Optimization and validation of a highly sensitive method for determining glyphosate in human urine by solid-phase extraction and liquid chromatography with tandem mass spectrometry: a methodological study

BACKGROUND@#Glyphosate and its salt formulations are nonselective herbicides that have been extensively used worldwide, both for residential and agricultural purposes. The possible carcinogenicity and teratogenicity of glyphosate remain to be elucidated. We developed a sensitive and high-throughput analytical method for urinary glyphosate using liquid chromatography-tandem mass spectrometry with the aim of contributing to glyphosate exposure assessment in epidemiological studies.@*METHODS@#After urine dilution (creatinine matching dilution to 0.05 g creatinine/L), glyphosate was extracted using two types of solid phase extraction columns (SCX and NH2) with automated sample preparation instruments. The eluate was dried and dissolved in the mobile phase, followed by liquid chromatography-tandem mass spectrometry analysis. The optimized method was applied to urine samples obtained from 54 Japanese adults and children.@*RESULTS@#The results from the validation study demonstrated good recoveries (91.0-99.6%), within- and between-run precisions (< 15%), low detection limits (0.1 μg/L), and lower limit of quantification (0.3 μg/L). The detection frequency and median concentration of the urinary glyphosate in Japanese subjects were 59% and 0.25 μg/L (0.34 μg/g creatinine).@*CONCLUSIONS@#Our reliable determination method was successful in measuring urinary glyphosate concentration. Moreover, this is the first biomonitoring report of urinary glyphosate levels in the Japanese general population.

Avaliação da remoção de interferentes endócrinos, ativos farmacêuticos e cafeína em água para abastecimento público do estado de São Paulo / Assessment of endocrine disruptors, pharmaceuticals and caffeine removal in drinking water of the São Paulo State

Alguns compostos orgânicos como interferentes endócrinos e ativos farmacêuticos estão sendo encontrados em águas superficiais e vêm chamando a atenção de orgãos públicos e da comunidade científica. Dentre esses compostos, foram enfatizados nesse trabalho, o hormônio sintético 17α-etinilestradiol, o surfactante (4-nonilfenol), bisfenol A, o antibiótico ß-lactâmico amoxicilina e a cafeína como traçador de atividade antrópica. Estes compostos são continuamente introduzidos em corpos d'água pelo lançamento de esgoto in natura o que afeta a qualidade da água, a saúde dos ecossistemas e impacta o suprimento de água potável. Considerando a baixa taxa de remoção desses contaminantes pelo tratamento de água atualmente utilizado no Brasil e o estado de degradação dos mananciais de água para abastecimento público, esse trabalho apresenta o desenvolvimento de metodologia analítica para determinação dos compostos citados e a avaliação da eficiência de remoção quando o tratamento convencional de água é aplicado. A determinação foi baseada em métodos já estabelecidos e envolveram as etapas de limpeza e concentração de amostra usando extração em fase sólida (SPE) e análise por cromatografia a líquido de alta eficiência (HPLC) com detector de arranjo de diodos (DAD) e espectrometria de massas. As amostras do Reservatório do Guarapiranga foram utilizadas para ensaios em escala laboratorial que simulavam o tratamento convencional de água em planta real. Os resultados mostraram a adequação dos métodos utilizados para a separação e determinação desses compostos em amostras ambientais. Além disso, apontaram para a necessidade de se avaliar a utilização de metodologias não convencionais que otimizem a remoção pelo tratamento de água atualmente utilizado

Some organic compounds, such as endocrine disruptors and pharmaceuticals, are being found in the surface water, and are concerning both the public organs and the scientific community. Among these compounds, the synthetic hormone 17α-ethinylestradiol, the surfactant (4-nonylphenol), bisphenol-A, the ß-lactam antibiotic amoxicillin and the marker of human activity caffeine were highlighted in the present work. These compounds are continuously drained to the water bodies by sewers, affecting not only the water quality itself, but also the ecosystems, and impacting the drinking water availability. Currently in Brazil, the removal rate of these contaminants is low, whereas the water sources for public supply are highly degraded. In this context, the present work develops an analytical method to detect the aforementioned compounds, and to evaluate the efficiency of its removal by conventional water treatments. Detection was based on pre-established methods and steps involved clean up and samples concentration by solid phase extraction (SPE), high performance liquid chromatography with diode array detection (DAD), and mass spectrometry. Recovery tests were done using environmental samples from Guarapiranga Reservoir (São Paulo, SP). This samples were further used in laboratorial tests, simulating real scale water conventional treatments. Current results revealed the adequacy of the chosen methods in the separation and determination of the abovementioned compounds from natural samples. Also, they highlight the need for the evaluation of non-conventional methodologies that optimize removal by current water treatment

