Novel psychoactive substances (NPS) represent a great challenge to toxicologists due to the ability of illicit drug manufacturers to alter NPS chemical structures quickly and with ease to circumvent legislation regulating their use. Each time a new structure is introduced, there is a possibility that it has not been previously recorded in law enforcement or scientific databases. Many toxicology laboratories use targeted analytical methods that rely on libraries of known compounds to identify drugs in samples. However, these libraries do not include large numbers of NPS which could result in non-identification or detection. High-resolution mass spectrometry (HRMS) has been suggested as a method for screening a wide variety of analytes due to its higher sensitivity and mass accuracy as compared to some other forms of mass spectrometry. This technique can generate characteristic MS/MS spectral data for use in compound identification. The main goal of this research was to create a high-resolution mass spectrometry (HRMS) library of NPS and metabolites, as well as validate a method for screening and confirmation of these substances. The study consisted of three main tasks which included; the development of a large high-resolution MS/MS spectral library and database, validation of a method for screening and confirmation of over 800 NPS and metabolites, and screening of blind-spiked and authentic urine specimens to determine real-world applicability of the HRMS library and method. During validation, several isomeric and structurally related NPS were observed which could not be adequately separated using traditional LC methods. A fourth task was therefore added to investigate improved separation using two-dimensional liquid chromatography (2D-LC). Increased resolving power is achieved in 2D-LC through the coupling of multiple orthogonal separation systems. Ultimately, an on-line, comprehensive method was developed using orthogonal reversed-phase columns in each dimension (RP x RP) for improved separation of co-eluting and isomeric synthetic cannabinoids. This work can aid laboratories in the identification of NPS through the use of a validated LC-QTOF-MS method for screening and confirmation and HRMS spectral library. In instances where isomeric and structurally related NPS are not sufficiently separated, RP x RP methods can be explored.

No description available.

Novel psychoactive substances (NPS) are synthetic drugs that pose serious public health and safety concerns as their ingestion by recreational drug users continues to cause adverse events and death. A multitude of NPS have been implicated in forensic investigations in the United States, but the identification of these emerging substances is challenging and complex, requiring advanced analytical capabilities and novel analysis workflows. The most common and effective manner for identifying NPS is by the use of mass spectrometry, while the true utility of this technology lies within non-targeted acquisition techniques. This research sought to utilize novel drug screening technologies and customized methodologies to characterize current NPS use in high risk populations through the analysis of biological sample extracts discarded from a partnering forensic toxicology reference laboratory. Specifically, NPS detection, identification, and characterization were the primary foci to produce increased awareness and education on a national level. To accomplish these goals, two novel workflows were developed: sample mining and data mining. A liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) assay was developed, validated, and implemented for forensic toxicology analytical testing. A SCIEX TripleTOF™ 5600+ QTOF-MS with SWATH® acquisition coupled to a Shimadzu Nexera XR UHPLC was used. Resulting data were compared against an extensive in-house library database containing more than 800 analytes. The LC-QTOF-MS assay was applied to the re-analysis of biological sample extracts to discover emergent NPS, their metabolites, and trends in use patterns. In total, 3,543 biological sample extracts were analyzed during this research and 21 emerging NPS were detected, some for the first time, through sample mining. Among these emerging substances were the NPS opioids: isopropyl-U-47700, 3,4-methylenedioxy-U-47700, and fluorofuranylfentanyl; the NPS opioid precursors: N-methyl norfentanyl and benzylfuranylfentanyl; the NPS hallucinogens: 2F-deschloroketamine, methoxy-PCP, and