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。     

孔雀石绿的磁性免疫层析快速检测方法研究

开发了一种适用于现场快速检测孔雀石绿(MG)的免疫层析试纸条,在超顺磁性纳米微球上偶联MG单克隆抗体作为检测探针,分别将孔雀石绿完全抗原(MG-BSA)和羊抗鼠IgG喷涂于NC膜的T线和C线。结果发现,T线最佳喷涂量为0.25 mg/mL,抗体最佳偶联量为20μg,构建的试纸条可在25 min内实现养殖用水及鱼肉组织的定性与定量分析,检出限为1μg/mL,定量限分别为0.60,0.97 ng/mL,对无色孔雀石绿无交叉反应,批内、批间相对标准偏差均<12%;通过与HPLC和市售胶体金试剂盒对比发现,水样的回收率在82.0%~117.4%,灵敏度高于市售胶体金试剂盒。该孔雀石绿磁性免疫层析条适用于现场快速检测鱼肉或水体中的残留孔雀石绿。     

氟苯尼考胶体金免疫层析定量检测方法的建立

建立了定量检测氟苯尼考的胶体金免疫层析方法.对胶体金标记抗体时溶液pH和抗体浓度、金标抗体用量、检测线上抗原浓度以及检测时间进行了优化.采用胶体金试纸条读取仪测定试纸条检测线和质控线的信号强度,以标准品的浓度为横坐标,阳性样本和阴性样本的检测线/质控线的信号比值(Bx/B0)为纵坐标建立标准曲线.结果表明,胶体金免疫层析试纸定量检测氟苯尼考的线性范围为0.1~1.5 ng/mL,检出限为0.08 ng/mL,检测时间为15 min.本方法具有简便、快速和可定量等特点,适于大批量样品的现场筛查.     

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%。     

人工雌激素己烯雌酚酶联免疫分析方法的建立

本实验旨在初步建立人工合成雌激素己烯雌酚（DES）的酶联免疫吸附分析（icELISA）方法。实验首先合成了己烯雌酚的两种半抗原正丁酸己烯雌酚单醚（DES-CP）、乙酸己烯雌酚单醚（DES-CME）。DES-CP与牛血清蛋白（BSA）偶联作为免疫原免疫BALB/c雌性小鼠并进一步制备了DES单克隆抗体，表征了单克隆抗体的亲和力和特异性。在ELISA优化的条件下，方法的抑制中浓度为 IC₅₀＝9.8 ng/mL，检测限 IC₂₀＝2.3 ng/mL，工作浓度范围为 2-42 ng/mL. 抗体与己烷雌酚、双烯雌酚的交叉反应分别为 44%, 27%，与天然雌激素雌二醇的交叉反应小于0.1%. 评估了分析缓冲液中盐离子浓度、pH、有机溶剂含量等因素对分析方法的影响。本分析方法应用于水样的添加实验，回收率符合分析精度要求。HPLC法对实验结果进行了确证，证明了ELISA应用于水样分析的可靠性。     

基于图像识别原理的金标试纸检测仪样机研制

采用一种互补金属氧化物半导体(简称CMOS)数字图像传感器(TSL1301),研制出了盐酸克伦特罗胶体金标试纸检测仪。在4种不同检测频率(5,30,50和70KHz)条件下,该检测仪线阵图像传感器TSL1301,对空白试纸条检测数据的变异系数均小于0.22%;盐酸克伦特罗浓度为1.0~4.0 ng/m L时,其加标液含量与试纸条T线显色度,具有良好的二次拟合特性(R~2=0.995)。该方法适用于现场对盐酸克伦特罗进行快速定量检测。     

