金标记羟胺放大化学发光检测赭曲霉毒素A

以羧基磁性微球为分离载体,连接氨基捕获探针和适配体,加入生物素化报告序列和赭曲霉毒素A(Ochratoxin A,OTA)竞争结合适体,继续加入链霉亲和素纳米金和羟胺/Au~(3+)以显著提高化学发光检测OTA的灵敏度,从而建立了一种纳米金标记羟胺放大化学发光检测OTA的高灵敏度方法。优化了羧基磁性微球、氨基捕获探针、适配体、生物素化报告序列、链霉亲和素纳米金的用量。优化条件下,在OTA质量浓度0.01~50 ng/m L范围内,化学发光信号值与OTA浓度的对数呈较好的线性关系(r~2=0.992 5),检出限为1.58×10~(-3)ng/mL。对啤酒样品进行OTA加标回收实验,回收率为97.4%~105.4%,相对标准偏差为4.0%~5.5%。     

赭曲霉毒素A模拟抗原表位及噬菌体展示酶联免疫吸附分析法的建立

以驴抗鼠二抗包被微孔板,以捕获方式包被抗赭曲霉毒素A(OTA)单克隆抗体,利用噬菌体随机七肽库筛选OTA模拟抗原表位,并以其替代检测抗原,建立了基于噬菌体展示技术的酶联免疫吸附分析(Phage ELISA)检测OTA的方法.结果表明,筛选获得的模拟OTA抗原表位七肽氨基酸序列为GMSWMMA.基于模拟表位噬菌体建立的Phage ELISA方法半数抑制浓度(IC50值)为(0.15±0.02) ng/mL,检测OTA的线性范围为0.03～ 0.50 ng/mL,OTA的检出限为0.03 ng/mL,且Phage ELISA与其它4种常见真菌毒素(黄曲霉毒素B1、伏马毒素B1、脱氧雪腐镰刀菌烯醇及玉米赤霉烯酮)无交叉反应.大米样品OTA加标实验表明,批内加标回收率为97.0％ ～ 115.2％,批间加标回收率为107.2％ ～ 123.1％,与ELISA试剂盒检测结果比较,无显著性差异.     

基于上转换荧光纳米粒子和金纳米粒子间荧光共振能量转移的高灵敏赭曲霉毒素A检测方法研究

制备了水溶性的上转换荧光纳米材料,在其表面修饰赭曲霉毒素A(OTA)适配体作为能量供体探针;在金纳米粒子表面修饰OTA适配体互补链作为能量受体探针,构建了OTA适配体传感器。在最优条件下,OTA的检测范围为0.001~10 ng/mL,检出限可达0.001 ng/mL。将其应用于啤酒样品中OTA的检测,当加标水平为0.01、0.1、1.0 ng/mL时,回收率为100%~119%,相对标准偏差为4.3%~4.9%,表明该方法可用于实际样品检测。该方法具有灵敏度高、特异性好、操作简单、成本较低等优点。     

化学发光酶免疫分析测定鱼肉中呋喃它酮代谢物方法研究

建立了呋喃它酮代谢物5-吗啉甲基-3-氨基-2-6唑烷基酮(AMOZ)间接竞争化学发光酶免疫分析(icCLEIA)检测方法,通过单因素实验优化了包被原浓度、抗体稀释倍数、反应缓冲体系及浓度、竞争反应时间等参数,结果表明icCLEIA最佳反应条件为:包被抗原浓度为10 ng/mL,抗体稀释60000倍,最佳竞争时间为50 min,体系缓冲液0.01 mol/L PBS(pH 7.4).在优化的条件下,本方法的线性检测范围为0.026 ～3.52 μg/L,IC50为0.29 μg/L,检出限(LOD,IC10)为0.012 μg/L.对鱼肉样品的平均添加回收率在101.4％～115.5％之间.建立的icCLEIA方法可用于实际样品中AMOZ残留检测.     

超高效液相色谱-串联质谱法测定犬血浆中利培酮和帕潘立酮及药代动力学研究

建立了超高效液相色谱-串联质谱法(UPLC-MS/MS)测定犬血浆中利培酮和帕潘立酮的浓度.血浆样品用乙腈沉淀蛋白后,用Zorbax SB-C18柱分离,以乙腈-10 mmol/L乙酸铵溶液(65∶35,V/V)为流动相,在电喷雾离子源正离子模式下以多反应监测(MRM)方式进行检测.利培酮、帕潘立酮分别在0.05～30.0 ng/mL和0.10～30.0 ng/mL范围内线性关系良好(r2＞0.99),定量限分别为0.05 ng/mL和0.10 ng/mL,回收率分别为91.2％～95.1％和93.1％～97.5％.该方法精密、准确、快速,适用于临床血药浓度的监测及利培酮缓释微球药动学的研究.     