hydroxy-PCP; the NPS stimulants: 3,4-methylenedioxy-alpha-PHP, eutylone, and N-ethyl hexedrone; and the NPS benzodiazepine: flualprazolam. With respect to trends, NPS opioid positivity declined over time during this research; however, fentanyl positivity was persistent. Heroin and 3,4-methylenedioxymethamphetamine (MDMA) positivity appeared to decline slightly, but further temporal evaluation is necessary. NPS were less likely to be found in combination with other NPS; only one NPS substance was found in 82.5% of NPS-positive samples. Fentanyl poly-drug use was common, including concurrent or proximate use with traditional opioids (42.8%), NPS opioids (27.3%), cocaine (26.4%), methamphetamine (13.1%), NPS stimulants (4.2%), and other substances. The evaluation of in vitro metabolism for five emerging NPS detected for the first time during this research (3,4-methylenedioxy-U-47700, ortho-fluorofuranylfentanyl, 2F-deschloroketamine, eutylone, and N-ethyl hexedrone) resulted in the characterization of major metabolic pathways and the identification of metabolites presence in vivo by data mining of extract datafiles. These major metabolites provide utility for forensic laboratories to prolong detection windows for NPS. The primary metabolite identified for 3,4-methylenedioxy-U-47700 was N-demethyl-3,4-methylenedioxy-U-47700; the primary metabolite identified for ortho-fluorofuranylfentanyl was fluoro-4-ANPP; the primary metabolite identified for 2F-deschloroketamine was 2F-deschloro-norketamine; and the primary metabolites identified for eutylone and N-ethyl hexedrone were products of hydrogenation to the beta-ketone. As shown through this research, NPS continue to appear in forensic toxicology casework and novel assays for their detection and characterization are critical to remaining at the forefront of emerging drug trends and recreational drug use. LC-QTOF-MS was a vital piece of the analytical puzzle for discovering and characterizing emerging NPS and their metabolites. Analytical chemists must continue research involving NPS to broaden our understanding of synthetic drugs and their public health and safety impacts. / Chemistry

A presença de compostos de uso veterinário em produtos de origem animal é uma grande preocupação em termos de saúde pública. A utilização descontrolada de antibióticos como medicamentos veterinários pode levar ao desenvolvimento de resistência bacteriana, podendo prejudicar a eficácia destas drogas no uso em humanos. Os aminoglicosídeos são antibióticos extensivamente utilizados na criação de animais para o tratamento de infecções bacterianas ou para a promoção do crescimento. A União Europeia estabeleceu níveis máximos de resíduos permitidos (LMRs) para os aminoglicosídeos em vários alimentos de origem animal. O governo brasileiro implementou um plano de controle que avalia os resíduos de medicamentos veterinários em produtos de origem animal. Neste trabalho, foram desenvolvidos método quantitativo por cromatografia a líquido acoplada a espectrometria de massas triplo quadrupolo em modo tandem (LC-MS/MS) e método de screening utilizando cromatografia a líquido acoplada a espectrometria de massas com analisador por tempo-de-voo (LC-qTOF-MS) para a determinação simultânea dos aminoglicosídeos espectinomicina, tobramicina, gentamicina, kanamicina, higromicina, apramicina, estreptomicina, diidroestreptomicina, amicacina e neomicina em leite e em músculo bovino, de aves e suíno. Como método de extração utilizou-se procedimento com ácido tricloroacético e clean up por precipitação a baixa temperatura e C18 a granel. Os métodos por LC-MS/MS e LC-qTOF-MS foram validados de acordo com a Diretiva da Comissão Europeia 2002/657/CE. Os resultados obtidos no método quantitativo para recuperação, precisão, linearidade, especificidade, limites de decisão (CCα) e capacidades de detecção (CCβ) nestas matrizes foram considerados satisfatórios. Os dados de limite de detecção (LOD) e limite de quantificação (LOQ) foram estabelecidos a partir dos LMRs, variando de 5 a 100 ng g-1 para LOD e 12,5 a 250 ng g-1 para LOQ. As recuperações variaram de 36,8 a 98%, e os coeficientes de variação ficaram entre 0,9 e 20,2%, observando-se que todas as curvas foram feitas com nas próprias matrizes a fim de minimizar os efeitos de matriz que são intrínsecos para os casos estudados neste trabalho. Os valores de CCβ obtidos no método qualitativo foram entre 25 e 250 ng g-1, considerados satisfatórios para os analitos nessas