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11.
Simultaneous separation and identification of hashish constituents by coupled liquid chromatography-mass spectrometry (HPLC-MS) 总被引:1,自引:0,他引:1
C. Rustichelli V. Ferioli F. Vezzalini M. C. Rossi G. Gamberini 《Chromatographia》1996,43(3-4):129-134
Summary This paper reports the use of liquid chromatography for the separation and determination of the major cannabinoids extracted from hashish samples. The direct coupling to the mass spectrometer enables the selective identification both of neutral and acidic cannabinoids. The developed method does not require any preliminary derivatization and should, therefore, be of interest in forensic analysis for simple and unequivocal determination of hashish constituents.Part of this work was presented at the 2nd Italian-Spanish Joint Meeting of Medicinal Chemistry, 30 August–3 September 1995, Ferrara, Italy. 相似文献
12.
荧光猝灭法测定人发中微量锰 总被引:3,自引:0,他引:3
张根成 《理化检验(化学分册)》2004,40(12):708-709
异丙肾上腺素在pH9.91的伯瑞坦 罗比森缓冲溶液中被MnO-4氧化,导致其荧光强度显著减弱。最大激发及发射波长为278nm和616nm,MnO-4浓度在0.01~0.64mg·L-1范围内,荧光强度与浓度呈良好线性关系。将其用于人发中微量锰的测定,得到满意的结果。 相似文献
13.
建立了散射背景下测定人体血清中Zn^2+含量的激光热透镜光谱分析方法。比较了蛋白质微粒散射对于分光光度法和激光热透镜光谱分析法测定的影响。结果表明,激光热透镜光谱分析方法能够避免溶液中存留蛋白质微粒散射的影响。Zn^2+量在0~1.6μg/mL范围内呈线性关系(r=0.9986),检出限为1ng/mL。应用于人体血清中Zn^2+含量的测定,与原子吸收法测定结果基本一致。 相似文献
14.
The multi-component isotherms for human insulin (HI) and desamido human insulin (dHI) over reversed phase packing (C18) and with 29.8% (w/w) ethanol-water as mobile phase have been determined experimentally. The isotherms of HI in ethanol-water differ from those obtained with the more commonly applied methanol-water and acetonitrile-water mobile phase, as described in this paper. The isotherm exhibits anti Langmuirian behavior and can be very well modeled by an anti Langmuir isotherm presented in this paper. The HI and dHI anti Langmuir isotherm are determined as: qHI = (8.4C(HI) + 3C(HI)CdHI)/(1 - 0.05C(HI) - 0.14CdHI + 0.04C(HI)CdHI) and qdHI = (11.4CdHI + 2C(HI)CdHI)/ (1 - 0.05C(HI) - 0.14CdHI + 0.04C(HI)CdHI) 相似文献
15.
16.
Abdel -Aziz M. Wahbi Mona M. Bedair Shereen M. Galal Mohamed H. Abdel-Hay Azza A. Gazy 《Mikrochimica acta》1993,111(1-3):83-91
A sensitive and rapid Spectrofluorimetric method for the determination of guanethidine sulphate, guanfacine hydrochloride, guanoclor sulphate and guanoxan sulphate in tablets and spiked human serum and urine samples is described. The method is based on the reaction of monosubstituted guanidino compounds in an aqueous potassium hydroxide solution with benzoin, in the presence of -mercaptoethanol and sodium sulphite. Highly fluorescent derivatives were obtained, with excitation and emission maximum wavelengths around 325 and 430 nm, respectively. In optimal reaction conditions, the linearity ranges were 0.04–0.28 g/ml, with relative standard deviations less than 2%. The method has been successfully applied to the determination of these drugs in tablets. The results are highly correlated with the B.P. method. Chloroform (or for guanoxan dichloromethane) was used to extract the drugs from serum and urine at basic pH, followed by the proposed fluorimetric method. The limit of detection is 0.02 g/ml for the selected drugs. 相似文献
17.
P.M.?Kosaka Y.?Kawano M.C.?Salvadori D.F.S.?PetriEmail author 《Cellulose (London, England)》2005,12(4):351-359
The adsorption of cellulose acetate (CA), cellulose acetate propionate (CAP) and cellulose acetate butyrate (CAB) from solutions
prepared in acetone onto silicon wafers led to ultrathin films, which were characterized by ellipsometry, atomic force microscopy
(AFM) and contact angle measurements. The polysaccharides films were characterized in the air just after their formation and
after annealing at temperatures higher than their glass transition temperature or melt temperature. The films thickness close
to 2 nm and surface roughness did not vary significantly upon annealing. AFM images revealed the presence of small clumps
dispersed on a homogeneous layer, which covered completely the Si wafers. Such topographic details were also observed after
annealing. However, upon annealing the films surfaces changed from hydrophilic to hydrophobic, evidencing molecular re-orientation
at the solid–air interface. The adhesion of bovine serum albumin (BSA) and lipase onto the cellulose esters films was quantified
in order to evaluate the possibility of applying such films as selective support for biomolecules. 相似文献
18.
19.
Diane Beauchemin 《Mikrochimica acta》1989,99(3-6):273-281
The certification of marine materials for trace metals is a process which challenges every technique involved, especially if a technique is as recent as inductively coupled plasma mass spectrometry (ICP-MS), Developmental work was required for several materials (natural waters, biological materials, marine sediments). It is reviewed here, in an attempt to show how one can take full advantage of ICP-MS. This includes a review of the digestion procedures developed for the multielement analysis of biological materials and marine sediments in order to minimize spectroscopic interferences. The multielement analysis of natural waters is also reviewed, in particular that of saline waters which requires a separation of the analytes from the alkali and alkaline earths elements and a preconcentration of the analytes on a column of silicaimmobilized 8-hydroxyquinoline. The potential of performing this separation/preconcentration procedure on-line is showed using both published and original results. Finally, the application of ICP-MS to speciation is illustrated by the determination of methylmercury in biological materials after extraction, and by the determination of arsenic species by high performance liquid chromatography coupled to ICP-MS.Presented in part at the 1989 European Winter Conference on Plasma Spectrochemistry, Reutte, AustriaThe work described was carried out while the author was a Research Associate at the Analytical Chemistry Section, Chemistry Division, National Research Council of Canada, Ottawa, K1A OR9, Canada 相似文献
20.
Nicolas Le Calvez 《中国化学会会志》2002,49(4):585-592
The aim of this study was to develop an analytical method to determine the organochlorine concentrations in sediments. Combination of Microwave assisted Solvent Extraction (MASE) and capillary gas chromatography with specific detection (electron capture detector) was a viable approach for the determination of pesticides in solid matrixes. In this study, MASE development was focused on the selection of a suitable extraction solvent for all the target analytes. MASE procedure was validated by comparison with conventional methods such as Soxhlet and sonication extraction. The proposed method was then applied to determine the organochlorine insecticides concentrations in samples from Authie Bay (France). Environmental water samples were analysed and five target analytes were detected in concentrations from 0.03 to 0.56 ng/g of dry sediment. These investigations showed the accumulation and the persistency of these products in sediments in spite of the fact they were banned a few decades ago. 相似文献