ANALYSIS OF ETHACRYNIC ACID IN URINE BY HPLC-FLUORESEENCE DETECTOR

A sensitive and selective method has been developed for the detection of free ethacrynic acid in human urine. Using 4-(bromomethyl)-7-methoxycoumarin, ethacrynic acid was transformed into a fluorescent derivative, and was analysed by HPLC-fluorescence detector. The detection limit is 0.1ug/ml urine. The method is suitable for screening ethacrynic acid in doping control and studying its metabolism.

GAS CHROMATOGRAPHIC-MASS SPECTROMETRIC ANALYSIS OF ANABOLIC STEROIDS IN HUMAN URINE

A new GC/MS method for detection and identification of 19 anabolic steroids in human urine is presented.The procedure involves adsorption and isolation on a macroporous XAD-2 resin,enzymatic hydrolysis,alkaline extraction,derivatization,GC separation and MS detec- tion.Gas chromatographic-mass spectrometric data illustrate artifacts arising from enzymatic hydrolysis of steroid glucuronides and the structural characterization of their metabolites. Using this method,metabolic studies of these steroids in human urine were made after their ingestion by normal and healthy male volunteers.This method was proven to be suitable for large-scale routine analysis of anabolic steroids and was used successfully in passing the doping control test held by the Medical Commission of the International Olympic Committee.

Capillary electrophoresis with electrochemiluminescence detection for the analysis of quinolone drugs and pharmacokinetics study

A novel method for the determination of two quinolone drugs norfloxacin （NOR） and levofloxacin （LVX） was described by capillary electrophoresis with electrochemiluminescence detection. The good relationship （r ≥ 0.9991） between peak area and concentration of analytes was established over two orders of magnitude. The limits of detection （LOD, S/N = 3） in standard solution are 4.8 × 10^-7 mol/L for NOR and 6.4 × 10^-7 mol/L for LVX, respectively. The limits of quantitation （LOQ, S/N = 10） in real human urine samples are 1.2 × 10^-6 mol/L for NOR and 1.4 × 10^-6 mol/L for LVX, respectively. The present method was successfully applied to the determination of NOR and LVX in human urine and the studv of oharmacokinetics of NOR.

Urinary Schistosomiasis Prevalence and Diagnostic Performance of Reagent Strip at Point-of-Care

Due to limited resources and experience, rapid diagnostic techniques are advocated in nations with a resource shortage when diagnosing schistosomiasis. We used rapid diagnostic tests to access the prevalence and intensity of schistosome infection in North Central, Nigeria. A total of 1951 participants were recruited for this study. The participants were screened for S. haematobium infection;haematuria and proteinuria were monitored in the recruited patients with a commercial reagent strip. Of the 1951 participants recruited for the study, 587 were found to be infected. Children aged 0 to 10 years showed the highest levels of haematuria with (100%) specificity. Meanwhile, other age groups (11 - 20, 21 - 30, 31 - 40 and above 40 years) had rates higher than 90%. The degree of haematuria increased with egg intensity. The same was seen in proteinuria, with a percentage of 41.9%. A significant difference (p S. haematobium in rural endemic areas.

Determination of diastereoisomeric alkaloids in urine by capillary electrophoresis with electrochemiluminescence detection

A new and simple capillary electrophoresis with electrochemiluminescence detection was developed for the separation and the quantification of a pair of diastereoisomenc alkaloids（ephedrine and pseudoephedrine）.The limits of detection（S/N = 3） were 4.5×10^-8 mol/L for ephedrine and 5.2×10^-8 mol/L for pseudoephedrine,respectively.The RSDs of migration time and peak area were less than 1.3 and 2.5%（n = 5）,respectively.The applicability of the propose method was illustrated in the determination of ephedrine and pseudoephedrine in human urine,ephedrine in nasal drops,and the monitoring of pharmacokinetics for pseudoephedrine.

Effects of Dietary Intake of Arsenosugars and Other Organic Arsenic Species on Studies of Arsenic Methylation Efficiency in Humans

Extensive research has used dimethylarsinic acid(DMA)in urine as a marker of arsenic methylation.The premise is that humans methylate inorganic arsenicals to monomethylarsonic acid(MMA)and DMA and excrete these arsenic species into the urine.However,DMA in urine not only comes from the methylation of inorganic arsenic but also could be a result of metabolism of other arsenic species,such as arsenosugars and arsenolipids.Most environmental health and epidemiological studies of arsenic methylation might have overlooked confounding factors that contribute to DMA in urine.Here we critically evaluate reported studies that used methylation indexes,concentration ratios of methylated arsenicals,or the percentage of DMA in urine as markers of arsenic methylation efficiency.Dietary intake of arsenosugars potentially confounds the calculation and interpretation of the arsenic methylation efficiencies.Many studies have not considered incidental dietary intake of arsenosugars,arsenolipids,and other organic arsenic species.Future studies should consider the dietary intake of diverse arsenic species and their potential effect on the urinary concentrations of DMA.