matrizes. O método proposto mostrou-se simples, fácil e adequado para a análise de um grande número de amostras por dia a um baixo custo. / The presence of several substances in animal products has been a major public concern. The use of antibiotics drugs as veterinary medicines might lead to the development of bacterial resistance, which might undermine the efficacy of these drugs in human use. The aminoglycosides are antibiotics that have been extensively employed in animal husbandry for the treatment of bacterial infections, but also as growth promotion. The European Union has issued strict maximum residue levels (MRLs) for aminoglycosides in several animal origin products. The Brazilian government implemented a control plan that assesses the residues of veterinary medicines in animal products. A quantitative method based on liquid chromatography tandem mass spectrometry (LC–MS/MS) and a screening method by liquid chromatography mass spectrometry with time-of-flight system (LC-qTOF-MS) has been developed for simultaneous determination of the aminoglycosides spectonomycin, tobramycin, gentamicin, kanamycin, hygromycin, apramycin, streptomycin, dihydrostreptomycin, amikacin and neomycin in milk and in bovine, poultry and swine muscles. A simple extraction method was developed using trichloroacetic acid and clean up with low temperature precipitation and C18 bulk. The LC–MS/MS and LC-qTOF-MS methods were validated according to the European Union Commission Directive 2002/657/EC. Adequate performance characteristics were obtained for recovery, precision, calibration curve, specificity, decision limits (CCα) and detection capabilities (CCβ) in all matrices tested. The detection limit (LOD) and limits of quantification (LOQ) was established from MRL ranging from 5 to 100 ng g-1 for LOD and 12.5 to 250 ng g-1 to LOQ. Recoveries ranged from 36.8 to 98.0% and the coefficient of variation from 0.9 to 20.2%, noting that all curves have been made into their own matrices in order to minimize the matrix effects which are intrinsic to the cases studied in this work. The CCβ values obtained in qualitative method were between 25 and 250 ng g-1, considered satisfactory for the analytes in those matrices. The proposed method proved to be simple, easy, and adequate for high-throughput analysis of a large number of samples per day at low cost.

A presença de compostos de uso veterinário em produtos de origem animal é uma grande preocupação em termos de saúde pública. A utilização descontrolada de antibióticos como medicamentos veterinários pode levar ao desenvolvimento de resistência bacteriana, podendo prejudicar a eficácia destas drogas no uso em humanos. Os aminoglicosídeos são antibióticos extensivamente utilizados na criação de animais para o tratamento de infecções bacterianas ou para a promoção do crescimento. A União Europeia estabeleceu níveis máximos de resíduos permitidos (LMRs) para os aminoglicosídeos em vários alimentos de origem animal. O governo brasileiro implementou um plano de controle que avalia os resíduos de medicamentos veterinários em produtos de origem animal. Neste trabalho, foram desenvolvidos método quantitativo por cromatografia a líquido acoplada a espectrometria de massas triplo quadrupolo em modo tandem (LC-MS/MS) e método de screening utilizando cromatografia a líquido acoplada a espectrometria de massas com analisador por tempo-de-voo (LC-qTOF-MS) para a determinação simultânea dos aminoglicosídeos espectinomicina, tobramicina, gentamicina, kanamicina, higromicina, apramicina, estreptomicina, diidroestreptomicina, amicacina e neomicina em leite e em músculo bovino, de aves e suíno. Como método de extração utilizou-se procedimento com ácido tricloroacético e clean up por precipitação a baixa temperatura e C18 a granel. Os métodos por LC-MS/MS e LC-qTOF-MS foram validados de acordo com a Diretiva da Comissão Europeia 2002/657/CE. Os resultados obtidos no método quantitativo para recuperação, precisão, linearidade, especificidade, limites de decisão (CCα) e capacidades de detecção (CCβ) nestas matrizes foram considerados satisfatórios. Os dados de limite de detecção (LOD) e limite de quantificação (LOQ) foram estabelecidos a partir dos LMRs, variando de 5 a 100 ng g-1 para LOD e 12,5 a 250 ng g-1 para LOQ. As recuperações variaram de 36,8 a 98%, e os coeficientes de variação ficaram entre 0,9 e 20,2%, observando-se que todas as curvas foram feitas com nas próprias matrizes a fim de minimizar os