MEKC-MS/MS method using a volatile surfactant for the simultaneous determination of 12 synthetic cannabinoids: Electrodriven Separations

Preparation of pH-responsive block copolymers for separation of cephalosporin antibiotics by open-tubular capillary electrochromatography

Stimuli-responsive block copolymers have exhibited their feasibility for drug delivery and analysis of biomolecules. However, study of the electrophoretic behavior of antibiotics by open tubular capillary electrochromatography (OT-CEC) based on smart block copolymers coatings is still a substantial challenge. Herein, we reported an OT-CEC protocol for analysis of cephalosporin antibiotics with pH-responsive block copolymers as coatings. By using the reversible addition-fragmentation chain-transfers radical polymerisation technique, the smart poly(styrene-maleic anhydride-acrylic acid) (P(St-MAn-AA)) was synthesized and subsequently chemical bonded onto the inner walls of amino-grafted capillaries. The pH induced changes in the stretch/curl states of P(St-MAn-AA) chains were used to generate an adjustable hydrophobic/hydrophilic interaction and hydrogen bonds between the polymer coatings and the analytes. The OT-CEC performance was evaluated by varying the monomer ratios, polymer coating amounts and layers, buffer concentrations and pH values. Baseline separation of the three-test antibiotics was achieved at pH 8.0. The proposed OT-CEC technique was further applied to the determination of rat serum antibiotics in the metabolic processes. The present work demonstrates an enhancement in antibiotics separation efficiency, and shows a great potential for the preparation of stimuli-responsive block copolymers coatings and in OT-CEC analysis of real samples in living bio-systems.

Rapid Simultaneous Determination of 11 Synthetic Cannabinoids in Urine by Liquid Chromatography-Triple Quadrupole Mass Spectrometry

Synthetic cannabinoids are a series of synthetic substances that mimic the effects of natural cannabinoids and produce a much stronger toxicity than natural cannabinoids, and they have become the most abused family of new psychoactive substances. A solid-phase extraction–liquid chromatography–triple quadrupole/linear ion trap mass spectrometry method has been developed to determine 11 synthetic cannabinoids in rat urine. Oasis HLB cartridge was selected to simultaneously extract synthetic cannabinoids for pretreatment. The effects of the loading solution and elution reagent volume on the recovery were investigated. The optimized acetonitrile proportion and elution reagent volume were determined by both high recovery and low solvent consumption. The results showed that the linear coefficients of determination of 11 types of synthetic cannabinoids ranged from 0.993 to 0.999, the limit of quantitation ranged from 0.01 to 0.1 ng/mL, and the spiked recoveries ranged from 69.90% to 118.39%. The research presented here provides a validated liquid chromatography tandem mass spectrometry method to accurately identify and quantitate synthetic cannabinoid metabolites in urine samples.

Applications of Capillary Electrophoresis for the Determination of Cannabinoids in Different Matrices

Cannabinoids, terpenophenolic chemicals found only in cannabis, are primarily responsible for cannabis pharmacologic effects; nearly 150 distinct cannabinoids have been identified thus far. Among these, the main psychoactive molecule, tetrahydrocannabinol (THC), and the non-psychoactive counterpart, cannabidiol (CBD) are distinguishable. In the past decade, a CBD-containing pharmaceutical preparation was approved by Food and Drug Administration (FDA) for the treatment of drug-resistant epileptic seizures in children, and research trials for a variety of additional medical conditions for which CBD has been suggested as a therapy are being conducted. Additionally, the number of "CBD-containing" dietary supplements, largely available online, is increasing rapidly. Consequently, the necessity for the development of qualitative and quantitative methodologies for the analysis of the bioactive components of Cannabis is rising because of the increase in the production of therapeutic cannabis products. One of the analytical methods with good potential in cannabinoids analysis is capillary electrophoresis (CE). It has advantages related to high separation efficiency, relatively short analysis time, and the small consumption of analytes and reagents which generates relatively lower operational costs than other methods. This review focuses on the use of CE techniques to examine biological matrices and plant materials for the presence of cannabinoids and other bioactive compounds found in cannabis. The advantages, drawbacks, and applicability of the various electromigration approaches are also assessed. The article provides an overview of the "state of the art" and the latest trends in CE-based methods for the determination of cannabinoids.

