基于新型量子点荧光微球的氯霉素免疫层析试纸条的制备和应用

以羧基化CdTe/ZnSe量子点荧光微球为标记物,通过1-乙基-(3-二甲基氨基丙基)碳二亚胺/N-羟基琥珀酰亚胺(EDC/NHS)活化法将氯霉素(CAP)单克隆抗体与量子点荧光微球偶联制备荧光探针.氯霉素全抗原(CAP-HS-BSA)及羊抗鼠二抗分别喷涂硝酸纤维素膜,形成检测线(T线)和质控线(C线),组装成新型氯霉素量子点荧光微球免疫层析试纸条,建立了快速、定量检测牛奶中CAP的方法.本研究开发的量子点荧光微球试纸条可在15 min内完成牛奶样品中CAP的定量检测,线性范围为0.1~100.0μg/L,检出限为0.1μg/L.牛奶样品CAP的加标回收率为93.3%~97.9%,相对标准偏差在4.9%~6.9%之间.     

基于量子点微球免疫层析法快速灵敏检测鸡肉中甲氧苄啶

建立了一种快速灵敏检测甲氧苄啶的量子点微球免疫层析法,对pH、标记抗体浓度、试纸条检测线上的抗原浓度以及试纸条结合垫上的探针体积进行了优化。通过量子点微球试纸条检测仪读取试纸条上检测线和质控线的荧光信号强度,以甲氧苄啶的浓度为横坐标,检测线和质控线荧光信号强度的比值为纵坐标,建立标准曲线。结果表明,方法定量检测范围为1～32μg/L,半抑制率为3.3μg/L,回收率在99.8%～117.4%之间,与12种磺胺类药物均只有不到2%的交叉反应率。该方法适合大批量样品的现场筛查。     

CdTe/ZnSe核壳量子点免疫层析试纸条检测克伦特罗的研究

采用巯基丁二酸作为表面修饰剂,水相法合成水溶性的CdTe/ZnSe核壳量子点,然后在N-羟基琥珀酰亚胺(NHS)的作用下,将CdTe/ZnSe核壳量子点与抗克伦特罗多克隆抗体(Anti-CLE pAb)连接。通过凝胶电泳和斑点杂交实验,验证CdTe/ZnSe核壳量子点与Anti-CLE pAb连接成功,并且CdTe/ZnSe-Anti-CLE pAb偶联物能识别克伦特罗-BSA抗原(CLE-BSA)。光谱分析表明,量子点与抗体连接后荧光增强,荧光峰位从628nm红移至635nm。将合成的CdTe/ZnSe-Anti-CLE pAb偶联物作为指示克伦特罗(CLE)分子的荧光标记物,制备出一种用于检测CLE的免疫层析试纸条,其最低检测量可达1μg/L。与ELISA法的对比实验表明,此试纸条能应用于CLE残留的快速检测。     

量子点荧光微球免疫层析试纸条定量检测恶性疟原虫

以羧基化Cd Te/Zn Se量子点荧光微球为荧光标记物,采用1-乙基-(3-二甲基氨基丙基)碳酰二亚胺(EDC)法偶联抗恶性疟原虫富组氨酸蛋白(Pf)单克隆抗体制备荧光探针;以羊抗恶性疟原虫组氨酸多克隆抗体和驴抗鼠二抗分别喷涂硝酸纤维膜,形成试纸条检测线和质控线,建立了免疫层析试纸条定量检测血清中恶性疟原虫的方法。所使用的羧基化量子点荧光微球的荧光强度为单个量子点的2800倍。实验结果表明,该荧光试纸条定量检测血清中恶性疟原虫线性范围为5.8~8010 Parasite/μL,最低灵敏度达到5.8 Parasite/μL,单个样品检测时间只需15 min。加标回收实验显示,试纸条批内回收率为93.0%~111.8%,批间回收率为98.3%~115.1%,且批内、批间的相对标准偏差均小于5%。     

量子点标记荧光免疫分析测定雌三醇

采用包被雌三醇完全抗原竞争免疫分析模式,以量子点标记羊抗兔抗体为荧光探针,建立了一种测定雌三醇的量子点标记的荧光免疫分析新方法.方法测定雌三醇的线性范围为0.01～10 000μg/L;检出限为0.007 5μg/L.此法用于尿液样品的分析,并利用高效液相色谱法进行对照,测定结果一致。     