efeitos de matriz que são intrínsecos para os casos estudados neste trabalho. Os valores de CCβ obtidos no método qualitativo foram entre 25 e 250 ng g-1, considerados satisfatórios para os analitos nessas matrizes. O método proposto mostrou-se simples, fácil e adequado para a análise de um grande número de amostras por dia a um baixo custo. / The presence of several substances in animal products has been a major public concern. The use of antibiotics drugs as veterinary medicines might lead to the development of bacterial resistance, which might undermine the efficacy of these drugs in human use. The aminoglycosides are antibiotics that have been extensively employed in animal husbandry for the treatment of bacterial infections, but also as growth promotion. The European Union has issued strict maximum residue levels (MRLs) for aminoglycosides in several animal origin products. The Brazilian government implemented a control plan that assesses the residues of veterinary medicines in animal products. A quantitative method based on liquid chromatography tandem mass spectrometry (LC–MS/MS) and a screening method by liquid chromatography mass spectrometry with time-of-flight system (LC-qTOF-MS) has been developed for simultaneous determination of the aminoglycosides spectonomycin, tobramycin, gentamicin, kanamycin, hygromycin, apramycin, streptomycin, dihydrostreptomycin, amikacin and neomycin in milk and in bovine, poultry and swine muscles. A simple extraction method was developed using trichloroacetic acid and clean up with low temperature precipitation and C18 bulk. The LC–MS/MS and LC-qTOF-MS methods were validated according to the European Union Commission Directive 2002/657/EC. Adequate performance characteristics were obtained for recovery, precision, calibration curve, specificity, decision limits (CCα) and detection capabilities (CCβ) in all matrices tested. The detection limit (LOD) and limits of quantification (LOQ) was established from MRL ranging from 5 to 100 ng g-1 for LOD and 12.5 to 250 ng g-1 to LOQ. Recoveries ranged from 36.8 to 98.0% and the coefficient of variation from 0.9 to 20.2%, noting that all curves have been made into their own matrices in order to minimize the matrix effects which are intrinsic to the cases studied in this work. The CCβ values obtained in qualitative method were between 25 and 250 ng g-1, considered satisfactory for the analytes in those matrices. The proposed method proved to be simple, easy, and adequate for high-throughput analysis of a large number of samples per day at low cost.

A presença de compostos de uso veterinário em produtos de origem animal é uma grande preocupação em termos de saúde pública. A utilização descontrolada de antibióticos como medicamentos veterinários pode levar ao desenvolvimento de resistência bacteriana, podendo prejudicar a eficácia destas drogas no uso em humanos. Os aminoglicosídeos são antibióticos extensivamente utilizados na criação de animais para o tratamento de infecções bacterianas ou para a promoção do crescimento. A União Europeia estabeleceu níveis máximos de resíduos permitidos (LMRs) para os aminoglicosídeos em vários alimentos de origem animal. O governo brasileiro implementou um plano de controle que avalia os resíduos de medicamentos veterinários em produtos de origem animal. Neste trabalho, foram desenvolvidos método quantitativo por cromatografia a líquido acoplada a espectrometria de massas triplo quadrupolo em modo tandem (LC-MS/MS) e método de screening utilizando cromatografia a líquido acoplada a espectrometria de massas com analisador por tempo-de-voo (LC-qTOF-MS) para a determinação simultânea dos aminoglicosídeos espectinomicina, tobramicina, gentamicina, kanamicina, higromicina, apramicina, estreptomicina, diidroestreptomicina, amicacina e neomicina em leite e em músculo bovino, de aves e suíno. Como método de extração utilizou-se procedimento com ácido tricloroacético e clean up por precipitação a baixa temperatura e C18 a granel. Os métodos por LC-MS/MS e LC-qTOF-MS foram validados de acordo com a Diretiva da Comissão Europeia 2002/657/CE. Os resultados obtidos no método quantitativo para recuperação, precisão, linearidade, especificidade, limites de decisão (CCα) e capacidades de detecção (CCβ) nestas matrizes foram considerados satisfatórios. Os dados de limite de detecção (LOD) e limite de quantificação (LOQ) foram estabelecidos a partir dos LMRs, variando de 5 a 100 ng g-1 para LOD e 12,5 a 250 ng g-1 