毒素B1、脱氧雪腐镰刀菌烯醇、T-2毒素、HT-2毒素及玉米赤霉烯酮的同时测定方法。样品经PBS溶液和甲醇-水溶液提取,提取液经稀释、过滤后,用免疫亲和柱净化,通过淋洗去除免疫亲和柱上的杂质,随后用洗脱液过柱,将目标物分离下来,氮吹干后定容。以液相色谱-质谱／质谱测定,外标法定量。方法的检出限黄曲霉毒素B1为0．0005mg／kg,黄曲霉毒素B2,G1,G2为0．001mg／kg,赭曲霉毒素A为0．002mg／kg,伏马毒素B1为0．020mg／kg,脱氧雪腐镰刀菌烯醇为0．050mg／kg,T-2毒素为0．010mg／kg,HT-2毒素为0．010mg／kg,玉米赤霉烯酮为0．002mg／kg。在样品中添加检出限水平的毒素混标溶液,加标回收率为72．35％-97．82％,测定结果的相对标准偏差为8．95％～18．41％（n=10）.     

高效液相色谱-串联质谱法测定不同畜禽配合饲料中伏马毒素的含量

为摸清复杂基质中FB1和FB2污染的准确水平,本研究建立了高效液相色谱-串联质谱法( LC-MS/MS)测定不同畜禽配合饲料中伏马毒素B1(FB1)和B2(FB2)的分析方法。样品用乙腈-水(50：50, V/V)提取, MAX强阴离子固相萃取柱富集净化后,以0.1%甲酸和甲醇为流动相,经 Thermo C18色谱柱(100 mm ×2.1 mm,5μm)分离,采用电喷雾正电离(ESI+)多反应模式(MRM)监测,外标法定量。结果表明：不同饲料样品中FB1和FB2在1~500μg/kg之间线性关系良好,相关系数(R2)均大于0.9990,定量限分别为0.098和0.197μg/kg,检出限分别为0.328和0.656μg/kg;低、中、高浓度加标回收率为89.7%~95.1%,相对标准偏差(RSD)为3.2%~8.6%。用本方法对市场上采集的106份不同畜禽配合饲料中FB1和FB2含量进行测定,样品检出率为98.11%。本方法适用于基质复杂的畜禽配合饲料中伏马毒素FB1和FB2的准确、快速定性与定量分析。     

血清中葡萄糖的测量比对-ID-LC—MS／MS法

利用同位素稀释-液相色谱-质谱法-（ID-LC-MS／MS）准确测定血清中葡萄糖含量。以[13C6]葡萄糖为内标,用重量法准确地与血清混合,离心沉淀蛋白后在碱性条件下与1．苯基-3-甲基-5-吡唑酮反应,以ZORBAXRX-SIL色谱柱分离,以乙腈-水（体积此25：75）为流动相,使用电喷雾三重四极杆串联质谱多重反应监测模式（MRM）测定,同位素稀释的括号法进行定量。采用美国NIST的血清标准物质SRM965b进行了确证,并用该方法参加JCTLM关于血清中葡萄糖含量的国际比对,测量值与均值的相对偏差分别为1．1％（A样）．1．8％（B样）,结果在等效范围内。     

高效液相色谱-电喷雾三级四极杆质谱测定鸡肉组织中氯霉素残留的研究

建立了鸡肉组织中氯霉素残留的液相色谱-电喷雾质谱联用(LC—ESI—MS—MS)测定法。采用微量化前处理方法,省去固相萃取步骤,以m／z321．0为母离子,m／z152．1、257．0和194．1为子离子,采用多反应监测(MRM)负离子模式对鸡肉组织中的氯霉素残留进行检测、方法的检出限为0．010μg／kg(S／N≥3),定量下限为0．10μg／kg,线性范围为0．100～1．00μg／L,加标回收率为74．3％～84．0％,相对标准偏差(n=6)为7．9％～12．7％。该法具有操作简便、有机试剂消耗量少、测定周期短等优点。     

高效液相色谱-质谱法分析测定水中氨基甲酸酯

采用固相萃取-高效液相色谱-质谱法（LC／MS）检测研究了水中氨基甲酸酯农药残留。水样用固相萃取富集净化,环己烷＋乙酸乙酯（1＋1）洗脱;以甲醇-10mmol／L乙酸铵为梯度流动相,Symmetry C18柱高效液相色谱分离。电喷雾正离子模式,选择质子化氨基甲酸酯分子离子[M＋H]^＋为定量离子进行MS测定。结果表明,6种氨基甲酸酯组分的平均加标回收率为73．5％～89．8％;相对标准偏差为4．50％～12．6％;水样浓缩至1／2500后的检出限为0．8～3．2ng／L。本法具有非常高的选择性、灵敏度和准确度,完全能满足水中痕量氨基甲酸酯农残的高灵敏分析。     

高效液相色谱-串联质谱法同时测定烟用香精香料中16种邻苯二甲酸酯类化合物北大核心CSCD

采用液相色谱-串联质谱（LC—MS／MS）联用技术建立了烟用香精香料中16种邻苯二甲酸酯类化合物的测定方法。样品经超声萃取、离心后,用DionexACCLAIMC18色谱柱（150×3mm,3μm）分离,以水溶液一甲醇溶液为流动相,采用梯度洗脱方式,以电喷雾离子源正离子多反应监测模式进行分析检测。方法的定量限（S／N-10）为0．28～37．5ng／mL,线性范围为50～1000ng／mL,样品加标回收率在78．9％～119．3％范围,相对标准偏差（RSD）为2．5％～16．6％。方法成功应用于烟用香精香料中邻苯二甲酸酯类化合物的检测。     

高效液相色谱/质谱分析抱茎獐牙菜提取物中的苷性成分

采用高效液相色谱／质谱法（HPLC／MS）分析抱茎獐牙菜提取物中5种苷性成分。在C18柱上,以甲醇（A：含20％水）和水（B：含10％甲醇）为流动相,流速1mL／min,线性梯度洗脱B从100％到0％,35min,液相色谱-质谱质联用（LC／MS）,大气压化学电离源（APCI）,对其中5种苷性成分进行定性鉴定。经HPLC／APCIMS分析确证,抱茎獐牙菜提取物中含有獐牙菜苦苷（swertiamarin）、龙胆苦苷（gentiopicroside）、獐牙菜苷（sweroside）、异红草苷（isoorientin）和獐牙菜山酮苷（swertianolin）。采用外标法定量,回收率分别为98．3％、106．7％、92．3％、88．2％和107．3％,该方法简便、快速、准确。     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.