No abstract

An essential oil from Senecio atacamensis Phil. (Asteraceae) was obtained by hydrodistillation of its aerial parts (leaves and stems) and its composition was determined by GC and GC/MS analysis. The identification by GC of the essential oil components, in both leaves and stems respectively, showed α-terpinene (36.05% and 20.57%); α-phellandrene (27.79% and 25.37%), and p-cymene (11.85% and 22.55%) as the most abundant monoterpenes. Furthermore, the oil was tested for its antimicrobial activity using paper disc diffusion and the dilution broth method, exhibiting moderate inhibition of human pathogenic bacteria.

Four benzodiazepines flunitrazepam, nitrazepam, clonazepam, and alprazolam, have been analyzed from biological matrices by dual column gas chromatography using a nitrogen-phosphorus detector (NPD) and a micro-electron capture detector (m-ECD). The recoveries of the four benzodiazepines spiked into human whole blood and plasma were 88.8 -97.9 and 90.7 -97.5%, respectively. The regression equations for the four benzodiazepines showed excellent linearity. The detection limits (LODs) were 0.14 -0.95 ng/mL for whole blood and 0.13 -0.93 ng/mL for plasma. The method is simple and sensitive for the determination of benzodiazepines in human whole blood and plasma, and may be useful in forensic science practice.

A rapid, selective, sensitive, and specific method is presented to simultaneously quantify morphine, 6-monoacetylmorphine (6-MAM), codeine, heroin, fentanyl, and methadone in human whole blood and plasma. The drugs were extracted with phosphate buffer at pH 6, followed by solid-phase extraction (SPE) and quantification by GC/MS with electron impact ionization using helium as carrier gas. Quantification was performed based on nalorphine as internal standard (IS). The specificity, linearity, intra-and inter-assay precision and accuracy, and extraction recovery were fully evaluated. The limits of detection (LODs) were 0.40 -7.63 ng/mL for whole blood and 0.80 -32.00 ng/mL for plasma. The method is fast, simple, and accurate, with the sensitivity and specificity required in forensic and clinical toxicology.

No abstract

The present paper describes a method for the simultaneous determination of cocaine and benzoylecgonine in human whole blood. The drugs were extracted with phosphate buffer at pH 6, followed by solid-phase extraction and quantification by GC/MS with electron impact ionization using helium as carrier gas. Quantification was performed using cocaine-d3 as internal standard in selected ion monitoring mode. The method is very simple, rapid and sensitive. The specificity, linearity, intra-and inter-assay precision and accuracy, and extraction recovery were fully evaluated. The limits of detection were 3.6 ng/mL for cocaine and 6.8 ng/mL for benzoylecgonine. The method was applied to blood samples removed at autopsy from body packers and stuffers cases in the I -IV and XV regions of Chile during 2008-2010.

A simple and rapid analytical method is developed and validated for the determination of antiepileptic and antipsychotic drugs in human whole blood using a solid-phase extraction and quantification by gas chromatography-mass spectrometry (GC/MS). Prazepam was used as internal standard (IS). The specificity, linearity, intra-and inter-assay precision and accuracy, and extraction recovery were fully evaluated. The limits of detection and quantification were in the range of 0.52 -0.98 mg/mL and 1.56 -2.97 mg/mL for antiepileptic drugs (pentobarbital, phenobarbital and carbamazepine) and 1.31 -2.94 ng/mL and 3.98 -8.89 ng/mL for antipsychotic drugs (chlorpromazine and thioridazine), respectively. The relative standard deviation (RSD) was less than 7.07%, while the intra-day accuracy was < 3.21% and the inter-day was < 8.80%, referred to RSD. The developed methodology was applied in forensic cases of death caused by phenothiazines in the North of Chile during 2010-2012.

The consumption of antidepressant drugs has increased in these last years, leading to severe and lethal poisonings. In this work, analytical tools, namely GC/MSD and GC/NPD/μECD, were used to identify and quantify several antidepressant drugs including amitriptyline, imipramine, sertraline, fluoxetine, and citalopram in forensic cases in the North of Chile during 2008-2011. Drugs were analyzed in biological arrays like blood. A solid phase extraction by Bond Elut Certify columns was applied in all these processes. Fluoxetine and sertraline were derivatized with pentafluoropropionic anhydride. Prazepam was used as internal standard (IS). The limit of detection (LOD) in blood were 0.5-20.07 ng/mL. The average extraction rate was 89.39% in blood. The relative standard deviation (RSD) was less than 3.6%, while the intra-day accuracy was < 5.5% and the inter-day was < 2.4%, referred to RSD. The procedures we have developed allow the quantification of drugs even at low therapeutic doses, a very important issue taking into account the nature of the analyzed arrays.