para LOQ. As recuperações variaram de 36,8 a 98%, e os coeficientes de variação ficaram entre 0,9 e 20,2%, observando-se que todas as curvas foram feitas com nas próprias matrizes a fim de minimizar os efeitos de matriz que são intrínsecos para os casos estudados neste trabalho. Os valores de CCβ obtidos no método qualitativo foram entre 25 e 250 ng g-1, considerados satisfatórios para os analitos nessas matrizes. O método proposto mostrou-se simples, fácil e adequado para a análise de um grande número de amostras por dia a um baixo custo. / The presence of several substances in animal products has been a major public concern. The use of antibiotics drugs as veterinary medicines might lead to the development of bacterial resistance, which might undermine the efficacy of these drugs in human use. The aminoglycosides are antibiotics that have been extensively employed in animal husbandry for the treatment of bacterial infections, but also as growth promotion. The European Union has issued strict maximum residue levels (MRLs) for aminoglycosides in several animal origin products. The Brazilian government implemented a control plan that assesses the residues of veterinary medicines in animal products. A quantitative method based on liquid chromatography tandem mass spectrometry (LC–MS/MS) and a screening method by liquid chromatography mass spectrometry with time-of-flight system (LC-qTOF-MS) has been developed for simultaneous determination of the aminoglycosides spectonomycin, tobramycin, gentamicin, kanamycin, hygromycin, apramycin, streptomycin, dihydrostreptomycin, amikacin and neomycin in milk and in bovine, poultry and swine muscles. A simple extraction method was developed using trichloroacetic acid and clean up with low temperature precipitation and C18 bulk. The LC–MS/MS and LC-qTOF-MS methods were validated according to the European Union Commission Directive 2002/657/EC. Adequate performance characteristics were obtained for recovery, precision, calibration curve, specificity, decision limits (CCα) and detection capabilities (CCβ) in all matrices tested. The detection limit (LOD) and limits of quantification (LOQ) was established from MRL ranging from 5 to 100 ng g-1 for LOD and 12.5 to 250 ng g-1 to LOQ. Recoveries ranged from 36.8 to 98.0% and the coefficient of variation from 0.9 to 20.2%, noting that all curves have been made into their own matrices in order to minimize the matrix effects which are intrinsic to the cases studied in this work. The CCβ values obtained in qualitative method were between 25 and 250 ng g-1, considered satisfactory for the analytes in those matrices. The proposed method proved to be simple, easy, and adequate for high-throughput analysis of a large number of samples per day at low cost.

The gut microbiota plays a major part in maintaining the health of a human host. Countless of crucial functions in the body, including immune responses, cell signaling and energy metabolism to name a few, are conducted by the gut microbiota and its metabolites. Accordingly, it is of interest to gain knowledge on what can alter the gut microbiota, as these alterations by extension can give rise to adverse health effects. In this study, the impact of polychlorinated biphenyl (PCB)- and organochlorine pesticide (OCP) exposure on tricarboxylic acid (TCA) cycle metabolites, short-chain fatty acids (SCFAs) and bile acids, as well as other polar and semi-polar metabolites, which are all related to the gut microbiota, were investigated. An in vitro fermentation of faecal samples exposed to a PCB/OCP mixture was performed, and liquid chromatography-time of flight mass spectrometry (LC-qToF-MS) targeted and non-targeted approaches were applied to the extracts. The results obtained suggested that PCBs and OCPs most likely have an effect on the levels of several features of the gut metabolome with either increased or decreased levels upon exposure. Bile acids and TCA metabolites appear to follow a trend of decreasing levels, while no apparent effects could be seen for the SCFAs. Furthermore, distinct concentrations of the PCB/OCP mixture appear to induce different changes in gut microbiota functioning, which highlights the importance of performing dose-response studies when exploring biological effects of these compounds. The identification of different metabolite profiles during fermentation also allows for the possibility of further investigation of potential biomarkers to assess PCB/OCP exposure.

