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1.
Subst Use Misuse ; 59(6): 867-873, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38270342

RESUMEN

PURPOSE: Computerized adaptive tests (CATs) are highly efficient assessment tools that couple low patient and clinician time burden with high diagnostic accuracy. A CAT for substance use disorders (CAT-SUD-E) has been validated in adult populations but has yet to be tested in adolescents. The purpose of this study was to perform initial evaluation of the K-CAT-SUD-E (i.e., Kiddy-CAT-SUD-E) in an adolescent sample compared to a gold-standard diagnostic interview. METHODS: Adolescents (N = 156; aged 11-17) with diverse substance use histories completed the K-CAT-SUD-E electronically and the substance related disorders portion of a clinician-conducted diagnostic interview (K-SADS) via tele-videoconferencing platform. The K-CAT-SUD-E assessed both current and lifetime overall SUD and substance-specific diagnoses for nine substance classes. RESULTS: Using the K-CAT-SUD-E continuous severity score and diagnoses to predict the presence of any K-SADS SUD diagnosis, the classification accuracy ranged from excellent for current SUD (AUC = 0.89, 95% CI = 0.81, 0.95) to outstanding (AUC = 0.93, 95% CI = 0.82, 0.97) for lifetime SUD. Regarding current substance-specific diagnoses, the classification accuracy was excellent for alcohol (AUC = 0.82), cannabis (AUC = 0.83) and nicotine/tobacco (AUC = 0.90). For lifetime substance-specific diagnoses, the classification accuracy ranged from excellent (e.g., opioids, AUC = 0.84) to outstanding (e.g., stimulants, AUC = 0.96). K-CAT-SUD-E median completion time was 4 min 22 s compared to 45 min for the K-SADS. CONCLUSIONS: This study provides initial support for the K-CAT-SUD-E as a feasible accurate diagnostic tool for assessing SUDs in adolescents. Future studies should further validate the K-CAT-SUD-E in a larger sample of adolescents and examine its acceptability, feasibility, and scalability in youth-serving settings.


Asunto(s)
Cannabis , Trastornos Relacionados con Sustancias , Adulto , Humanos , Adolescente , Trastornos Relacionados con Sustancias/diagnóstico , Etanol , Escalas de Valoración Psiquiátrica
2.
Alcohol Clin Exp Res ; 43(11): 2446-2457, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31524960

RESUMEN

BACKGROUND: Cannabinoids and their principle psychoactive target, the cannabinoid type 1 receptor (CB1R), impact a number of alcohol-related properties, and although alcohol and cannabis are often co-used, particularly in adolescence, few animal models of this phenomenon exist. We modeled the co-use of alcohol and ∆9 -tetrahydrocannabinol (THC) in adolescent mice using ingestive methods popular during this developmental period in humans, namely binge-drinking and edible THC. With this model, we assessed levels of use, acute effects, and tolerance to each substance. METHODS: Adolescent male C57BL/6J mice had daily, limited access to 1 of 2 edible doughs (THC or control), to 1 of 2 fluids (ethanol (EtOH) or water), and in 1 of 2 orders (dough-fluid or fluid-dough). Home cage locomotor activity was recorded both during access and after access. On the day following the final access session, a subset of mice were assessed for functional and metabolic tolerance to alcohol using accelerating rotarod and blood EtOH concentrations, respectively. The remaining mice were assessed for tolerance to THC-induced hypothermia, and whole-brain CB1R expression was assessed in all mice. RESULTS: EtOH intake was on par with levels previously reported in adolescent mice. Edible THC was well-consumed, but consumption decreased at the highest dose provided. Locomotor activity increased following EtOH intake and decreased following edible THC consumption, and edible THC increased fluid intake in general. The use of alcohol produced neither functional nor metabolic tolerance to an alcohol challenge. However, the use of edible THC impaired subsequent drug-free rotarod performance and was associated with a reduction in THC's hypothermic effect. CONCLUSIONS: Adolescent mice self-administered both alcohol and edible THC to a degree sufficient to acutely impact locomotor activity. However, only edible THC consumption had lasting effects during short-term abstinence. Thus, this adolescent co-use model could be used to explore sex differences in self-administration and the impact substance co-use might have on other domains such as mood and cognition.


Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Dronabinol/administración & dosificación , Abuso de Marihuana/complicaciones , Actividad Motora/efectos de los fármacos , Animales , Modelos Animales de Enfermedad , Interacciones Farmacológicas , Tolerancia a Medicamentos , Masculino , Ratones , Ratones Endogámicos C57BL , Autoadministración
3.
Cogn Affect Behav Neurosci ; 17(2): 235-251, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28000083

RESUMEN

Increasing evidence supports the hypothesis that impulsive decision-making is a heritable risk factor for an alcohol use disorder (AUD). Clearly identifying a link between impulsivity and AUD risk, however, is complicated by the fact that both AUDs and impulsivity are heterogeneous constructs. Understanding the link between the two requires identifying the underlying cognitive factors that lead to impulsive choices. Rodent models have established that a family history of excessive drinking can lead to the expression of a transgenerational impulsive phenotype, suggesting heritable alterations in the decision-making process. In the present study, we explored the cognitive processes underlying impulsive choice in a validated, selectively bred rodent model of excessive drinking-the alcohol-preferring ("P") rat. Impulsivity was measured via delay discounting (DD), and P rats exhibited an impulsive phenotype as compared to their outbred foundation strain-Wistar rats. Steeper discounting in P rats was associated with a lack of a prospective behavioral strategy, which was observed in Wistar rats and was directly related to DD. To further explore the underlying cognitive factors mediating these observations, a drift diffusion model of DD was constructed. These simulations supported the hypothesis that prospective memory of the delayed reward guided choice decisions, slowed discounting, and optimized the fit of the model to the experimental data. Collectively, these data suggest that a deficit in forming or maintaining a prospective behavioral plan is a critical intermediary to delaying reward, and by extension, may underlie the inability to delay reward in those with increased AUD risk.


Asunto(s)
Consumo de Bebidas Alcohólicas/psicología , Alcoholismo/psicología , Descuento por Demora , Conducta Impulsiva , Memoria Episódica , Consumo de Bebidas Alcohólicas/genética , Alcoholismo/genética , Animales , Simulación por Computador , Condicionamiento Operante , Modelos Animales de Enfermedad , Función Ejecutiva , Predisposición Genética a la Enfermedad , Habituación Psicofisiológica , Masculino , Modelos Psicológicos , Actividad Motora , Fenotipo , Ratas Wistar , Tiempo de Reacción , Especificidad de la Especie
4.
Alcohol Clin Exp Res ; 40(6): 1351-60, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27154344

RESUMEN

BACKGROUND: Binge co-consumption of highly caffeinated energy drinks with alcohol (ethanol [EtOH]) has become a common practice among adolescents/young adults and has been associated with an increased incidence of hazardous behaviors. Animal models are critical in advancing our understanding the neurobehavioral consequences of this form of binge drinking. Surprisingly, virtually no work has explored caffeine and EtOH co-consumption or its long-term consequences in adolescent animals. The primary objective of the current study was to extend a previously established mouse model of voluntary binge caffeine and EtOH co-consumption to explore adolescent consumption and responses compared to adults. METHODS: Adolescent and adult male C57BL/6J mice had daily limited access to caffeine (0.03% w/v), EtOH (20% v/v), a combined EtOH/caffeine solution, or water for 14 days via the binge-like drinking paradigm, drinking-in-the-dark (DID). Home cage locomotor activity was measured during DID in a subset of mice. Following DID, all mice rested for 18 days so that adolescents reached adulthood, whereupon all mice underwent 7 days of continuous access 2-bottle choice drinking for 10% (v/v) EtOH or water. RESULTS: Co-consumption with caffeine significantly increased EtOH intake and resultant blood ethanol concentrations in both adolescent and adult mice. In addition, adolescent mice exhibited a uniquely robust locomotor stimulant response to caffeine and EtOH co-consumption. Later EtOH intake and preference was not influenced, however, by prior fluid consumption history via DID. CONCLUSIONS: Together with findings from the human literature, our results suggest that caffeine co-consumption may positively influence binge alcohol consumption in adolescents/young adults. Importantly, this age group may be particularly sensitive to the additive stimulant effects of caffeinated alcohol consumption, an effect which may be related to the high incidence of associated negative outcomes in this population. These observations are particularly concerning considering the heightened plasticity of the adolescent brain.