盐析效应结合顶空气相色谱质谱法测定香精香料中甲醇含量

利用盐析效应结合顶空-气相色谱/质谱联用仪,建立了一种快速、准确检测香精香料中甲醇含量的方法.方法以5 mol/L NaCl溶液为顶空基质校正剂,试验得线性范围为0.8~200 ng/mL(r~2=0.999 9,n=6),检出限为0.25ng/mL,定量限为0.84 ng/mL,日内精密度1.8%,日间精密度4.2%,样品加标回收率为96.51%~114.98%.测得随机抽取的10个含有香精香料样品中甲醇的质量浓度在0.0~8.4 ng/mL之间.方法无需前处理,灵敏度高,选择性好,定性准确,适用于香精香料中甲醇含量的测定.     

呋喃它酮代谢物时间分辨荧光免疫分析法的建立与应用

建立了Eu3+标记的间接竞争时间分辨荧光免疫分析法( Indirect competitive time-resolved fluoroimmu-noassay , ic-TRFIA)用于鱼肉样品中呋喃它酮代谢物AMOZ的检测。通过单因素实验考察了包被抗原浓度、抗体稀释倍数、竞争反应时间等参数对方法灵敏度的影响。结果表明,ic-TRFIA的最佳反应条件为：包被抗原浓度为0.25μg/mL,抗体稀释5×104倍,最佳竞争时间为50 min。在优化的条件下,方法的检出限( LOD, IC10)为0.01 ng/mL,半抑制浓度(IC50)为0.26 ng/mL,线性范围(IC20~IC80)为0.025~2.83 ng/mL,对鱼样中AMOZ回收率在78.0%~86.0%之间,各样品变异系数均小于15%,与HPLC-MS/MS对比检测结果显示相关性良好。本方法灵敏度高、特异性好,能够满足实际样品的检测需求。     

超高效液相色谱-串联质谱法同时测定化妆品中50种非法添加药物

建立超高效液相色谱-串联质谱(UPLC-MS/MS)同时测定化妆品中50种非法添加化学药物定性筛查及定量分析方法.不同基质样品经乙腈溶液(含0.5%甲酸)提取后,冷冻离心,上清液采用2 mg/L乙二胺四乙酸二钠水溶液定容,以甲醇-0.1%甲酸溶液为流动相,经CAPCELL CORE C18色谱柱梯度洗脱分离.采用电喷雾电离(ESI),以多重反应监测(MRM)模式进行正负离子检测.所测50种化学药物在10~100 ng/mL范围内呈现良好的线性关系(r值均大于0.991 0),精密度、重复性良好,平均回收率在87.2%~109.7%之间,相对标准偏差(RSD)不超过10.0%,方法检出限为0.05~33 ng/g,定量限为0.15~99 ng/g.方法简便、灵敏度高、重复性好,可以实现化妆品中50种非法添加化学药物快速、准确的定性筛查和定量测定.     

基质分散固相萃取-高效液相色谱/串联质谱法检测红薯中氯吡脲

建立了分散固相萃取-高效液相色谱/串联质谱法测定红薯中氯吡脲含量的分析方法.样品经分散剂(硅胶,C18HC)研磨分散提取,甲醇洗脱.采用Thermo Hypersil Gold C18色谱柱(150×2,1 mm,5μm)分离,以甲醇(A)/0.1％甲酸-5 mmol/L甲酸铵(B)作为流动相,梯度洗脱,采用串联质谱在正离子扫描方式下,通过选择反应模式定量分析,外标法定量.氯吡脲在2.63～675.00 ng/mL范围内线性关系良好,相关系数R2＞0.999.定量检测限为0.66 ng/mL.氯吡脲在10、25、50 ng/g三个浓度水平的添加回收率在70％～130％之间.该方法操作简单、准确,适用于红薯中氯吡脲的定量检测.     

保健食品中西地那非化学发光免疫分析方法研究

针对保健食品中西地那非药物的非法添加问题,该研究采用辣根过氧化物酶（HRP）与鲁米诺为信号输出系统,结合直接竞争模式探索了保健食品中西地那非的直接竞争化学发光酶免疫分析方法。基于特异性多克隆抗体,通过逐步优化策略,确定最佳免疫分析条件为：包被原质量浓度为41.67 ng/mL,酶标抗体质量浓度为1.25 μg/mL,封闭液和洗涤液的吐温－20含量为0.05%,稀释液的甲醇添加量为5%,竞争反应时间为40 min。在该条件下,建立了西地那非的直接竞争化学发光免疫分析方法,该方法对西地那非的半抑制浓度（IC50）为0.17 ng/mL,线性检测范围（IC20～IC80）为0.024 ~ 1.21 ng/mL,检出限（IC10,LOD）为0.008 ng/mL。与他达那非等功能类似物无显著交叉;西地那非样品的加标回收率为82.0%～114%,相对标准偏差均小于15%。盲样检测结果与HPLC－MS/MS确证方法具有良好一致性,说明该方法准确可靠,适用于样品中西地那非的快速筛查。     

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.