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81.
Determination of binding affinity of enantiomers to albumin by liquid chromatography 总被引:1,自引:0,他引:1
The principles of the determination of the binding affinity constants of small molecules to albumin by liquid chromatography, using albumin as a mobile phase additive, are outlined. Chromatographic conditions for determinations of constants are presented and applied to enantiomers of tryptophan and omeprazole. The influence of albumin on the retaining properties of LiChrosorb RP-8, Phenyl Hypersil and LiChrosorb Diol was studied. 相似文献
82.
Rolf Pettersson 《Journal of statistical physics》1993,72(1-2):355-380
This paper considers the linear space-inhomogeneous Boltzmann equation for a distribution function in a bounded domain with general boundary conditions together with an external potential force. The paper gives results on strong convergence to equilibrium, whent, for general initial data; first in the cutoff case, and then for infinite-range collision forces. The proofs are based on the properties of translation continuity and weak convergence to equilibrium. To handle these problems generalH-theorems (concerning monotonicity in time of convex entropy functionals) are presented. Furthermore, the paper gives general results on collision invariants, i.e., on functions satisfying detailed balance relations in a binary collision. 相似文献
83.
Khriachtchev L Macoas E Pettersson M Rasanen M 《Journal of the American Chemical Society》2002,124(37):10994-10995
The trans and cis forms of formic acid (HCOOH) in solid argon favor essentially different photodissociation (193 nm) products, H2O + CO and H2 + CO2, respectively. The branching ratio of these channels differs between the two conformers by a factor of >10. The observed selective photodissociation features conformational memory when the transition state of a molecule is reached before torsional randomization. These data demonstrate that the photodissociation products can be efficiently steered with selective narrow-band infrared radiation promoting rotational isomerism, which makes a strong case of optically controlled chemical reactions 相似文献
84.
A simple and sensitive procedure for the routine assay of the analgesic drug dextropropoxyphene and its main metabolite, norpropoxyphene, in plasma is described. After liquid-liquid extraction from alkalinized plasma and back-extraction into a small volume of an acidic aqueous phase, the aqueous phase was injected into a column packed with 3-microns octadecylsilica particles. Ultraviolet absorbance detection at 210 nm was used. Concentrations down to 2 nM could be determined for both compounds; at this level, the intra-assay coefficient of variation was 5%. 相似文献
85.
Summary Chiral resolution of aminoalcohols is performed by ionpair chromatography using (+)-10-camphorsulphonic acid in methylene chloride + 1-pentanol (1991) as mobile phase and LiChrosorb DIOL as adsorbing stationary phase. Change of the properties of the solid phase and the nonpolar solvent affects the retention and the separation efficiency but has no significant influence on the chiral selectivity. Studies of the structural requirements for the stereoselective separation have shown that a simultaneous electrostatic and hydrogen bonding between the two enantiomeric ions is of fundamental importance. Studies of equilibrium processes in the mobile phase indicate that the aminoalcohols are retained as ion pairs.Presented at the 14th International Symposium on Chromatography London, September, 1982 相似文献
86.
A cold trap system for the determination of selenium by hydride generation-atomic absorption spectrometry (HG-AAS) is described. For a 30-ml sample the limit of detection is <2 ng/l. and the precision is better than 4% at the 30 ng/l. level. A number of digestion procedures for the destruction of organic matter prior to the determination of total dissolved selenium in water has been tested and compared. Concordant results were obtained except for oxidation by peroxodisulphate in strongly acidic solutions with a high content of organic material. The selenium concentrations found were in agreement with those obtained by HG-AAS after preconcentration by evaporation and dry ashing with the magnesium nitrate-nitric acid-hydrochloric acid method. 相似文献
87.
Otto Pettersson 《Fresenius' Journal of Analytical Chemistry》1886,25(1):479-484
Ohne ZusammenfassungMittheilung aus dem Laboratorium der Stockholmer Hochschule.Hierzu Tafel I, Figur 5-6. 相似文献
88.
Analytical and Bioanalytical Chemistry - 相似文献
89.
In connection with our 13C NMR investigations we were interested in obtaining pure samples of 2- and 3-chlorofuran and 2- and 3-chloroselenophene. While direct chlorination with molecular chlorine or other chlorinating agents can successfully be used for the preparation of 2-chlorothiophene,1 we could not reproduce either yields or isomeric purity in the corresponding chlorination of selenophene.2,3 相似文献
90.