移液枪头式整体柱直接固相微萃取-高效液相色谱法测定尿液中苯二氮卓类药物

本文采用甲基丙烯酸2-羟乙酯(HEMA)与乙二醇二甲基丙烯酸酯在移液器枪头中共聚制备固相微萃取整体柱，用于直接处理尿液中3种苯二氮卓类药物(BZDs)。实验考察了单体用量、聚合时间及固相微萃取条件对BZDs萃取效率的影响，评价了其吸附性能。当HEMA用量为40 mg,聚合温度60℃时，固相微萃取整体柱对目标物吸附效率达98.9%～100%,且对尿液中杂质的吸附率低于10%。取3 mL尿液样品，无需处理，直接上样至该柱，经4 mL纯净水冲洗，1 mL乙腈洗脱，得到的样品结合高效液相色谱仪分析。方法对3种BZDs在2.5～1 000 ng/mL浓度范围呈现良好线性关系(r=0.999),检出限(S/N=3)和定量限(S/N=10)为0.8～1.5 ng/mL和2.5～5.0 ng/mL,回收率为86.2%～107%。本方法构筑的萃取柱制备简单，能实现对原始尿液的直接、高效萃取，操作便捷。     

固相萃取-反相高效液相色谱法测定水中的邻苯二甲酸酯

建立了固相萃取-反相高效液相色谱法检测水中3种邻苯二甲酸酯类物质邻苯二甲酸二甲酯、邻苯二甲酸二(2-乙基己基)酯、邻苯二甲酸二正辛酯的方法. 考察了固相萃取柱、洗脱溶剂、洗脱体积、上样速度以及洗脱速度对萃取效率的影响. 通过综合分析, 选定SupelcleanLC-18 SPE Tube固相萃取柱, 甲醇为洗脱剂, 洗脱体积2 mL, 上样速度为4 mL/min, 洗脱速度为1 mL/min. 在此萃取条件下, 萃取回收率在83.4%～121.2%之间. 邻苯二甲酸二甲酯、邻苯二甲酸二(2-乙基己基)酯、邻苯二甲酸二正辛酯质量浓度在2～100 mg/L之间均为线性. 经萃取后, 方法的最低检出限分别为邻苯二甲酸二甲酯0.06 μg/L, 邻苯二甲酸二(2-乙基己基)酯0.16 μg/L, 邻苯二甲酸二正辛酯0.08 μg/L. 方法的精密度在10%～15%之间. 应用该方法测定自来水中酞酸酯类化合物的含量, 加标回收率为83.6%～110.2%.     

固相萃取-气质联用测定水环境中痕量多环麝香

建立了固相萃取-气质联用法测定水中佳乐麝香(HHCB)和吐纳麝香(AHTN)这两种主要的多环麝香的方法.利用Oasis HLB固相萃取小柱预处理水样,通过对固相萃取条件的优化,得出了最佳实验条件:洗脱溶剂为正己烷,洗脱体积为10mL,水样中添加体积分数0.5%甲醇作为有机改性剂,控制上样流速为5～10mL/min,洗脱速率为0.5～2mL/min.该方法线性相关性好,相对标准偏差在1.67%～5.48%之间,对两种多环麝香的方法检测限均为0.025μg/L.利用该方法对污水处理厂进出水中多环麝香进行测定,佳乐麝香和吐纳麝香的去除率分别为61.3%和51.6%.     

聚苯乙烯-聚4-乙烯基吡啶复合微球的制备及用于检测碱性橙类食品违禁色素

采用可逆-加成断裂链转移（RAFT）无皂乳液聚合法,制备了聚苯乙烯-聚4-乙烯基吡啶（PS@P4VP）复合微球,将其作为固相萃取材料,应用于碱性橙类食品违禁色素的检测,探究了该微球的吸附性能与最佳固相萃取条件,建立了方便面酱料中3种碱性橙类色素的检测方法。结果表明,该微球对碱性橙2、碱性橙21和碱性橙22的最佳吸附pH均为9.0,最佳吸附材料浓度分别为0.9, 0.7和1.5 mg/mL,吸附平衡时间分别为1, 3和60 min。3种色素的吸附过程均符合Langmuir等温吸附模型,最大吸附容量分别为102.04, 129.87和27.47 mg/g。实际样品分析表明,相比于碱性橙22,所制得的PS@P4VP复合微球更适合于碱性橙21和碱性橙2的分析检测,加标回收率为83.2%～95.0%。     

聚[2-(丙烯酰氧基)乙基]三甲基氯化铵-乙二醇二甲基丙烯酸酯整体柱固相萃取结合高效液相色谱法测定尿液中3种苯二氮■类药物

以[2-(丙烯酰氧基)乙基]三甲基氯化铵(DAC)为单体,乙二醇二甲基丙烯酸酯(EDMA)为交联剂在注射器中制备聚合物整体柱,用其固相萃取尿液中溴西泮(BRZ)、劳拉西泮(LRZ)和地西泮(DZP)3种苯二氮■类药物(BZDs),并采用高效液相色谱法(HPLC)分析。实验考察了整体柱聚合时间及固相萃取条件(淋洗溶液、洗脱溶剂种类和体积)对BZDs萃取效率的影响。结果表明,仅聚合4 h得到的整体柱对BZDs吸附效率为100%。取尿液样品4 mL上样,用4 mL H_2O冲洗,1 mL乙酸乙酯洗脱,采用高效液相色谱分析。在最优条件下,3种BZDs在4.0～1 000 ng/mL范围内线性关系良好(r=0.999),检出限(S/N=3)和定量限(S/N=10)分别为1.0～1.2 ng/mL和3.3～4.0 ng/mL;在10、25和50 ng/mL加标水平下回收率为81.4%～102%,日内(n=3)和日间(n=3)相对标准偏差分别为1.2%～4.5%和2.5%～8.3%。该整体柱可对尿液中3种BZDs有效净化,且富集达12～15倍。方法构筑的聚合物整体柱制备简单,萃取高效,可成功用于尿液中3种BZDs的分析。     