背景荧光猝灭-免疫层析法检测C-反应蛋白

采用背景荧光猝灭-免疫层析法(b FQICA),基于双抗体夹心法原理,将合适浓度的捕获抗体、示踪抗体分别固定在试纸条和微孔内,层析时与样本形成抗体-抗原-抗体的夹心结构,建立了一种操作简便、灵敏度高、抗干扰性强且能快速定量检测C-反应蛋白(CRP)的方法.结果表明,CRP在0.0~100.0 ng/m L浓度范围内与相对荧光强度值(F1/F2)呈现良好的相关性,最低检出限为0.0939 ng/m L,加标回收率为87.69%~111.0%,检测3批试剂的批间和批内相对标准偏差均小于15%,与降钙素原(PCT,20.0 ng/m L)及人血清淀粉样蛋白A(SAA,10.0μg/m L)均无交叉反应.采用该方法与免疫透射比浊法同时测定41例临床血清样本,检测结果相关性良好(r=0.9585,P0.01),2种方法无显著性差异(P0.05).     

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.     

超声提取辅助顶空式固相微萃取/气相色谱-质谱法测定塑胶跑道面层中7种挥发性硫化物

建立了一种检测塑胶跑道面层中二甲基硫(DMS)、二硫化碳(CS2)、甲基乙基硫(MES)、二乙基硫(DES)、二甲基二硫(DMDS)、二乙基二硫(DEDS)、二甲基三硫(DMTS)7种挥发性硫化物(VSCs)的超声提取辅助顶空式固相微萃取/气相色谱-质谱(HS-SPME/GC-MS)分析方法.实验优化了顶空固相微萃取的萃取条件、超声提取条件及气相色谱-质谱参数.在优化条件下,DES、DMDS的线性范围为5～500 ng/g,其余5种VSCs的线性范围为10～500 ng/g,相关系数(r)为0.9847～0.9989,方法的检出限(S/N=3)为0.4～1.4 ng/g,定量下限(S/N=10)为1.3～4.7 ng/g.在低、中、高3个加标水平下的平均回收率为89.6％～104％,相对标准偏差(RSD,n=6)为3.5％～12％.该方法可实现分离、富集和进样一体化,适用于塑胶跑道面层中VSCs含量的日常检测.     

基于适配体胶体金侧向层析试纸快速检测卡那霉素的方法研究

该文基于适配体以及非巯基化核酸修饰的胶体金纳米探针（AuNPs@polyA－DNA）,建立了一种新型的卡那霉素胶体金侧向层析试纸条。分析了试纸条各组装元件,包括适配体浓度、链霉亲和素（SA）与Biotin－DNAT的比例、SA－生物素（Biotin）－DNAT偶联物浓度以及孵育时间与温度等,对显色反应的影响。最佳实验条件为：缓冲液为4xSSC（0.5% Tween 20）,SA与Biotin－DNAT的最佳摩尔比为1∶6,检测区喷涂偶联物SA－Biotin－DNAT浓度为4 μmol/L,适配体浓度为10 nmol/L,室温孵育时间为20 min。在优化条件下,该试纸条对卡那霉素的肉眼分辨浓度为25 ng/mL,线性范围为5.0～125 ng/mL,检出限为1.5 ng/mL。用于蜂蜜中卡那霉素的检测,其回收率为95.1%～105%,相对标准偏差（RSD）为3.4%～8.5%。该试纸条具有灵敏度高、特异性好、架构简单、重复性高等优点,可用于实际样品中卡那霉素的检测。     

A carbanion induced synthesis of highly congested pyrazole and imidazole containing heterocycles

An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.     

Selective synthesis of 4,5-dihydroimidazo- and imidazo[1,5-a]quinoxalines via modified Pictet–Spengler reaction

An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction.     

Understanding the Diels-Alder reactivity of 1,2-azaborine analogues

The Diels-Alder reactivity of 1,2-heteroborines (H₄C₄B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.     

