to any single method for trace-element analyses. In regard to whether the method is applicable to serum or plasma with abnormal viscosity: our method was not developed for the analysis of serum. Plasma is the preferred sample, for reasons previously reported (1, 8). However, for samples diluted fivefold the aspiration rates for plasma and serum are identical. We have not studied plasma with abn...

background and aims: a selective and sensitive high performance liquid chromatography-electrospray ionization mass spectrometry method has been established for determination of methotrexate in human plasma. methods: methotrexate was extracted from plasma with acetonitrile. the mobile phase consisted of acetonitrile-water-formic acid 74: 25: 1(v/v). twenty µl of sample was chromatographically an...

the present work describes a reverse phase hplc method for the quantitation of drotaverine hydrochloride and mefenamic acid in human plasma. organic solvent system used for liquid extraction composed of dichloromethane, and isopropyl alcohol in the ratio 80:20 (v/v). the compounds were separated on a thermo bds hypersil c8 (25.0 cm×4.6 mm, 5 µm particle size) column in isocratic mode with a mix...

this paper presents the results of a study on the radiation characteristics of a plasma triangular antenna in the vhf band (30-300mhz) applying the method of moment. deriving the current distribution of the antenna, it shows the relationship between radiation characteristics of the plasma antenna and the plasma parameters. both theoretical and numerical results indicate that if the plasma frequ...

A sensitive chemiluminescence (CL) method was developed for determining melamine in urine and plasma samples based on the fact that melamine can remarkably enhance the chemiluminescence of Luminol-K3 Fe(CN)6 system in alkaline medium. The determination conditions were optimized. Under optimum conditions, the chemiluminescence intensity had a good linear relationship with melamine in the range o...

Improved detection efficiency and microdroplet sample introduction in single particle inductively coupled plasma mass spectrometry allow for accurate sizing counting of nanoparticles suspension at the digit nm scale.

A simple, sensitive, selective and reproducible method based on reversed-phase chromatography was developed for the determination of ivermectin in human plasma. The internal standard (moxidectin) was separated from ivermectin on a Hypersil Gold C18 column (150 x 4.6 mm, 5 microm particle size), with retention time of 3.7 and 7.0 minutes, respectively. Fluorescence detection was set at an excita...

A specific, accurate liquid-chromatographic/mass-spectrometric (HPLC/MS) method for measurement of cholesterol sulfate in plasma from normal individuals and patients with recessive X-linked ichthyosis (RXLI) is described. The method is superior to previously described techniques because it measures the analyte intact rather than after hydrolysis. Traces of free cholesterol in the sample analyze...