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911.
A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method using a high-resolution octadecyl silica column compatible with aqueous compounds was developed for the simultaneous determination of benzodiazepines and their metabolites in human serum. This method enabled us to determine multiple benzodiazepines, including flurazepam, bromazepam, chlordiazepoxide, nitrazepam, clonazepam, flunitrazepam, estazolam, clobazam, lorazepam, alprazolam, triazolam, brotizolam, fludiazepam, diazepam, quazepam, prazepam and their metabolites such as 7-aminonitrazepam, 7-aminoclonazepam, 7-acetamidonitrazepam, N-desmethylclobazam and N-desmethyldiazepam. The analytes spiked into human serum were subjected to solid-phase extraction followed by liquid chromatography coupled with electrospray ionization tandem mass spectrometry. The running time was within 25 min for the measurement of 22 benzodiazepines and their metabolites. The recovery rates exceeded 58.1% for those compounds except for quazepam, which showed a recovery of 45.8%. The limit of detection ranged from 0.3 to 11.4 ng/mL. Linearity was satisfactory for all compounds. These data suggest that the present method can be applicable to routine assay for benzodiazepines in the clinical setting. 相似文献
912.
Itoh T Fukutani K Hino M Ihara E Inoue K 《Journal of colloid and interface science》2009,330(2):292-297
The effects of polystyrene-b-poly(aminomethyl styrene) (PSn-b-PAMSm) stabilizers on the particle size (Dn) and size distribution (PSD) in dispersion polymerization of styrene were investigated. The block copolymers, PSn-b-PAMSm, were prepared as follows: (i) atom transfer radical polymerization (ATRP) of styrene (PS-Br), (ii) ATRP of vinylbenzylphthalimide with the PS-Br (PS-b-PVBP), and (iii) treatment of the PS-b-PVBP with hydrazine. When the dispersion polymerization of styrene proceeded at 60 °C in ethanol with PS19-b-PAMS130 stabilizer, spherical polystyrene particles with Dn=0.91 μm (PSD = 1.01) were obtained. The particle size was strongly affected by the copolymer composition. With an increase in PAMS block length from m=54 to 100 in PS17-b-PAMSm, particle diameter became smaller from 1.55 to 0.91 μm. On the other hand, an increase in the length from m=20 to 82 in PS34-b-PAMSms caused an increase in particle size from 0.35 to 0.70 μm. Titration of the particles suggests that 14–81% of stabilizers used in the polymerization system were attached on the polystyrene particle surfaces, depending on the composition of the block copolymers. Thus, for the dispersion polymerization of styrene, PSn-b-PAMSm block copolymers have both functions as a stabilizer during polymerization and surface-modification sites of polystyrene particles. 相似文献
913.
Typical bacterial glycoconjugates are known to stimulate immunological systems of higher animals and thereby play important roles in the primary defense of animals against bacterial infection. Lipopolysaccharide (LPS) of gram‐negative bacteria is a representative of such glycoconjugates. LPS was first discovered as a potent bacterial toxin and named endotoxin but was soon found to exhibit immunostimulating activity. By the use of our synthetic pure preparations, the lipophilic partial structure of LPS, designated lipid A, proved to be the active entity responsible for both endotoxic and immunostimulating activities of LPS. This paper deals with our recent chemical synthesis and functional study of lipid A and related compounds. Synthesis is described of its various structural analogues, radio‐labeled compound and Re‐type LPS that contains two additional sugar moieties linked to lipid A. 相似文献
914.
Nakamura H Yamaguchi Y Miyazaki M Maeda H Uehara M Mulvaney P 《Chemical communications (Cambridge, England)》2002,(23):2844-2845
A micro-reactor was utilized for continuous and controlled CdSe nanocrystal preparation. Effects of reaction conditions on optical properties of the nanocrystals were investigated; in this current system, rapid and exact temperature control of the micro-reactor was beneficial for controlling particle diameter and reproducible preparation of particles; additional effort was made towards narrower particle-size distributions. 相似文献
915.
The combination of the water-soluble radical initiator, 2,2'-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride (VA-044), and surfactant, cetyltrimethylammonium bromide (CTAB), was found to be the most suitable condition for the effective direct synthesis of useful active thioesters (pentafluorophenyl thioesters) in water. 相似文献
916.
917.
We prove the unconditional security of the Bennett 1992 protocol, by using a reduction to an entanglement distillation protocol initiated by a local filtering process. The bit errors and the phase errors are correlated after the filtering, and we can bound the amount of phase errors from the observed bit errors by an estimation method involving nonorthogonal measurements. The angle between the two states shows a trade-off between accuracy of the estimation and robustness to noises. 相似文献
918.
Nakano K Doi K Tamura K Katsumi Y Tazaki M 《Chemical communications (Cambridge, England)》2003,(13):1544-1545
Glucose oxidase (GOx) has been attached covalently to form uniform enzyme monolayers on self-assembled monolayers (SAMs) from 11-aminoundecanethiol (AUDT) by taking advantage of chemical oxidation of GOx carbohydrate residues followed by coupling the resulting 'aldehydic' enzyme with the terminal amino group in the SAM as characterized by AFM imaging, IR, QCM, and electrochemical measurements. 相似文献
919.
Shimada S Rao ML Hayashi T Tanaka M 《Angewandte Chemie (International ed. in English)》2001,40(1):213-216
920.