Determination of doxepin in whole blood by SPE-LC-MS/MS / 法医学杂志

OBJECTIVE@#To develop a method of SPE-LC-MS/MS for the determination of doxepin in whole blood.@*METHODS@#After solid phase extraction, the samples were identified by LC-MS/MS. Positive ion electrospray ionization mode and multiple reaction monitoring (MRM) mode was selected. Amitriptyline was used as internal standard. The m/z of doxepin: 280-->107, 280-->235 and 280-->220. The m/z of amitriptyline: 278-->233. The retaining time of doxepin and amitriptyline were 15.15 and 16.94 min, respectively.@*RESULTS@#The calibration curve was linear among the concentration of doxepin range from 0.005 to 1.00 microg/mL. The linear correlation equation was y = 3.2047x + 0.0339, the correlation coefficient was 0.9996. The detection limit of doxepin was 0.001 microg/mL and average recovery rate was 78.0%-82.9%. The relative standard precision for within-day and between-day were less than 2.55% and 5.90%, respectively.@*CONCLUSION@#The method is effective, simple, reliable and can be used in the determination of doxepin in whole blood.

Analysis of imatinib in bone marrow and plasma samples of chronic myeloid leukaemia patients using solid phase extraction LC-ESI-MS

The LC-ESI-MS was developed and validated for the analysis of imatinib in plasma and bone marrow samples using deuterated imatinib [D[8]-IM] as an internal standard. The biological samples were extracted using Strata-X-C SPE cartridges and separated on C[8] column [50 x 3 mm, 3 microm], and methanol: 0.1% formic acid [70:30] was delivered at the rate of 0.7 ml/min as a mobile phase. Imatinib was quantified in samples by monitoring the ions m/z 494.3 for imatinib and 502.3 for D[8]-imatinib on mass spectrometer. The method was linear in the concentration range of 1-1500 ng/250 microl in spiked human plasma samples and limit of quantification was 5 ng/mL. Inter-day and intra-day variations in spiked human plasma spiked with 50, 250 and 500 ng /mL were less than 3.16%. The repeatability and reproducibility and other parameters of the methods were also validated. The method was employed for the analysis of the imatinib in human plasma and bone marrow samples. The drug levels in bone marrow and plasma samples were correlated to the degree of cytogenetic response. No significant difference of imatinib level between blood and bone marrow in IM-treated patients dosed to steady state was observed

A study in extraction method of buprenorphine in urine / 法医学杂志

OBJECTIVE@#The extraction method for separating buprenorphine from urine was described.@*METHODS@#Buprenorphine was extracted with chloroform at pH7 or with SPE (extracted by organic support 401 at pH10.8, then eluted with chloroform), finally determined by GC-NPD.@*RESULTS@#The extracted yields of the analyte in specimens were 86.6% by solution-phase extraction and 83.0% by solid-phase extraction (SPE) respectively.@*CONCLUSION@#These two methods are simple and accurate for separating buprenorphine from urine.

Analysis of 37 drugs in whole blood by HPLC after solid phase extraction / 法医学杂志

OBJECTIVE@#To develop a specific, sensitive, reproducible SPE-HPLC method for the determination of 37 drugs in whole blood.@*METHODS@#With the doxapram as internal standard, Oasis column was used to extract drugs from whole blood. Two kinds of mobile phases were used in this study. Separations were achieved by a LiChrospher 100 RP-C18 (250 mm x 4.0 mm x 5 microm) column kept at 50 degrees C, the DAD detector was set at 230 nm and 250 nm.@*RESULTS@#The limit of detection were 1-30 ng/mL. The method showed excellent linearity and the linear correlation coefficient was > or =0.997 98. The relative standard deviation for between-day and within-day assay were <10%.@*CONCLUSION@#The method is effective, simple, reliable and has been used in real cases.