罗丹宁-壳聚糖固相萃取-原子吸收光谱法测定环境水样中痕量银

本文采用化学修饰技术制备了新型固相萃取材料罗丹宁-壳聚糖,用傅立叶红外(IR)光谱对其进行了表征。以该材料作为固相萃取剂,采用火焰原子吸收(FAAS)法为检测手段,在动态条件下系统研究了该吸附材料对痕量Ag+的吸附性能。研究结果表明:在pH=5.0,室温下以1.8mL/min速度流过分离柱,试液中的Ag+能被该材料定量吸附,其动态饱和吸附容量为72.62mg/g。吸附的Ag+可用8mL 0.1mol/L硫脲-0.05 mol/L HNO3混合液以0.7 mL/min流速完全洗脱,洗脱液中的Ag+用FAAS法测定。该方法对Ag+的检出限(3σ,n=11)为8.50μg/L,线性范围为0.01~5.0mg/L,相对标准偏差(RSD)为0.72%;加标回收率在97.8%~102.7%之间。方法用于实际环境水样中痕量Ag+的测定,结果满意。     

固相萃取-衍生化-气相色谱-质谱联用法同时测定尿液中4种阿片类物质

公安机关用胶体金尿检法对海洛因滥用者的检测常常受到阿片类镇咳药的干扰,使用传统液-液提取法进行实验室检验,操作效率低,灵敏度不高,无法满足公安机关打击涉毒案件的需要。为此,该研究建立了尿液中吗啡、O ⁶ -单乙酰吗啡、可待因和乙酰可待因4种阿片类物质的固相萃取和衍生化技术结合气相色谱-质谱联用（GC-MS）同时检测方法。尿样用磷酸盐缓冲液调节至pH=6后,经MCX固相萃取柱净化,用N -甲基-N -（三甲基硅烷基）三氟乙酰胺（MSTFA）对吗啡、O ⁶ -单乙酰吗啡、可待因进行衍生化,供GC-MS检测。考察了上样和洗脱流速、淋洗液中甲酸体积分数、洗脱液中氨水体积分数、3%（v/v）甲酸甲醇淋洗液体积和固相萃取柱吹干时间对萃取效果的影响。确定上样和洗脱流速1.0 mL/min,淋洗液中甲酸体积分数3%,洗脱液中氨水体积分数5%,3%（v/v）甲酸甲醇淋洗液体积1 mL,吹干时间1 min为最佳条件。在此条件下,4种阿片类物质在0.02~0.8 μg/mL范围内线性关系良好（r ² ≥0.998）,检出限（LOD）为0.0016~0.0039 μg/mL,定量限（LOQ）为0.0054~0.0128 μg/mL,当标准添加水平为0.02、0.1、0.2 μg/mL时,回收率为93.0%~110.3%。该方法结合自动化技术,对固相萃取条件精确控制,操作简便、快速、灵敏、准确,适合尿液中吗啡等4种阿片类物质快速测定,可用于海洛因吸食者的大规模监控,并能准确排除因服用含阿片类镇咳药导致的吗啡胶体金尿检假阳性。     

竹炭固相萃取-高效液相色谱法测定河水中多环芳烃

建立了竹炭固相萃取-反相高效液相色谱法检测水中16种多环芳烃的方法。通过实验综合分析,选定正己烷为洗脱溶剂,洗脱溶剂体积为15mL,上样速率为5mL/min,上样体积为750mL。此萃取条件下的萃取回收率在50.3%～143.2%之间。经萃取后,方法的最低检出限范围为0.011～0.069μg/L,精密度在3.3%～11%之间。用该法测定河水中多环芳烃的含量,水样的加标回收率在50.3%～138.4%范围内。     

基于咪唑酯骨架结构材料-7的涡旋辅助微固相萃取

采用漩涡辅助微固相萃取的样品前处理方法,并结合高效液相色谱检测水样中的紫外吸收剂。沸石咪唑酯骨架结构材料-7(ZIF-7)具有大的比表面积,永久性孔道,开放的金属位点,以及较高的化学稳定性及水热稳定性,本文将ZIF-7作为固相萃取剂用于微固相萃取水样中的紫外吸收剂。实验考察了萃取剂用量、萃取时间、洗脱溶剂、洗脱时间、溶液pH值和盐浓度等对萃取效率的影响。最优实验条件为:ZIF-7的质量为15 mg,萃取时间是8 min,洗脱剂是甲醇∶乙腈(体积比3∶7),洗脱时间为5 min, NaCl溶液浓度为0 mg/mL,溶液pH为3。在此条件下,方法在2.5～750 ng/mL的范围内具有良好的线性,检出限为0.2～0.8 ng/mL,定量限为1.0～2.5 mg/mL。采用该方法分析实际水样中的紫外吸收剂,加标回收率为90.3%～111.5%,相对标准偏差为1.4%～7.2%,结果良好。     

固相萃取-高效液相色谱法测定人体尿液中邻苯二甲酸酯及其代谢物

建立了同时测定人体尿液中邻苯二甲酸酯及其代谢物的分析方法.对洗脱剂种类、洗脱体积、洗脱流速等影响因素进行考察,确定了最佳洗脱剂及洗脱体积为2mL乙腈、2mL乙酸乙酯和1mL乙醚-正己烷(1:19,V/V),洗脱流速1mL/min.在最优化的固相萃取-液相色谱条件下测定5种邻苯二甲酸酯及其5种相应的单酯代谢物,线性范围为...     

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.