QuEChERS extraction of benzodiazepines in biological matrices

Abstract

Two common analytical chemical problems often encountered when using chromatographic techniques in drug analysis are matrix interferences and ion suppression. Common sample preparation often involves the dilution of the sample prior to injection onto an instrument, especially for liquid chromatography–mass spectrometry (LC–MS) analyses. This practice frequently does not minimize or eliminate conditions that may cause ion-suppression and therefore, suffer more from reduced method robustness. In order to achieve higher quality results and minimize possible interferences, various sample preparation techniques may be considered. Through the use of QuEChERS (“catchers”), a novel sample preparation technique used for high aqueous content samples, benzodiazepines can be extracted from biological fluids, such as blood and urine. This approach has shown increased recoveries of target compounds when using quantification by both external and internal standard. This increase in the recoveries has been attributed to a matrix enhancement and was determined through the use of the method of standard addition. While improving the overall analytical method for gas chromatography–mass spectrometry (GC–MS) analysis, it is not clear if this approach represents an overall benefit for laboratories that have both GC–MS and high performance liquid chromatography tandem mass spectrometry (HPLC–MS/MS) capability. Demonstrating evidence of variable ionization (enhancement, ion source inertness, etc.), the method of quantification should be focused on in future studies.

Determination of Diazepam and Clonazepam in Natural Water – a Voltammetric Study

“…Benzodiazepines (BDZs) are frequently employed to treat psychiatric disorders, such as anxiety, panic syndrome, insomnia and as muscle relaxer and anticonvulsants . BDZs interact with the γ‐aminobutyric acid (GABA) receptor, increasing the ion conduction and causing anti‐anxiety, hypnotic and sedative effects . These drugs have been used since 1960 instead of barbiturates due to being safer .…”

The emergence of new psychoactive substance (NPS) benzodiazepines: A review

“…151 The use of a primary and secondary amine phase (PSA) allows easier removal of complex matrix components such as blood. 152 The QuEChERS technique has been shown to increase the recoveries of benzodiazepines extracted from various biological matrices such as blood and urine 153 and from milk-based alcoholic drinks (where benzodiazepines are often added illicitly) which provides a complex matrix for extraction as a result of the high number of proteins and fatty acids. 154 The methods that are currently available for the detection and quantitation of NPS-benzodiazepines in body fluids are listed in Table 7.…”

Effect of agricultural pesticide on precocious puberty in urban children: an exploratory study

“…Sample pretreatment was carried out with QuEChERS (quick, easy, cheap, effective, rugged, and safe) and dispersive solid phase extraction (dSPE) kits (EN15662 method). 16,17) Two millimeters each of prepared sample (urine) and acetonitrile (MeCN) was dis pensed into a centrifuge tube along with internal standard solution (0.1mg/L triphenyl phosphate). The tubes were then vortexed for 1 minute on a shaker at maximum speed.…”