Asunto(s)
Consumo Excesivo de Bebidas Alcohólicas/psicología , Cafeína/farmacología , Etanol/farmacología , Factores de Edad , Animales , Modelos Animales de Enfermedad , Sinergismo Farmacológico , Masculino , Ratones , Actividad Motora/efectos de los fármacos
5.
Psychiatr Serv ; 75(10): 979-985, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38835252

RESUMEN

OBJECTIVE: The authors examined the initial implementation of the Indiana Adolescent Addiction Access (AAA) program, modeled on the widely disseminated Child Psychiatry Access Program framework. The AAA program developed a statewide consultation helpline to connect health care providers with adolescent addiction specialists. METHODS: The AAA line was staffed by a coordinator, who fielded initial questions, and on-call clinical specialists (social workers, nurse practitioners, psychiatrists, and psychologists), who were paged to complete telephone consultations and provide care recommendations. When necessary, AAA providers offered urgent clinical assessments and initiated treatment. Descriptive analyses were performed for key variables over the first 21 months of AAA operations. RESULTS: From July 2021 to March 2023, a total of 125 consultations were completed. Most callers were health care providers (71%) or parents (27%). Calls pertained to youths ages 10-18 years (mean±SD age=16.4±1.3; 62% of callers were male, 84% White, and 11% Black), with concerns around cannabis (63%), opioids (38%), and other substances. About 26% of calls related to an overdose, and 41% of cases were rated as severe. Recommendations included starting new medications (17%) or outpatient therapy (86%), and 17% of consultations resulted in urgent evaluations. CONCLUSIONS: The Indiana AAA program helps overcome key barriers to adolescent substance use treatment. Increasing the capacity to initiate medication for opioid use disorder and other treatment rapidly through consultation and direct care is a promising, scalable approach for preventing overdose deaths among youths.


Asunto(s)
Líneas Directas , Trastornos Relacionados con Opioides , Derivación y Consulta , Humanos , Adolescente , Indiana , Masculino , Líneas Directas/estadística & datos numéricos , Femenino , Niño , Trastornos Relacionados con Opioides/terapia , Trastornos Relacionados con Opioides/tratamiento farmacológico , Trastornos Relacionados con Sustancias/terapia , Accesibilidad a los Servicios de Salud , Servicios de Salud del Adolescente
6.
J Behav Health Serv Res ; 50(3): 333-347, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36859743

RESUMEN

A significant gap remains in the availability and accessibility of evidence-based treatments (EBTs) in community substance use disorder (SUD) treatment. This study describes a 2-year statewide training initiative that sought to address this gap by training community-based therapists in motivational enhancement/cognitive behavioral therapy (MET/CBT). Therapists (N = 93) participated in a 2-day MET/CBT workshop followed by bi-weekly clinical consultation, fidelity monitoring, guided readings, and online resources. Therapists completed pre-training and follow-up assessments measuring knowledge, attitudes, confidence, and implementation barriers. Most therapists attended 10 or more consultation calls. Submission of session recordings for feedback was the least utilized training element. Therapists reported increased confidence in their ability to implement MET/CBT for SUD and demonstrated improvement in MI and CBT knowledge. Therapists reported several implementation barriers, including lack of time and opportunity to treat patients with MET/CBT. Recommendations for future training initiatives and addressing the barriers identified in this study are discussed.


