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71.
Jia-Ming Liu Xiao-Mei Huang Zhen-Bo Liu Fei-Ming Li Zhi-Ming Li Lian-Ying Li 《Analytica chimica acta》2009,648(2):226-182
A new phosphorescent labelling reagent consisting of fullerol, fluorescein isothiocyanate and N,N-dimethylaniline (F-ol-(FITC)n-DMA) was developed. The mode of action is based on the reactivity of the active -OH group in F-ol with the -COOH group of FITC to form an F-ol-(FITC)n-DMA complex containing several FITC molecules. F-ol-(FITC)n-DMA increased the number of luminescent molecules in the biological target of WGA-AP-WGA-F-ol-(FITC)n-DMA (WGA and AP are wheat germ agglutinin and alkaline phosphatase, respectively) which improved the sensitivity using solid substrate room temperature phosphorimetry (SSRTP) detection. The proposed method provided high sensitivity and strong specificity for WGA-AP. The limit of detection (LD) was 0.15 ag AP spot−1 for F-ol and 0.097 ag AP spot−1 for FITC in F-ol-(FITC)n-DMA, which was lower than the method using single luminescent molecules of F-ol-DMA and FITC-DMA to label WGA (0.20 ag AP spot−1 for F-ol-DMA and 0.22 ag AP spot−1 for FITC-DMA). Results for the determination of AP in human serum were in good agreement with those obtained by enzyme-linked immunosorbent assay. The mechanism of F-ol-(FITC)n-DMA labelling of WGA was discussed. 相似文献
72.
This paper involves the preparation of thioureas, which couple with per‐O‐acetylated galactosyl isothiocyanate 1 and 2‐aminobenzothiazole 2 to give incorporating galactosylthiourea derivatives 3. Nucleophilic addition of active primary amine to 3 in the presence of HgCl2 afforded the per‐O‐acetylated guanidinogalactoside 4a‐4d, 5a‐5d, 6a‐6d, 7a‐7d in good yield. These adducts were subjected to deacetylation in MeOH/NaOMe and furnished the corresponding unprotected guanidinogalactosides 8a‐8d, 9a‐9d, 10a‐10d, 11a‐11d. The structures of all newly synthesized compounds were established by IR, 1H NMR, MS and elemental analysis. 相似文献
73.
A new ultraviolet (UV) labeling reagent, p-acetamidobenzenesulfonyl fluoride (PAABS-F), was designed and synthesized to label and determine the amino acids by capillary electrophoresis (CE) with diode-array detector (DAD). PAABS-F is very stable and easy to synthesize. It reacted with primary or secondary amino acids very quickly under facile conditions to give corresponding derivatives in high yield with excellent sensitivity and stability. No by-products were observed in amino acid derivatives when stored at room temperature under natural daylight for at least 7 days. Both amino acids standard solution and real samples reacted with this new UV labeling reagent smoothly to form high UV-absorption derivatives. The labeled 20 standard amino acids were efficiently separated by CE and the mass detection limits (S/N = 3) were ranged from 59.3 fmol for l-tryptophan to 1.70 pmol for l-histidine. 相似文献
74.
基于异硫氰酸荧光素(FITC)可发射强而稳定的荧光信号,KIO3能氧化FITC而发生荧光猝灭,Se(Ⅳ)使FITC的荧光强烈猝灭,Se(Ⅳ)的含量与ΔF值呈线性关系,建立催化KIO3氧化FITC荧光猝灭法测定痕量硒的新方法.方法的线性范围为0.012~2.000×10-15g Se(Ⅳ)/mL,工作曲线回归方程ΔF=1.18+72.74CSe(Ⅳ)(×10-15g/mL)(n=6,r=0.9997),检出限为2.1×10-18g/mL(n=11).分别对Se(Ⅳ)浓度0.012和2.000×10-15g/mL进行7次测定,RSD依次为2.8%和3.5%.用于实际样品中痕量硒的测定和人体疾病的诊断与预报,结果满意.同时探讨了催化荧光猝灭法测定痕量硒的反应机理. 相似文献
75.
76.
制备了Pr、Yb两种希土元素异硫氰酸盐与苄胺的固体配合物.并对其进行了组成分析、红外光谱分析、X射线衍射物相分析和热重分析.测量了298.15K时两种固体配合物RE(NCS)3·4C6H5CH2NH2在HCl水溶液中的反应热和相应的两种希土元素异硫氰酸盐水合物RE(NCS)3·n1H2O(RE为Pr时,n1=7;RE为Yb时,n1=6)在C6H5CH2NH2-HCl-H2O溶液中的积分溶解热以及苄胺C6H5CH2NH2在HCl水溶液中的反应热.藉助本文所设计的热化学循环,求得了这两种配合物的标准生成焓,还计算了它们的晶格能. 相似文献
77.
