ABSTRACT
ObjectiveTo develop a analytical method of three phenoxyalkanoic acid herbicides,MCPA,2,4-D and dichlorprop,in grape leaf using dichloropropyl esterification and gas chromatography with electron-capture detection.MethodsSamples were pounded to pieces,added into internal standard 2,4-dichlorophenylacetic acid,acidified and extracted with ethyl ether.The extracts were cleaned up by liquid-liquid partition.The cleaned organic solutions were evaporated and the residues were dichloropropylated using sulfuric acid and 1,3-dichloropropan-2-ol.The formed esters were analysed by gas chromatography.ResultsThe detection limits of MCPA,2,4-D and dichlorprop in grape leaf were 20ng/g,20ng/g,and 30ng/g,respectively.The concentritions of herbicides in grape leaf were linear over the ranger 100~1000ng/ml.The average recoveries of MCPA,2,4-D and dichlorprop in spiked grape leaf at concentrition of 200ng/g were 98.8%,101.3% and 103.1% with the coefficients of variation 11.4%,11.0% and 9.3% respectively.ConclusionThis method is sensitive and accurate for determination of these three herbicides in poisoned grape leaf.
ABSTRACT
A method was developed to assay α-Hydroxyltriazolam and α-Hydroxyalprazolam, which are the major metabolites of triazolam and alprazolam respectively,in human urine. After addition of 2-hydroxyflurazepam (interal standard) and hydrolysis with β-glucuronidase, the hydroxy-metabolites were extracted with hexane-dichloromethane (1∶1) at pH 10.8, then were derivated with (BSTFA). The analysis was performed on a HP-5 capillary column with electron-capture detector.The detection limits of analysis in urine were about 1μg/L.The method was successfully applied to urine specimens collected from healthy human volunteers who ingested 0.5 mg of triazolam or 0.8 mg alprazolam. The method was enough sensitive to assay urine specimen excreted at 24 h by volunteers after taking the medicine.
ABSTRACT
Objective A method for the analysis of eleven benzodiazepine in beverages,blood and urine and seven main metabolites of benzodiazepine in urine by solid phase extraction and high performance thin layer chromatography is described in this paper.Method The analytic materials in specimens were extracted by using GDX 101 porous resin as absorbent and diethyl ether as eluant.The extracts were spread out on plates using benzene∶acetone(10∶6) as eluant and were visualized by modified Dragendorffs reagent.Results The absolute sensitivity of the analysis is 0 4 ?g to 0 6 ?g .The limit of detection of benzodiazepines in urine,blood and beverages are 0 4 ?g/ml to 1 0 ?g/ml ,0 6 ?g/ml to 1 0 ?g/ml and 0 4?g/ml to 0 8 ?g/ml respectively.The limits of detection of metabolites of benzodiazepines in urine are 0 4 ?g/ml to 1 0 ?g/ml .Conclusion These results suggested that this method is useful for the detection of benzodiazepines in toxication case.
ABSTRACT
A comprehensive approach to the quantitative determination of sodium-diphacinone in human andrabbits organ tissues samples based on solid-phase extraction and derivative spectrophotometry hasbeen developed. This procedure, using acetonitrile to precipitate protein of tissues and GDX403(polymeric resine made in China) as absorbent in solid-phase extraction, was sufficientIy simple,rapid and cheaper. Results of this method was also reliable- Recoveries of sodium-diphacinone fromspiked tissues were around 70% at levels from 5 to 40pg/g. The detection limits of about 1 ?g/g forsodium-diphacinone could be achieved.
ABSTRACT
Objective A rapid and highly sensitive method, based on the high performance thin-layer chromatography, was described for the qualitative and semiquantitative determination of 7-aminon-itramepam, the main metabolites of nitramepam, in human urine. Method 7-aminonitramepam was extracted by diethyl ether under pH9 condition. Fluorecsamine was used as a reagent to produce fluorescent product to show analyte on plate. Results The limit of detection for 7-aminonitramepam in urine was 5ng/ ml and the limit of quantitation was 15ng/ml. Conclusion The method can be successfully used for determining 7-aminonitramepam in urine samples excreted over 48h period after receiving 10mg nitramepam o-rally and could be applied to drug examination for the cases of drug-facilitated rob.