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71.
72.
A flow-based enzyme-linked immunosorbent assay (ELISA) on a polydimethylsiloxane (PDMS) microchip has been developed for the rapid determination of immunoglobulin A (IgA). The analytical principle of this integrated method is the same as the conventional sandwich-type ELISA. A primary antibody (anti-IgA) was adsorbed on the surface of a PDMS microchannel, and then an antigen (IgA) and a secondary antibody (anti-IgA HRP labeled) were reacted successively. The resulting antigen-antibody complex, fixed on the surface of the microchannel, was detected using Amplex® Red and a fluorescent imaging system. The calibration curve of the IgA standard solution was linear in the range of 0-50 ng/mL at the flow rate of 10 μL/min. This flow rate corresponds to the reaction time of 4.8 s. Compared to the conventional assay on a 96-well microtiter plate, the present assay on the microchip dramatically shortened the reaction time necessary for the enzyme-substrate reaction from 30 min to 4.8 s, i.e., to 1/375. The amounts of the reagent and sample were also reduced to 1/100 compared to the 96-well microtiter plate. 相似文献
73.
Fully automated liquid chromatography-mass spectrometry determination of 17beta-estradiol in river water 总被引:1,自引:0,他引:1
Watabe Y Kubo T Nishikawa T Fujita T Kaya K Hosoya K 《Journal of chromatography. A》2006,1120(1-2):252-259
Surface modified molecularly imprinted polymers (SM-MIPs) for 17beta-estradiol (E2), utilizing 6-ketoecradiol as a pseudo template were prepared. MIPs for E2 were synthesized using 4-vinyl pyridine and ethylene dimethacrylate as a functional monomer and cross-linking agent, respectively. MIPs selectively retained E2 and provided excellent chromatographic resolution from interfering compounds inherent in river water sample matrices. Therefore, freshly prepared MIPs were applied to quantitative mass spectrometric (negative electrospray ionization mode) detection of low levels of E2 in river water sample. In order to pre-concentrate the target compound for HPLC analysis, column switching was coupled with a pretreatment column packed with the MIPs. The repeatability of actual determinations of river water sample, in which background E2 was not detected, spiked with 50 ng/L of E2 was 2.2% RSD with a detection limit and qualification limit of 1.8 and 5.4 ng/L, respectively. Surface modification of MIP particlefs packed in the pretreatment column provided selective affinity and on-line concentration of low levels of E2 while simultaneously eliminating sample matrix interference, resulting in a significant increase in sensitivity and reproducibility for liquid chromatography-mass spectrometry analysis of E2 in river water sample. 相似文献
74.
Hayami S Hashiguchi K Juhász G Ohba M Okawa H Maeda Y Kato K Osaka K Takata M Inoue K 《Inorganic chemistry》2004,43(14):4124-4126
Cobalt(II) compounds [Co(pyterpy)Cl(2)].MeOH (1.(MeOH)) and [Co(pyterpy)Cl(2)].2H(2)O (1.(2H(2)O)) were synthesized. The compound 1.(MeOH) forms the quasi 3-D networks by making pi-pi stacking between the 1-D chains. The methanol molecules from 1.(MeOH) can be removed by heating, and substituted by absorption of water molecules. The MeOH molecules in 1.(MeOH) are removed by heating at 410 K, and they are substituted by water molecules to form 1.(2H(2)O). 1.(2H(2)O) exhibits a S = (3)/(2) (HS) left arrow over right arrow S = (1)/(2) (LS) spin transition with a thermal hysteresis. We have succeeded in constructing a guest dependent 1-D spin-crossover cobalt(II) compound. 相似文献
75.
Mitsuru Suda Takuya Hagihara Noriyoshi Suya Tsuyoshi Hamano Masashi Takada Teruaki Konishi Takeshi Maeda Yasushi Ohmachi Shizuko Kakinuma Kentaro Ariyoshi Yoshiya Shimada Hitoshi Imaseki 《Radiation Physics and Chemistry》2009,78(12):1216-1219
We developed a neutron irradiation facility, neutron exposure accelerator system for biological effect experiments (NASBEE) for biological studies in National Institute of Radiological Sciences, Japan. Irradiation field of 2 MeV average neutrons generated by a Be(d–n)B reaction is established. Dose uniformity of 240 mm in diameter irradiation field is producible within ±2.5% with a dose rate of 0.87 Gy/h at sample target distance of 1170 mm. Two irradiation rooms, a specific pathogen-free (SPF) conditioned one and a conventional, are now available. Irradiation protocols for in vitro experiments are now established and demonstrated by obtaining a relative biological effectiveness (RBE) of cell inactivation measured to be 3.54 with 10% survival dose (D10). 相似文献
76.