Asunto(s)
Terapia Cognitivo-Conductual , Trastornos Relacionados con Sustancias , Humanos , Terapia Cognitivo-Conductual/educación , Salud Mental , Resultado del Tratamiento , Actitud , Trastornos Relacionados con Sustancias/terapia , Trastornos Relacionados con Sustancias/psicología
7.
Drug Alcohol Depend Rep ; 3: 100047, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36845991

RESUMEN

Introduction: The Computerized Adaptive Test for Substance Use Disorder (CAT-SUD), an adaptive test based on multidimensional item response theory, has been expanded to include 7 specific Diagnostic and Statistical Manual, 5th edition (DSM-5) defined SUDs. Initial testing of the new measure, the CAT-SUD expanded (CAT-SUD-E) is reported here. Methods: 275 Community-dwelling adults (ages 18-68) responded to public and social-media advertisements. Participants virtually completed both the CAT-SUD-E and the Structured Clinical Interview for DSM-5, Research Version (SCID) to assess the validity of the CAT-SUD-E in determining whether participants met criteria for specific DSM-5 SUDs. Diagnostic classifications were based on 7 SUDs, each with 5 items, for current and lifetime SUDs. Results: For SCID-based presence of any lifetime SUD, predictions based on the overall CAT-SUD-E diagnosis and severity score were AUC=0.92, 95% CI = 0.88, 0.95 for current and AUC=0.94, 95% CI = 0.91, 0.97 for lifetime. For individual diagnoses, classification accuracy for current SUDs ranged from an AUC=0.76 for alcohol to AUC=0.92 for nicotine/tobacco. Classification accuracy for lifetime SUDs ranged from an AUC=0.81 for hallucinogens to AUC=0.96 for stimulants. Median CAT-SUD-E completion time was under 4 min. Conclusions: The CAT-SUD-E quickly produces similar results as lengthy structured clinical interviews for overall SUD and substance-specific SUDs, with high precision and accuracy, through a combination of fixed-item responses for diagnostic classification and adaptive SUD severity measurement. The CAT-SUD-E harmonizes information from mental health, trauma, social support and traditional SUD items to provide a more complete characterization of SUD and provides both diagnostic classification and severity measurement.

8.
Drug Alcohol Depend ; 199: 106-115, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-31029878

RESUMEN

BACKGROUND: With increasing access to legal cannabis across the globe, it is imperative to more closely study its behavioral and physiological effects. Furthermore, with the proliferation of cannabis use, modes of consumption are changing, with edible formulations becoming increasingly popular. Nevertheless, there are relatively few animal models of self-administration of the primary psychoactive component of cannabis, Δ9-tetrahydrocannabinol (THC), and almost all incorporate routes of administration other than those used by humans. The aim of the current study was to develop a model of edible THC self-administration and assess its impact on CB1 receptor-mediated behaviors in female and male mice. METHODS: Mice were given limited access to a palatable dough which occasionally contained THC in doses ranging from 1 to 10 mg/kg. Following dough consumption, mice were assessed for home cage locomotor activity, body temperature, or analgesia. Locomotor activity was also assessed in conjunction with the CB1 receptor antagonist SR141716A. RESULTS: Dough was well-consumed, but consumption decreased at the highest THC concentrations. Edible THC produced dose-dependent decreases in locomotor activity and body temperature in both sexes, and these effects were more pronounced in male mice. Hypolocomotion induced by edible THC was attenuated by SR141716A, indicating mediation by CB1 receptor activation. CONCLUSIONS: In contrast to other cannabinoid self-administration models, edible THC is relatively low in stress and uses a route of administration analogous to one used by humans. Potential applications include chronic THC self-administration, determining THC reward/reinforcement, and investigating consequences of oral THC use.