京都大学 / 新制・課程博士 / 博士(工学) / 甲第24601号 / 工博第5107号 / 新制||工||1977(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 伊藤 禎彦, 准教授 西村 文武, 教授 越後 信哉 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

Polar organic compounds (POCs) are chemicals with polar functional groups in their structure. The functional groups make the compounds hydrophilic and less prone to partition with biota. However, the knowledge of their fate is limited due to difficulties associated with their measurements. Although, the persistence of POCs in the environment is generally low, they are considered to be semi-persistent compounds due to their continuous introduction to the environment via wastewater. Studies have shown that complex mixtures of POCs of different classes may have synergistic toxic effects on biota at environmental concentration levels. Therefore, it is important to develop analytical methods in order to establish the occurrence and fate of POCs in aquatic environments. In Study I, a positive correlation between the sorption of a novel poly(ethylene-co-vinyl acetate-co-carbon monoxide) (PEVAC) material and the theoretical logarithmic dissociation partition coefficient (Log D) for seven POCs was observed. The PEVAC material showed an enhanced sorption of the POCs compared to the silicone material. Study II, demonstrated that the PEVAC sampler assess the freely dissolved concentration of POCs in aquatic environments. The results showed that the PEVAC polymer is an attractive alternative to silicone for mimicing the biological uptake of POCs in aquatic environments. Additionally, Study II showed that total extraction is appropriate for determination of the freely dissolved concentration of uncharged POCs with Log KOW < 2.67 in natural water. In study III, a novel bag-solid phase extraction (bag-SPE) technique was compared to a conventional SPE-technique. Despite that the extraction efficiencies for POCs in wastewater were lower using the bag-SPE method, the two methods showed similar detection limits due to the lower ion-suppression experienced with the bag-SPE. In study IV the bag-SPE method was further developed with the aim of lowering the detection limits for POCs. Detection limits (LOD) below 13 ng/L showed that the bag-SPE method was suitable for determination of POCs in surface sea water. / This research was financially supported by European Union (European Commission, FP6 Contract No. 003956) “Novel Methods for Integrated Risk Assessment of Cumulative Stressors in the Environment” (NoMiracle) and by the Swedish research council Formas.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work presents multi-method for pesticide residues determination in fruit jams. Slurries of the fruit jams and ultrapure (u.p.) water were prepared to yield homogeneous samples and to facilitate the sample handling. The modified QuEChERS method was used for the sample preparation. Due the high detectability of the micro flow liquid chromatography triple quadrupole-linear ion trap mass spectrometry equipment (μLC-QTRAP-MS/MS) and to minimize the matrix effect (%) the acetonitrile extracts were diluted 30-fold before analysis. The method validation was performed analyzing spiked samples at the concentrations of 9 and 45 μg kg-1 (n=5). The method met validation criteria of 70 120% recovery and relative standard deviation (RSD) ≤ 20% for 93% (99) of the 107 pesticides evaluated. The reporting limit (RL) was 9 and 45 μg kg-1 for, respectively, 66% and 26% of the analytes, 5% of the compounds did not fulfill the requirements for validation and 3% were not detected at the studied concentrations. The validated method was applied to the analysis of 51 different fruit jam samples from Brazil and from Spain. Pesticide residues were detected in 80% of the samples, 51% of which contained at least one pesticide at concentration higher than 10 μg kg-1. Moreover, the stability of five pesticides was evaluated in the preparation of home-made fruit jams from spiked fruits. Thereunto, five types of fruits (orange, apple, strawberry, pear and peach, with