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771.
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A high‐performance liquid chromatography method for simultaneous separation and determination of biogenic amines [dopamine, epinephrine, serotonin and its six metabolites (normetanephrine, metanephrine, 3,4‐dihydroxyphenylacetic acid, 4‐hydroxy‐3‐methoxyphenylglycol, homovanilic acid and 5‐hydroxyindoloacetic acid)] with drugs from different therapeutically groups [analgesics (paracetamol, metamizol), diuretics (furosemide) and antibiotics (cefazolin, fluconazole)] was developed. A chromatographic column with pre‐column with octadecylsilane phase (C18e) and two detectors – diode array serial connected and fluorescence – was used. Gradient elution of mixture of acetate buffer (pH 4.66) and methanol as a mobile phase was applied. The limit of detection (LOD) of 8–10 ng/mL and limit of quantitation (LOQ) of 24–30 ng/mL for biogenic amines, as well as the LOD of 50–100 ng/mL and the LOQ of 150–300 ng/mL for drugs, were determined. The applied sample preparation method allowed recoveries of 93% for the biogenic amines and 92% for the drugs to be achieved. The developed procedure has been applied to simultaneous determination of the examined compounds in urine samples and could be used in clinical analysis. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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774.
Maja Miletić Dragana Vuković Irena Živanović Ivana Dakić Ivan Soldatović Dejan Maletić Saša Lazović Gordana Malović Zoran Lj. Petrović Nevena Puač 《Central European Journal of Physics》2014,12(3):160-167
In numerous recent papers plasma chemistry of non equilibrium plasma sources operating at atmospheric pressure has been linked to plasma medical effects including sterilization. In this paper we present a study of the effectiveness of an atmospheric pressure plasma source, known as plasma needle, in inhibition of the growth of biofilm produced by methicillin resistant Staphylococcus aureus (MRSA). Even at the lowest powers the biofilms formed by inoculi of MRSA of 104 and 105 CFU have been strongly affected by plasma and growth in biofilms was inhibited. The eradication of the already formed biofilm was not achieved and it is required to go to more effective sources. 相似文献
775.
Angelika Baranowska‐Ła̧czkowska Wojciech Bartkowiak Robert W. Góra Filip Pawłowski Robert Zaleśny 《Journal of computational chemistry》2013,34(10):819-826
Static longitudinal electric dipole (hyper)polarizabilities are calculated for six medium‐sized π‐conjugated organic molecules using recently developed LPol‐n basis set family to assess their performance. Dunning's correlation‐consistent basis sets of triple‐ζ quality combined with MP2 method and supported by CCSD(T)/aug‐cc‐pVDZ results are used to obtain the reference values of analyzed properties. The same reference is used to analyze (hyper)polarizabilities predicted by selected exchange‐correlation functionals, particularly those asymptotically corrected. © 2012 Wiley Periodicals, Inc. 相似文献
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777.
The efficient synthesis of 3-, 4-, and 5-O-feruloylquinic acids starting from d-(?)-quinic acid is described. Esterification of suitably protected quinic acid derivatives with 3-(4-acetoxy-3-methoxyphenyl)-acryloyl chloride and subsequent hydrolysis of all the protecting groups afforded the title products in overall yields of 33%, 15%, and 45%, respectively, (from quinic acid). 相似文献
778.
779.
George Georgiev Anna Tzoneva Lyudmil Lyutov Stefko Iliev Irena Kamenova Ventseslava Georgieva Elena Kamenska Andreas Bund 《Macromolecular Symposia》2004,210(1):393-401
The precipitation temperature (Tpr) value of aqueous poly(dimethylamino-ethoxyacryloyl-propylsulphonate) (PDMAPS) solutions decreases with the rise of electric field intensity both in the absence and in the presence of a low molecular salt. This electrostimulated Tpr shift is explained qualitatively by means of the model taking into account both the dominating intermacromolecular dipole-dipole interaction and the dipole cluster formation. 相似文献