Environmental occurrence and ecological risks of psychoactive substances

Psychoactive substances are ubiquitous in the environment at low concentrations, and tobacco, cannabis, etc. are all widely-existing examples. Given their potent biological activity, psychoactive substances are suspected to be harmful to the environment, and reports of their ecological risks are gradually increasing. Since the 1990s, the investigations into psychoactive substances have made remarkable progress, yet some research fields still need to be modernised. For example, the unification of standardised analytical methods as well as the supplementation of occurrence literature. In addition, a relatively lagging risk evaluation system caused by a lack of toxicity data is particularly in need of improvement. The purpose of this article is to develop a review of current research on psychoactive substances, including analytical methods, distribution in environmental compartments, and ecological risk assessment, as well as to point out deficiencies and development prospects and to offer motivation for enhancing the research level in this field.

Cannabinoids: Recent Updates on Public Perception, Adverse Reactions, Pharmacokinetics, Pretreatment Methods and Their Analysis Methods

Cannabinoids (CBDs) have been traditionally used as a folk medicine. Recently, they have been found to exhibit a high pharmacological potential. However, they are addicted and are often abused by drug users, thereby, becoming a threat to public safety. CBDs and their metabolites are usually found in trace levels in plants or in biological matrices and, are therefore not easy to be detected. Advances have been made toward accurately analyzing CBDs in plants or in biological matrices. This review aims at elucidating on the consumption of CBDs as well as its adverse effects and to provide a comprehensive overview of CBD pretreatment and detection methods. Moreover, novel pretreatment methods such as microextraction, Quick Easy Cheap Effective Rugged Safe and online technology as well as novel analytic methods such as ion-mobility mass spectrometry, application of high resolution mass spectrometry in nontarget screening are summarized. In addition, we discuss and compare the strengths and weaknesses of different methods and suggest their future prospect.

Nonaqueous capillary electrophoresis mass spectrometry method for determining highly hydrophobic peptides

A nonaqueous capillary electrophoresis mass spectrometry (NACE-MS) method was developed to separate and determine highly hydrophobic temporin peptides. The nonaqueous background electrolyte solution was a mixture of 20% acetonitrile, 78% methanol and 2% formic acid, with 20 mM ammonium formate. The separation of six peptides was completed within 12 min. The CE system was connected to a triple quadrupole mass spectrometer operating in MRM mode using a chemical modifier solution of 2 mM ammonium formate in ethanol with the flow through microvial interface. The mass spectrometer offered a second dimension of separation for peptides having identical migration times but different structures. The new method represents the first system capable of reliably determining hydrophobic peptides without using reversed phase liquid chromatography mass spectrometry.

Fully compatible and ultra-sensitive micellar electrokinetic chromatography-tandem mass spectrometry using sheathless porous-tip interfacing

The on-line coupling of micellar electrokinetic chromatography and mass spectrometry (MEKC-MS) is often hampered by incompatibility problems leading to reduced separation performance and unfavorable limits of detection (LODs). Here we propose a new selective and highly sensitive MEKC-MS/MS method employing a sheathless porous-tip interface in combination with a micellar phase comprised of semi-volatile surfactant molecules. Carbamate pesticides (CRBs) were selected as representative model compounds being neutral toxic pollutants potentially present at trace levels in environmental water samples. A background electrolyte of 75mM perfluorooctanoic acid adjusted to pH 9.0 with ammonium hydroxide allowed efficient separation of 15 CRBs and appeared fully compatible with electrospray ionization (ESI)-MS. Interfacing parameters, such as the distance between the capillary tip and mass-spectrometer inlet, ESI voltage, and dry gas temperature and flow were optimized in order to attain good spray stability and high analyte signal-to-noise ratios. For CRBs the LODs ranged from 0.2 to 3.9ngL^-1 (13nL injected, i.e., 2% of capillary volume), representing an improvement for certain CRBs of more than 300-fold when compared with conventional sheath-liquid interfacing. Good linearity (R²>0.99) and satisfactory reproducibility were obtained for all CRBs with interday RSD values for peak area and migration time of 4.0-11.3% and below 1.5%, respectively. Analysis of spiked mineral water showed that the new MEKC-MS/MS method allows selective and quantitative determination of CRB concentrations below the maximum residue limit of 100ngL^-1 without the need for sample preconcentration.