Asunto(s)
Temperatura Corporal/efectos de los fármacos , Dronabinol/administración & dosificación , Actividad Motora/efectos de los fármacos , Psicotrópicos/administración & dosificación , Recompensa , Animales , Temperatura Corporal/fisiología , Cannabinoides/administración & dosificación , Relación Dosis-Respuesta a Droga , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Actividad Motora/fisiología , Receptor Cannabinoide CB1/agonistas , Receptor Cannabinoide CB1/antagonistas & inhibidores , Receptor Cannabinoide CB1/fisiología , Autoadministración
9.
J Agric Food Chem ; 63(43): 9657-65, 2015 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-26473587

RESUMEN

A method for the determination of 35 acid herbicides in food matrices was developed, validated, and implemented. It utilizes a modified QuEChERS extraction procedure coupled with quantitation by liquid chromatography tandem mass spectrometry (LC-MS/MS). The acid herbicides analyzed are all organic carboxylic acids, including the older chlorophenoxy acid herbicides such as 2,4-dichlorophenoxyacetic acid (2,4-D), dicamba, 4-chlorophenoxyacetic acid (4-CPA), quinclorac, and many of the newer imidazolinone herbicides such as imazethapyr and imazaquin. In the procedure, 10 mL of water is added to 5 g of sample and then extracted with 1% formic acid in acetonitrile for 1 min. The acetonitrile phase is salted out of the extract by adding sodium chloride and magnesium sulfate, followed by centrifugation. The acetonitrile is diluted 1:1 with water to enable quantitation by LC-MS/MS using fast switching between positive and negative electrospray ionization modes. The average recoveries for all the compounds except aminocyclopyrachlor were 95% with a precision of 8%. The method detection limits for all residues were less than 10 ng/g, and the correlation coefficients for the calibration curves was greater than 0.99 for all but two compounds tested. The method was used successfully for the quantitation of acid herbicides in the FDA's total diet study. The procedure proved to be accurate, precise, linear, sensitive, and rugged.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Herbicidas/química , Herbicidas/aislamiento & purificación , Residuos de Plaguicidas/química , Residuos de Plaguicidas/aislamiento & purificación , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos , Contaminación de Alimentos/análisis
10.
Psychopharmacology (Berl) ; 232(3): 551-60, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25038869

RESUMEN

RATIONALE: Nicotine and ethanol are commonly coabused drugs, and nicotine-laced ethanol products are growing in popularity. However, little is known about time-course changes in extracellular nicotine and cotinine levels in rat models of ethanol and nicotine coabuse. OBJECTIVES: The objective of the present study was to determine the time-course changes in brain levels of nicotine and cotinine following subcutaneous (SC) and intragastric (IG) nicotine administration in alcohol-preferring (P) and Wistar rats. METHODS: In vivo microdialysis was used to collect dialysate samples from the nucleus accumbens shell (NACsh) for nicotine and cotinine determinations, following SC administration of (-)-nicotine (0.18, 0.35, and 0.70 mg/kg) in female P and Wistar rats or IG administration of (-)-nicotine (0.35 and 0.70 mg/kg) in 15 % (v/v) ethanol or water in female P rats. RESULTS: SC nicotine produced nicotine and cotinine dialysate levels as high as 51 and 14 ng/ml, respectively. IG administration of 15 % EtOH + 0.70 mg/kg nicotine in P rats resulted in maximal nicotine and cotinine dialysate levels of 19 and 14 ng/ml, respectively, whereas administration of 0.70 mg/kg nicotine in water resulted in maximal nicotine and cotinine levels of 21 and 25 ng/ml, respectively. Nicotine and cotinine levels were detectable within the first 15 and 45 min, respectively, after IG administration. CONCLUSIONS: Overall, the results of this study suggest that nicotine is rapidly adsorbed and produces relevant extracellular brain concentrations of nicotine and its pharmacologically active metabolite, cotinine. The persisting high brain concentrations of cotinine may contribute to nicotine addiction.


