No abstract

Disposable pipette tips extraction consists of a solid-phase extraction in which the sorbent is poorly dispersed in a pipette tip, which allows a quick and dynamic contact between the aspirated analyte from the sample and the solid phase. It is a technique used particularly in food and forensic analysis, since it requires a small amount of sample and solvent. This article highlights the principles, advantages and disadvantages of the disposable pipette tips extraction method and reviews recent applications.

Drug abuse by pregnant women is considered a serious public health problem worldwide. Meconium is the first excretion in newborns and has been used as an alternative matrix to evaluate in utero drug exposure. Solid phase extraction (SPE) is widely employed to prepare and clean up samples in the field of forensic analysis. Most SPE products require large volumes of solvent, which culminates in longer sample processing times and increased cost per sample. Disposable pipette extraction (DPX) tips have been used as an alternative to traditional SPE cartridges. They combine efficient and rapid extraction with reduced solvent consumption. The purpose of this study was to develop and validate a method to determine nicotine, cotinine, cocaine, benzoylecgonine, cocaethylene and methyl ester anhydroecgonine in meconium using DPX and gas chromatography-mass spectrometry (GC-MS). Validation results indicated that extraction efficiency ranged 50-98%, accuracy 92-106%, intra-assay precision 4-12% and inter-assay precision 6-12%. Linear calibration curves resulted in R(2) values >0.99, limits of detection ranged from 2.5 to 15 ng/g and the limit of quantitation from 10 to 20 ng/g. The DPX-GC-MS method was shown to selectively analyze trace concentrations of drugs in meconium samples. Finally, the developed and validated method was applied to 50 meconium samples.

BORDIN, D.C.M. Fetal Exposure: determination of drugs of abuse in meconium using solid phase extraction modified and gas chromatography coupled to mass spectrometry. 2013. 85 p. Dissertation (Master).

Bordin, Dayanne Cristiane Mozaner. Sweat as an alternative sample in doping control. 2017. 149p. Thesis Doctor degree. School of Pharmaceutical Sciences-USP and Centre of Forensic Sciences-UTS. 2017. Sport has become a major industry of valuable awards and major investments. In an attempt to overcome opponents, many athletes resort to illegal means to improve their performance. The World Antidoping Agency (WADA) prohibits drug use in sport. In addition to the ethical aspects, drug use can cause serious damage to an athletes' health by directly influencing physiological capacity and removing physical and psychological barriers, and their health damage may be irreversible. Urine is the standard matrix used in doping control; however, these analyses can also be performed on alternative biological samples; such as sweat. Toxicological analysis in sweat samples present some advantages over urine, such as less chance of sample tampering, greater detection window, noninvasive collection, besides the possibility of finding mainly the parent drugs. The use of sweat as an alternative sample also allows obtaining a history of exposure to drug abuse. The identification of doping cases has been an important area of research and development in recent years due to the continued increase in the number of prohibited substances. For the detection of prohibited substances, sophisticated analytical instruments such as liquid (LC), gas (GC) chromatography coupled to mass spectrometry and capillary electrophoresis (CE) are generally used. This thesis focused on the development of methods for evaluation of sweat as an alternative biological matrix for doping control, using different methods for sample preparation and detection to overcome its limitations. In addition, an outline of the profile of drugs used for sports practice and the acute effects caused in the organism of abusers were investigated. A survey was applied to the volunteers to evaluate the adverse effects of androgenic anabolic steroids (AAS), dietary supplements (DS) and multiple drug use. In parallel, it was measured the volunteers hematological and biochemical parameters. Through toxicological urinalysis, the self-report and the parameters measurement within the study revealed that the use of doping agents and drugs are subjected to different factors, which are normally guided by the type of physical activity or aesthetic appearance. This abuse can increase the chances of health problems causing synergistic side effects, increasing the risk to develop diseases. We developed of a method to determine the presence of 13 amphetamines and cocaine related substances and their metabolites in sweat and urine using Disposable Pipette Extraction (DPX) Tips and GC-MS. The validated method was used to analyze 40 urine and sweat samples whose athletes self-reported the use of drugs and/or stimulants. It was verified that all consumed drugs and metabolites detected in urine were also present in sweat samples indicating that sweat is a viable matrix to perform doping tests. We also ...