E. A. Ukraintseva Yu. A. Dyadin N. V. Kislykh V. A. Logvinenko D. V. Soldatov 《Journal of inclusion phenomena and macrocyclic chemistry》1995,23(1):23-33
Strain measurement and quasiequilibrium thermogravimetry were used to study the dissociation processes of two clathrates, [Ni(MePy)4(NCS)2]·(MePy) and [Cu(MePy)4(NCS)2]·2/3(MePy), accompanied by the liberation of MePy into the gaseous phase. In the Ni clathrate dissociation process in the temperature range 298–368 K the liberated MePy was redistributed between the solid clathrate and gaseous phases; the MePy vapour pressure over the clathrate is a function of temperature and the guest contenty, which agrees with the presence in the MePy-[Ni(MePy)4(NCS)2] system of a wide range of -clathrate solutions, [Ni(MePy)4(NCS)2]·y(MePy). The same methods used to study the Cu clathrate dissociation resulted in conclusions different from those obtained for the dissociation process of the above clathrate: the process is described by the equation [Cu(MePy)4(NCS)2]·2/3(MePy)solid =[Cu(MePy)2(NCS)2]solid+22/3(MePy)gas; the temperature dependence of the Mepy vapour pressure over the solid sample does not depend on its composition, which points to the absence from the system of solid solutions based on the clathrate. Standard changes of the enthalpy, entropy, and isobaric-isothermal reaction potential for the temperature range 292–325 K are equal to 178.6±1.7 kJ (mole of clathrate)–1, 463±5.6 J (mole of clathrate)–1 K–1, and 40.4±2.4 kJ (mole of clathrate)–1, respectively. 相似文献
78.
《Surface and interface analysis : SIA》2006,38(3):173-177
Structures of self‐assembled monolayers (SAMs) prepared from benzyl isothiocyanate (BZIT) and phenyl isothiocyanate (PHIT) were comparatively investigated by means of surface enhanced Raman scattering (SERS) on gold nanoparticle surfaces. Both the molecules are assumed to have upright geometries binding via the sulfur atom, from the SERS spectral features. The broad and split bands at ~2100 cm?1 could be ascribed to the combination band ν9a + ν12 of the phenyl ring vibrations through a Fermi‐resonance interaction with the ν3(NCS) band in the neat‐liquid state. Such broad bands became quite symmetric upon adsorption on Au. UV‐vis absorbance spectroscopy and cyclic voltammetry (CV) were used to compare the kinetics of the formation of SAMs on gold. Our results suggest that BZIT should have a relatively faster self‐assembly than PHIT, as indicated from signal decrease in the CV graph, which suggests a more vertical stance for BZIT in line with Raman measurements. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
79.
Phenethyl isothiocyanate isolated from Armoracia rusticana root oil and its derivatives were tested at different doses in a bioassay designed to evaluate repellency against individual Haemaphysalis longicornis nymphs. Among the tested compounds, benzyl isothiocyanate exhibited repellency against H. longicornis nymphs at the lowest dose of 0.00625 mg/cm2, followed by phenethyl isothiocyanate (0.0125 mg/cm2) and phenyl isothiocyanate (0.025 mg/cm2). The behavioral responses of H. longicornis nymphs exposed to benzyl isothiocyanate and phenethyl isothiocyanate indicated that the mode of action of these compounds can be mainly attributed to the vapor phase. Encapsulated benzyl isothiocyanate showed repellency up to 120 min post-application at 0.1 mg/cm2, whereas pure benzyl isothiocyanate showed repellency up to 60 min post-application at 0.1 mg/cm2. The present study suggests that benzyl isothiocyanate is a potential repellent for protection against H. longicornis nymphs, and encapsulation in yeast cells may enhance the repellency effect. 相似文献
80.
Review on recent and advanced applications of monoliths and related porous polymer gels in micro-fluidic devices 总被引:1,自引:0,他引:1
Mercedes Vázquez 《Analytica chimica acta》2010,668(2):100-8248
This review critically summarises recent novel and advanced achievements in the application of monolithic materials and related porous polymer gels in micro-fluidic devices appearing within the literature over the period of the last 5 years (2005-2010). The range of monolithic materials has developed rapidly over the past decade, with a diverse and highly versatile class of materials now available, with each exhibiting distinct porosities, pore sizes, and a wide variety of surface functionalities. A major advantage of these materials is their ease of preparation in micro-fluidic channels by in situ polymerisation, leading to monolithic materials being increasingly utilised for a larger variety of purposes in micro-fluidic platforms. Applications of porous polymer monoliths, silica-based monoliths and related homogeneous porous polymer gels in the preparation of separation columns, ion-permeable membranes, preconcentrators, extractors, electrospray emitters, micro-valves, electrokinetic pumps, micro-reactors and micro-mixers in micro-fluidic devices are discussed herein. Procedures used in the preparation of monolithic materials in micro-channels, as well as some practical aspects of the micro-fluidic chip fabrication are addressed. Recent analytical/bioanalytical and catalytic applications of the final micro-fluidic devices incorporating monolithic materials are also reviewed. 相似文献