Asunto(s)
Alcoholismo/metabolismo , Encéfalo/efectos de los fármacos , Cotinina/farmacocinética , Etanol/farmacocinética , Nicotina/farmacocinética , Tabaquismo/metabolismo , Animales , Modelos Animales de Enfermedad , Etanol/administración & dosificación , Femenino , Nicotina/administración & dosificación , Núcleo Accumbens/efectos de los fármacos , Ratas , Ratas Wistar
11.
J Agric Food Chem ; 59(12): 6383-411, 2011 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-21520933

RESUMEN

Seven FDA pesticide laboratories collaborated to develop and validate an LC-MS/MS method to determine 173 pesticides in <20 min. The average determination coefficient (r²) was >0.99 for all but two compounds tested. The limits of detection were <20 ng/mL for all compounds and <10 ng/mL for 363 of the 368 transitions reported. The method was used to determine pesticides in two AOAC sponsored proficiency samples. The LC-MS/MS determination was used for the analysis of oranges, carrots and spinach using the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, Safe) method. Each matrix was fortified at 20, 100, 400, and 1000 ng/g. No false positive responses were detected in controls of the three matrices. 165 pesticides had recoveries between 70 and 130%, and 161 had minimum detection levels less than 10 ng/g. Recoveries of 169 compounds for the 1000 ng/g spikes were within 50-150%. A matrix effect study indicated all three matrices caused a small net suppressing effect, the most pronounced attributable to the citrus matrix. The procedure proved to be accurate, precise, linear, sensitive and rugged, and adds 100 pesticides to the scope of the FDA pesticide program.


Asunto(s)
Cromatografía Liquida/métodos , Contaminación de Alimentos/análisis , Frutas/química , Residuos de Plaguicidas/análisis , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos , Verduras/química , Residuos de Plaguicidas/aislamiento & purificación
12.
J Agric Food Chem ; 59(14): 7636-46, 2011 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-21671617

RESUMEN

A multiresidue method analyzing 209 pesticides in 24 agricultural commodities has been developed and validated using the original Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) procedure and high performance liquid chromatography-positive electrospray ionization-tandem mass spectrometry (LC-MS/MS) analysis. Using solvent-only calibration standards (SOCSs) and matrix-matched calibration standards (MMCSs), it was demonstrated that a minimal concentration of 5-10 µg/kg (part per billion, ppb) of analytes in matrix is required for the consistent identification of targeted pesticides with two MRM transitions. Method performance was validated by the precision and accuracy results obtained from fortification studies at 10, 25, 100, and 500 ppb and MMCSs. The method was demonstrated to achieve an average recovery of 100 ± 20% (n = 4) for >75% of evaluated pesticides at the low fortification level (10 ppb) and improved to >84% at the higher fortification concentrations in all 24 matrices. Matrix effects in LC-MS/MS analysis were studied by evaluating the slope ratios of calibration curves (1.0-100 ng/mL) obtained from the SOCSs and MMCSs. Principal component analysis (PCA) of LC-MS/MS and method validation data confirmed that each matrix exerts its specific effect during the sample preparation and LC-MS/MS analysis. The matrix effect is primarily dependent on the matrix type, pesticide type and concentration. Some caution is warranted when using matrix matched calibration curves for the quantitation of pesticides to alleviate concerns on matrix effects. The QuEChERS method with LC-MS/MS was used to identify and quantitate pesticides residues, with concentrations ranging from 2.5 to >1000 ppb in a variety of agricultural samples, demonstrating fitness for screening and surveillance applications.