n=2 for each type of fruit) were grinded and spiked at 500 μg kg-1 with a mixture of carbendazim, chlorpyrifos, imidacloprid, iprodione and propargite. Home-made jams were prepared with these spiked samples by cooking, over medium heat, the grinded spiked fruit with sugar and u.p. water (ratio, 5:5:2, w/w/w), in an open pan for 30 min. The modified QuEChERS extraction method was applied either to blank fruits, to the fruits spiked at 500 μg kg-1 and to the home-made jams (prepared from spiked fruits at 500 μg kg-1). The extracts of home-made jams and blank fruits were analyzed by liquid chromatography quadrupole-time of flight mass spectrometry (LC-QTOF-MS) to ascertain the occurrence of the known metabolites of the spiked pesticides and to determine the number of co-extracted matrix components from the fruits and from the jams. All samples were also analyzed by μLC-QTRAP-MS/MS for estimation of the pesticides processing factors. So the pesticide concentrations found in the spiked fruits were compared to the concentrations found in the home-made jams (pesticide concentration measured in the jams/pesticide concentration measured in the raw fruits). / Este trabalho apresenta um método multirresidual para determinação de resíduos de agrotóxicos em doces de fruta em pasta. Para obter-se amostras homogêneas e de fácil manipulação preparou-se uma mistura (slurry) dos doces de frutas e água ultrapura (u.p.). O preparo das amostras foi feito utilizando o método QuEChERS modificado. Com o objetivo de diminuir o efeito matriz (%) das amostras e pela alta detectabilidade do equipamento de cromatografia de micro vazão a líquido acoplada à espectrometria de massas híbrida triplo quadrupolo-armadilha de íons linear (μLC-QTRAP-MS/MS) os extratos de acetonitrila foram diluídos na razão de 1:30 (v/v) antes da análise. A validação do método analítico foi feita pela análise de amostras de doces de uva fortificadas nas concentrações de 9 e 45 μg kg-1 (n=5). Dos 107 agrotóxicos avaliados 93% (99) obtiveram recuperações de 70 a 120% e desvio padrão relativo (RSD) ≤ 20%. Os limites de notificação (RL) foram de 9 e 45 μg kg-1 para, respectivamente, 66% e 26% dos agrotóxicos avaliados, 5% dos compostos não alcançaram os pré-requisitos necessários para a validação e 3% não foram detectados nas concentrações estudadas. Após a validação do método, foram analisadas 51 amostras de doces de frutas provenientes do Brasil e da Espanha. Em 80% amostras foram detectados resíduos de agrotóxicos, 51% destas continham no mínimo um agrotóxico em concentração maior que 10 μg kg-1. Além disso, avaliou-se a estabilidade de cinco agrotóxicos no preparo de doces de frutas caseiros. Para isso, cinco tipos de frutas (laranja, maçã, morango, pera e pêssego, com n=2 para cada tipo de fruta) foram trituradas e fortificadas com uma mistura de carbendazim, clorpirifós, imidacloprido, iprodiona e propargito a 500 μg kg-1. Essas amostras foram utilizadas no preparo de doces de frutas caseiros. Para isso, as frutas trituradas e fortificadas foram cozidas com açúcar e água u.p. (proporção de 5:5:2, m/m/m) em panela aberta sob fogo médio durante 30 min. O método QuEChERS modificado foi aplicado às frutas não fortificadas, às frutas fortificadas (500 μg kg-1) e aos doces de frutas caseiros (preparados com frutas fortificadas a 500 μg kg-1). Os extratos dessas amostras foram analisados por cromatografia a líquido acoplada à espectrometria de massas híbrida quadrupolo-de tempo de voo (LC-QTOF-MS), com o objetivo de verificar a presença dos metabólitos conhecidos dos agrotóxicos e determinar o número de componentes coextraídos das matrizes. Todas as amostras foram analisadas também por μLC-QTRAPMS/ MS com o objetivo de comparar a concentração dos agrotóxicos nas frutas fortificadas com as concentrações nos doces de frutas correspondentes. A partir dessa relação foi possível estimar um fator de processamento (FP) para os agrotóxicos no preparo dos doces de frutas caseiros (concentração do agrotóxico no doce de fruta/concentração do agrotóxico na fruta fortificada).