Resumo
A cetamina é um anestésico amplamente difundido, principalmente em medicina veterinária. Devido a seu efeito dissociativo, indução à amnésia e a efeitos psicodélicos é frequentemente utilizada como droga de abuso e como droga facilitadora para práticas criminosas, dentre as quais o chamado golpe boa noite Cinderela. Entretanto, esse tipo de crime é de difícil comprovação, pois, necessita de perícia imediata e metodologias analíticas sensíveis, validadas de acordo com o tipo de matriz biológica em exame. O cabelo tem se mostrado uma matriz importante na investigação criminal por conta da ampla janela de detecção, maior que a de outras matrizes biológicas; além disso, é possível realizar a análise multissecional, que distingue o uso recreacional frequente do uso criminoso, usualmente realizado com dose única, capaz de incapacitar uma vítima. A cromatografia líquida acoplada à espectrometria de massas sequencial (CLEM/ EM) vem sendo muito empregada na área forense devido a sua especificidade e sensibilidade. No presente estudo foi desenvolvida uma metodologia para determinação da cetamina e norcetamina em cabelo por CL-EM/EM em amostras de cabelo pulverizado, empregando a extração das amostras por tampão e purificação por extração em fase sólida com fase mista polimérica/troca catiônica. O desenvolvimento incluiu uma etapa de produção de amostras fortificadas por incorporação do analito no cabelo, onde diferentes métodos de incorporação foram testados. A escolha do meio, do processo mecânico de extração e testes com diferentes tipos de pré-tratamento do cabelo - picotamento e dois graus de moagem foram feitos com as amostras fortificadas por incorporação. A validação realizada mostrou que o método possui linearidade na faixa de 0,02 10 ng mg-1 para cetamina e 0,04 4 ng mg-1 para norcetamina. Os parâmetros de exatidão, precisão, efeito matriz e recuperação ficaram dentro dos limites de aceitação principalmente segundo a ANVISA e SWGTOX. A metodologia validada foi aplicada a amostras autênticas (n=3) de indivíduos que receberam dose única de cetamina como medicação anestésica. A análise do segmento de cabelo que corresponde à época em que o medicamento foi aplicado demonstrou a presença do fármaco nas amostras.
Ketamine is a widespread anesthetic, especially in veterinary medicine. Due to its dissociative effect, inducing amnesia and psychedelic effects, it is often used as a drug of abuse and as a facilitator for drug facilitated crimes, among which the best known is the so-called in Brazil "Ketamine is a widespread anesthetic, especially in veterinary medicine. Due to its dissociative effect, inducing amnesia and psychedelic effects, it is often used as a drug of abuse and as a facilitator for drug facilitated crimes, among which the best known is the so-called in Brazil "good night Cinderella blow, also known as date rape crime. However, this kind of crime is difficult to prove because it requires immediate forensic investigation, by different sensitive, validated analytical methodologies, according to the type of biological matrix in examination. Hair is an important matrix in criminal investigation because of its wide detection window, larger than that of other biological matrices. Furthermore, with hair it is possible to perform multi-sectional analysis, which distinguishes frequent recreational from criminal use, normally done with a single dose capable of incapacitating a victim. Liquid chromatography coupled to tandem mass spectrometry (LC-MS / MS) has been widely used in forensics because of its specificity and sensitivity. In this study we developed a methodology for determination of ketamine and norketamine in hair by LC-MS/MS in pulverized hair samples, using a buffer for extraction and solid phase extraction (SPE) as a clean-up step. The development of the method included the production of fortified samples, by incorporation of the analyte into hair. The choice of extraction medium and of mechanical assistance (vortex or ultrassonic bath) was performed with samples fortified by incorporation. The effect of sample pretreatment hair cutting or pulverization at two different levels on the amount of analyte extracted was also investigated. The validation performed showed that the method was linear in the range of 0.02 to 10 ng-mg-1 for ketamine and 0.04 to 4 ng mg-1 for norketamine. Accuracy, precision, and matrix effects were within the acceptance limits mainly according to ANVISA and SWGTOX. The validated methodology was applied to authentic samples (n = 3) from subjects who received a single dose of ketamine as an anesthetic medication. The analysis of the hair segment that corresponds to the time when the drug was applied demonstrated the drug presence in the samples. blow, also known as date rape crime. However, this kind of crime is difficult to prove because it requires immediate forensic investigation, by different sensitive, validated analytical methodologies, according to the type of biological matrix in examination. Hair is an important matrix in criminal investigation because of its wide detection window, larger than that of other biological matrices. Furthermore, with hair it is possible to perform multi-sectional analysis, which distinguishes frequent recreational from criminal use, normally done with a single dose capable of incapacitating a victim. Liquid chromatography coupled to tandem mass spectrometry (LC-MS / MS) has been widely used in forensics because of its specificity and sensitivity. In this study we developed a methodology for determination of ketamine and norketamine in hair by LC-MS/MS in pulverized hair samples, using a buffer for extraction and solid phase extraction (SPE) as a clean-up step. The development of the method included the production of fortified samples, by incorporation of the analyte into hair. The choice of extraction medium and of mechanical assistance (vortex or ultrassonic bath) was performed with samples fortified by incorporation. The effect of sample pretreatment hair cutting or pulverization at two different levels on the amount of analyte extracted was also investigated. The validation performed showed that the method was linear in the range of 0.02 to 10 ng-mg-1 for ketamine and 0.04 to 4 ng mg-1 for norketamine. Accuracy, precision, and matrix effects were within the acceptance limits mainly according to ANVISA and SWGTOX. The validated methodology was applied to authentic samples (n = 3) from subjects who received a single dose of ketamine as an anesthetic medication. The analysis of the hair segment that corresponds to the time when the drug was applied demonstrated the drug presence in the samples.