Asunto(s)
Fraccionamiento Químico/métodos , Cromatografía Líquida de Alta Presión/métodos , Productos Agrícolas/química , Residuos de Plaguicidas/análisis , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos , Acetonitrilos , Frutas/química , Residuos de Plaguicidas/aislamiento & purificación , Verduras/química
13.
J Agric Food Chem ; 58(23): 12101-4, 2010 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-21062062

RESUMEN

A simple and rapid method for determining polycyclic aromatic hydrocarbons (PAHs) in shrimp is described. For sample preparation, the quick and simple QuEChERS procedure was used. Reverse-phase chromatography using an octadecyl silica (C18) column and water/acetonitrile gradient elution was used to separate analyte mixtures. After separation, PAHs were detected using liquid chromatography-tandem mass spectrometry (LC-MS/MS) equipped with the atmospheric pressure photoionization (PhotoSpray APPI) source operating in the positive-ion mode. In this methodology, all 16 common PAHs were used and toluene served as a charged dopant to efficiently ionize analyte molecules through secondary reactions. Spikes were performed at 0.2 and 1 µg/g with and without primary and secondary amine (PSA) sorbent cleanup. Recoveries of PAHs were good, with ion ratios that agreed well between the spikes and standards. Without cleanup at 0.2 µg/mL, seven compounds had relatively low recovery (49-69%) and one compound, naphthalene, had a somewhat high recovery of 129%. At 1 µg/mL without cleanup, only three compounds had slightly lower recovery (66-67%). When PSA cleanup was performed, all PAH recoveries were within 75-125% at both spike levels.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Crustáceos/química , Contaminación de Alimentos/análisis , Hidrocarburos Policíclicos Aromáticos/química , Mariscos/análisis , Espectrometría de Masas en Tándem/métodos , Animales , Cromatografía de Fase Inversa/métodos
14.
J Agric Food Chem ; 58(10): 5897-903, 2010 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-20196606

RESUMEN

A high-throughput, QuEChERS (Quick, Easy, Cheap, Effective, Rugged, Safe) sample preparation and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analytical method has been developed and validated for the determination of 191 pesticides in vegetation and fruit samples. Using identical LC analytical column and MS/MS instrumentation and operation parameters, this method was evaluated at the U.S. Food and Drug Administration (FDA), National Research Centre for Grapes (NRCG), India, and Ontario Ministry of the Environment (MOE) laboratories. Method validation results showed that all but 1 of these 191 pesticides can be analyzed by LC-MS/MS with instrument detection limits (IDL) in the parts per trillion (ppt) range. Matrix-dependent IDL studies showed that due to either the low ionization efficiency or matrix effect exerted, 14 of these 191 pesticides could not be analyzed by this method. Method recovery (%R) and method detection limits (MDLs) were determined by the three laboratories using four sample matrices in replicates (N = 4). With >79% of %R data from the fortification studies in the range from 80 to 120%, MDLs were determined in the low parts per billion range with >94% of MDLs in the range from 0.5 to 5 ppb. Applying this method to the analysis of incurred samples showed that two multiple reaction monitoring (MRM) transitions may not be enough to provide 100% true positive identification of target pesticides; however, quantitative results obtained from the three laboratories had an excellent match with only a few discrepancies in the low parts per billion levels. The %R data from the fortification studies were subjected to principal component analysis and showed the majority of %R fell into the cluster of 80% < %R < 120%. Due to the matrix effect exerted by ginseng and peach, outliers were observed at the lowest spiking levels of 10 and 25 ppb. The study also showed that QuEChERS samples should be analyzed as soon as prepared or stored in a freezer to avoid any adverse affect on the analytes evaluated.


Asunto(s)
Fraccionamiento Químico/métodos , Cromatografía Liquida/métodos , Residuos de Plaguicidas/análisis , Espectrometría de Masas en Tándem/métodos , Citrus sinensis/química , Frutas/química , Laboratorios , Panax/química , Extractos Vegetales/química , Prunus/química , Control de Calidad , Spinacia oleracea/química , Verduras/química
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