Synthesis of N-substituted carbazolones from α-iodo enaminones via Pd(0)-catalyzed intramolecular coupling under microwave irradiation

A variety of N-aryl and N-alkyl carbazolones were conveniently achieved in good to high yields via Pd₂(dba)₃-mediated intramolecular coupling of N-substituted α-iodo enaminones under microwave irradiation. The Pd(0)-catalyzed cyclization was found to proceed favorably with the more electron-deficient phenyl ring during the reactions involving unsymmetrical N,N-diaryl α-iodo enaminones. This unique property enables the construction of carbazolone skeleton containing nitro substituted benzenoid ring.     

Synthesis of substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles by intramolecular nitrilimine cycloaddition

Both substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles have been synthesized by the 3+2 intramolecular dipolar cycloaddition of nitrilimines to alkynes. This cyclization has been extended to more versatile 3-bromo derivatives by the use of alkynylbromides as dipolarophiles.     

Catalyst free,visible-light promoted photoaddition reactions between C60 and N-trimethylsilylmethyl-substituted tertiary amines for synthesis of aminomethyl-1,2-dihydrofullerenes

An efficient and benign method for the preparation of aminomethyl-substituted fullerenes has been developed. The process, involving catalyst free, visible-light irradiation of 10% EtOH-toluene solutions containing fullerene C₆₀ and N-trimethylsilylmethyl-substituted amines by using a 20 W compact fluorescent lamp, leads to formation of aminomethyl-substituted fullerene adducts in a highly efficient manner. The photoaddition reaction takes place via a pathway initiated by visible light absorption by C₆₀, followed by SET from the amine to the triplet excited state of C₆₀. Ethanol-promoted desilylation of the resulting a minimum radical then generates the corresponding α-amino radical which couples with the C₆₀ radical anion to form the anion precursor of the fullerene adducts. The new approach using visible-light takes place under mild conditions and it does not require the use of photocatalysts. Thus, the method developed in this effort could broadens the range of functionalized fullerene derivatives that can be readily prepared.     

Highly efficient and stereoselective cycloaddition of nitrones to indolyl- and pyrrolylacrylates

The reactions of various nitrones with indolyl- and pyrrolylacrylates proceeds regioselectively with high diastereoselectivity in the case of aldonitrones, and represents an effective method for obtaining new indolyl- and pyrrolyl-substituted isoxazolidine carboxylates stabilized by weak (CH?O) and moderate (NH?N) strength intramolecular hydrogen bonding. The resulting cycloadducts exhibit promising in vitro anti-influenza activities.     

Transition metal-free direct amination of benzoxazoles using formamides as nitrogen sources

A transition metal-free method for the direct amination of benzoxazoles using formamides as nitrogen sources is reported, which was mediated by an inexpensive and environmentally friendly tetrabutylammonium iodide/tert-butyl hydroperoxide system and gave the 2-aminobenzoxazole derivatives with moderate to good yields.     

l-Proline-catalyzed five-component domino reaction leading to multifunctionalized 1,2,3,4-tetrahydropyridines

Multifunctionalized 1,2,3,4-tetrahydropyridines are concisely synthesized in good yields via l-proline-catalyzed or l-proline/FeCl₃-cocatalyzed one-pot multicomponent reactions (MCRs). The MCRs involve a domino hydroamination/prins reaction/Mannich-type reaction/intramolecular dehydration-cyclization process. The molecular structure of 5baa, one of multifunctionalized 1,2,3,4-tetrahydropyridines, was confirmed by single-crystal X-ray diffraction.     

Exploring the scope of the Gewald reaction: Expansion to a four-component process

An efficient four-component reaction was developed to take advantage of the reactivity of the 2-aminothiophene-3-carbonitrile functionality, which is obtained during the classical three-component Gewald reaction. Various α-methylene bearing ketones were reacted with malononitrile, elemental sulfur, and aryl/heteroarylnitrile derivatives in t-BuOH/NaOH to afford 2-arylthieno[2,3-d]pyrimidin-4-amines in high yields. Preliminary studies revealed the photophysical properties of the products and their potential for use as metal sensors.