New green DI-SPME/CE-MS method for quantitative analysis of selected illicit drugs in human whole blood

The purpose of the research was to develop a new method that would allow the determination of selected drugs (mephedrone, MDMA, and cocaine and its metabolites: benzoylecgonine, norcocaine, and cocaethylene) in whole blood, while meeting not only the criteria of greenness, but also balancing analytical and economic aspects. For this purpose, solid phase microextraction was paired with capillary electrophoresis hyphenated to a mass spectrometer. The method was validated. Parameters such as LOD (1.2–7.2 ng/ml), LOQ (3.7–24.0 ng/ml), intra- (2.24–10.72%) and inter-day (3.97–19.01%) precision, bias (RE=0.1–14.6%), recovery (91.7–105.4%) and matrix effect (-1.8–5.4%, except benzoylecgonine) were determined. In addition to analytical parameters, the greenness of the method and its practicality and cost-effectiveness were also evaluated. The White Analytical Chemistry method was used for this purpose. A high score of 90.6/100.0 was obtained, indicating that the method balances these three aspects very well. On this basis, it was concluded that the developed DI-SPME/CE-MS method could be a useful tool for toxicological analyses

Green aspects in the procedure of detection ketamine, flunitrazepam, and diazepam in drinks based on dried sample spot analysis

A new methodology for the detection of ketamine, flunitrazepam, and diazepam in beverage samples by the dried sample spot method was developed. The method is characterized by very low LODs in all tested types of beverages (100 ng/mL for ketamine, 25 ng/mL for flunitrazepam and diazepam) and great precision at the concentration of 100 ng/mL for all analytes. The significant advantages of this method are the consumption of fewer amount of samples and the possibility of securing the beverage samples on DBS cards at room temperature. The proposed method was evaluated by the innovative WAC approach according to Green Analytical Chemistry. The results of the evaluation indicate the best results of this method in terms of analytical quality compared to the other methods from the literature, however other aspects such as green chemistry and economical are also good. The DBS/MAE/LC-MS method could be used for qualitative analysis for drugs detection in cases of date-rape drugs analysis

The double face of ketamine : the possibility of its identification in blood and beverages

The purpose of this study was to develop and validate a high-sensitivity methodology for identifying one of the most used drugs—ketamine. Ketamine is used medicinally to treat depression, alcoholism, and heroin addiction. Moreover, ketamine is the main ingredient used in so-called “date-rape” pills (DRP). This study presents a novel methodology for the simultaneous determination of ketamine based on the Dried Blood Spot (DBS) method, in combination with capillary electrophoresis coupled with a mass spectrometer (CE-TOF-MS). Then, 6-mm circles were punched out from DBS collected on Whatman DMPK-C paper and extracted using microwave-assisted extraction (MAE). The assay was linear in the range of 25–300 ng/mL. Values of limits of detection (LOD = 6.0 ng/mL) and quantification (LOQ = 19.8 ng/mL) were determined based on the signal to noise ratio. Intra-day precision at each determined concentration level was in the range of 6.1–11.1%, and inter-day between 7.9–13.1%. The obtained precision was under 15.0% (for medium and high concentrations) and lower than 20.0% (for low concentrations), which are in accordance with acceptance criteria. Therefore, the DBS/MAE/CE-TOF-MS method was successfully checked for analysis of ketamine in matrices other than blood, i.e., rose wine and orange juice. Moreover, it is possible to identify ketamine in the presence of flunitrazepam, which is the other most popular ingredient used in DRP. Based on this information, the selectivity of the proposed methodology for identifying ketamine in the presence of other components of rape pills was checked

Determination of selenium as a biomarker of thyroid cancer by HG-AFS method

A simple and versatile procedure has been developed for the determination of selenium in biological samples for clinical purposes. The procedure consists of microwave sample digestion and the determination of selenium using atomic fluorescence spectrometry with a hydride generation system (HG-AFS). The method allows the determination of selenium in a range of 0.5–100.0 μg L–1 with a detection limit not higher than 0.2 μg L–1 and with good repeatability not exceeding 1%. It was applied for determination of selenium in women’s plasma samples (n = 90) with a suspicion of a thyroid cancer and the control group of women (n = 87). Most of the obtained results were in the range 30.0–60.0 μg L–1 and either did not match the physiological level of selenium in human plasma or indicate moderate selenium deficiency. In the further examinations the thyroid tissues taken from 30 patients were analyzed. In most of the cases the selenium concentration was found to be lower (0.14–1.67 μg g–1 wet weight) than its physiological level in a healthy tissue. On this basis the hypothesis has been drawn that selenium can be considered as an additional marker of the thyroid cancer disease

Extraction of colour inkjet printing inks from printouts for forensic purpose

The ability to differentiate between inkjet printing inks is of great interest in document examination. The aim of this work was to develop a procedure for effective ink extraction so that the ink could be reliably analyzed by capillary electrophoresis. Conditions such as type and composition of extracting mixtures, as well as duration of extraction and sonication procedures were taken into consideration. A set of different agents was used to extract inks of inkjet printers produced by Hewlett-Packard, Canon, Brother, Epson and Lexmark. Extraction efficiency was examined visually and then by means of UV/Vis spectrometry. It was ascertained that the most promising extracting agents are mixtures of borate buffer with SDS and with acetonitrile, or alternatively with methanol, which are both suitable background electrolytes for further CE analysis. However, in some exceptional cases, highly efficient extraction was achieved by a mixture of DMF, DMSO, EtOH and MEE with water