Rapid analysis of synthetic cannabinoids using a miniature mass spectrometer with ambient ionization capability

Synthetic cannabinoids are an emerging class of drugs of abuse and are of a great concern for transport control and usage regulation. In this study, we have developed rapid analytical methods using a miniature mass spectrometer for the identification of synthetic cannabinoids, as the traces of bulk powders on surfaces or substances in blood and urine. Significantly simplified work flows were developed by employing two ambient ionization methods, the paper spray and extraction spray ionization. Using five synthetic cannabinoids as examples, a limit of detection of 2 ng was estimated for the detection of trace powders on a bench surface and limits of quantitation as good as 10 ng/mL were obtained for the analysis of blood and urine samples.

The role of ultra high performance liquid chromatography with time of flight detection for the identification of synthetic cannabinoids in seized drugs

Separation and mass spectrometric techniques are integral parts of forensic drug analysis for both screening and confirmation. The Scientific Working Group for the Analysis of Seized Drugs (SWGDRUG), which is responsible for setting standards for drug analysis, requires for drug identification a Category A test such as mass spectrometry with an additional test from either Category B or C. If a Category A method is not used at least two uncorrelated tests from Category B must be included, for which separation techniques such as gas chromatography and liquid chromatography would qualify. The utility and validity of using ultra high performance liquid chromatography (UHPLC) and time-of-flight (TOF) mass spectrometry (MS) for the analysis of synthetic cannabinoids is presented. The separation of 32 solutes, including 23 controlled substances and nine non-controlled positional isomers of JWH-018, are compared using UHPLC with TOF detection and capillary GC with electron ionization (EI). For these solutes, the reversed phase UHPLC separation on three different 2.1 mm × 150 mm × 2.7 μm superficially porous (SPP) columns (C18, Phenyl-Hexyl and Dimethylpentafluorophenylpropyl (PFP)) compared favorably with the capillary gas chromatography (GC) separation using an Elite-5MS column 0.25 mm × 30 m × 0.25 μm. Principal component analysis revealed that all three UHPLC separations for the separation of the controlled substances are orthogonal to the capillary GC separation. It was also revealed by principal component analysis that the separation of JWH-018 and the nine non-controlled positional isomers for the various techniques were significantly more correlated than the separation of the controlled substances. Although most of the controlled synthetic cannabinoids gave unique TOF in-source collision-induced dissociation MS spectra and EI spectra, it was not possible to discriminate among the geometric isomers (CP47, 497, Epi CP47, 497; Cp47, 497 C8 homologue, Epi CP47, 497 C8 homologue). JWH-018 could be distinguished from the non-controlled isomers based on its EI spectra. In contrast, several of the non-controlled JWH-018 isomers give identical TOF in-source collision-induced dissociation MS spectra to JWH-018.

Determination and identification of synthetic cannabinoids and their metabolites in different matrices by modern analytical techniques - a review

Synthetic cannabinoids have gained popularity due to their easy accessibility and psychoactive effects. Furthermore, they cannot be detected in urine by routine drug monitoring. The wide range of active ingredients in analyzed matrices hinders the development of a standard analytical method for their determination. Moreover, their possible side effects are not well known which increases the danger. This review is focused on the sample preparation and the determination of synthetic cannabinoids in different matrices (serum, urine, herbal blends, oral fluid, hair) published since 2004. The review includes separation and identification techniques, such as thin layer chromatography, gas and liquid chromatography and capillary electrophoresis, mostly coupled with mass spectrometry. The review also includes results by spectral methods like infrared spectroscopy, nuclear magnetic resonance or direct-injection mass spectrometry.