基于CdTe量子点测定中性粒细胞明胶酶相关载脂蛋白的免疫荧光层析法

建立了一种基于CdTe量子点标记技术测定中性粒细胞明胶酶相关载脂蛋白(NGAL)的免疫层析法。用水相法制备的CdTe量子点作为荧光探针标记于NGAL的一株单抗,采用双抗体夹心法,制备了检测NGAL的层析试纸条,用于测定NGAL的含量。NGAL的线性范围为41~2 050μg·L-1,检出限为27.35μg·L-1。对NGAL不同浓度的质控品连续测定10次,测定值的相对标准偏差在3.6%~9.7%之间。方法应用于尿液样品的分析,结果与酶联免疫吸附测定法对照,两种方法所得结果间无显著偏差。     

基于上转换发光纳米材料NaYF_4:Yb,Er的免疫层析试纸条测定血清中的降钙素原

制备上转换发光纳米材料(UCP)——NaYF_4:Yb,Er,进行表面功能化修饰后将其作为荧光标记物,制备了快速测定血清中降钙素原(PCT)的免疫层析试纸条。通过优化得到免疫层析反应的最佳条件:抗体标记量为15mg·g~(-1),UCP免疫复合物的用量为40μg,检测线抗体划膜量为1.0μL·cm~(-1),孵育时间为5min。PCT的线性范围为0.05~50μg·L~(-1),检出限(3s/k)为0.020μg·L~(-1)。应用制得的免疫层析试纸条测定血清样品中的PCT,结果与罗氏电化学发光法的结果一致,测定值的相对标准偏差(n=3)小于23%。     

基于荧光硅球的克伦特罗快速定量免疫层析试纸条的研制

采用荧光硅球为标记物制备了快速定量检测克伦特罗(CLE)的荧光硅球免疫层析试纸条。通过正交实验得到最优荧光硅球抗体标记量、硅球垫抗体标记物用量以及检测线抗原浓度。在最优条件下,试纸条线性范围为0.28~3.3 mg/L。猪尿样品CLE加标回收率为81.7%~101%,表明此试纸条可实现猪尿中CLE残留的快速定量检测。     

基于量子点荧光微球的噻虫嗪快速定量免疫层析试纸条的研制

构建了一种基于量子点荧光微球的噻虫嗪快速测定免疫层析试纸条。该试纸条以偶联噻虫嗪单克隆抗体的量子点微球为荧光探针,噻虫嗪完全抗原(TMX-BSA)为T线,山羊抗小鼠IgG为C线。结果表明,抗体在探针合成中的最佳添加量为16μg、缓冲液pH 6.0、 N-(3-二甲氨基丙基)-N’-乙基碳二亚胺盐酸盐(EDC)浓度为0.1 mg/mL。试纸条对噻虫嗪检测在1～200 ng/mL范围内呈线性关系,标准曲线方程为y=-0.42x+0.99 (R²=0.989),检出限为1.64 ng/mL。将构建的试纸条应用于粮食样品中噻虫嗪的检测,加标回收率为79.5%～110.2%,相对标准偏差(RSD)为0.58%～12%,表明其可以满足粮食样品中残留的噻虫嗪检测。     

不同尺寸量子点-菲啰啉体系对镉检测的影响

采用不同尺寸的高荧光量子产率、单分散性水溶性CdTe量子点(QDs)与菲啰啉(Phen)配体结合,组装成QDs-Phen荧光探针。Phen对不同尺寸量子点荧光猝灭效率以及光致空穴转移效率表现为:2.3 nm的绿色CdTe量子点2.8 nm的黄色CdTe量子点3.3 nm的橙色CdTe量子点;不同粒径QDs-Phen荧光探针对Cd~(2+)的检测发现:粒径2.3 nm QDs-Phen荧光探针对Cd~(2+)检测线性范围为0.02~0.6μmol/L,检测限为0.01 mol/L;粒径2.8 nm QDsPhen荧光探针对Cd~(2+)检测线性范围为0.1 nmol/L~1.0μmol/L,检测限为0.05 nmol/L;而粒径3.3 nm QDs-Phen荧光探针对Cd~(2+)检测线性范围为0.2 nmol/L~1.5μmol/L,检测限为0.1 nmol/L。为选择合适粒径量子点的荧光探针对Cd~(2+)实际检测提供依据。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.