Characterization of the compound Ti(C(5)H(5))(2)Cl(2) was studied using Li(+) ion attachment mass spectrometry (IAMS) as an analytical methodology. Since this target compound is used as an anticancer drug in the treatment of leukemia, accurate and rapid monitoring methods for the determination of titanium drugs in a hospital environment are desirable. A quadrupole mass spectrometry system along with a Li(+) ion attachment technique and a direct inlet probe (DIP) produced the Li(+) adduct of Ti(C(5)H(5))(2)Cl(2), Ti(C(5)H(5))(2)Cl(2)Li(+). The DIP also was used to study the temperature-resolved behavior of this compound. The slope of the plot of signal intensity of Ti(C(5)H(5))(2)Cl(2)Li(+) versus temperature for Ti(C(5)H(5))(2)Cl(2) sublimation from 60 to 100 °C was used to determine an apparent activation energy (E(a)) of 124.43 kJ/mol for the sublimation of Ti(C(5)H(5))(2)Cl(2). This value is comparable to the reported value of 118.8 kJ/mol for molar enthalpy of sublimation of Ti(C(5)H(5))(2)Cl(2). These results demonstrate that the IAMS methodology can be used to study the enthalpy of sublimation for d-metal complex materials. 相似文献
77.
Tomoyuki Manaka Shin‐Ichiro Nagayama Wannaporn Desadee Naoki Yajima Takuya Kumamoto Toshiko Watanabe Tsutomu Ishikawa Masatoshi Kawahata Kentaro Yamaguchi 《Helvetica chimica acta》2007,90(1):128-142
Nucleophilic ring‐opening reactions of 3‐aryl‐1‐benzylaziridine‐2‐carboxylates were examined by using O‐nucleophiles and aromatic C‐nucleophiles. The stereospecificity was found to depend on substrates and conditions used. Configuration inversion at C(3) was observed with O‐nucleophiles as a major reaction path in the ring‐opening reactions of aziridines carrying an electron‐poor aromatic moiety, whereas mixtures containing preferentially the syn‐diastereoisomer were generally obtained when electron‐rich aziridines were used (Tables 1–3). In the reactions of electron‐rich aziridines with C‐nucleophiles, SN2 reactions yielding anti‐type products were observed (Table 4). Reductive ring‐opening reaction by catalytic hydrogenation of (+)‐trans‐(2S,3R)‐3‐(1,3‐benzodioxol‐5‐yl)aziridine‐2‐carboxylate (+)‐trans‐ 3c afforded the corresponding α‐amino acid derivative, which was smoothly transformed into (+)‐tert‐butyl [(1R)‐2‐(1,3‐benzodioxol‐5‐yl)‐1‐methylethyl]carbamate((+)‐ 14 ) with high retention of optical purity (Scheme 6). 相似文献
78.
79.
The rotational spectrum of the NiS radical in the X(3)Sigma(-) state was observed by employing a source-modulation microwave spectrometer. The NiS radical was generated in a free space cell by a dc glow discharge in H(2)S diluted with Ar. The nickel atoms were supplied by the sputtering reaction from a nickel cathode. Rotational transitions with J = 11-10 to 25-24 were measured in the region between 135 and 314 GHz. Rotational, centrifugal distortion and several fine-structure constants were determined by a least-squares analysis. Other spectroscopic parameters such as dissociation energy, vibrational wavenumber and equilibrium bond length were also derived from the determined molecular constants. Excitation energies of the lowest (3)Pi and (1)Sigma(+) states were estimated from the fine-structure constants, lambda and gamma. 相似文献
80.
The reaction of allyltitanocenes with five- to seven-membered cyclic enones proceeded with good to high diastereoselectivity depending on the ring size of enones. The stereochemistry of the major isomers produced by the reaction of cinnamyltitanocene was opposite to that of crotyltitanocene. 相似文献