Fast Hollow Fiber Liquid-Phase Microextraction as a Greener Alternative for the Determination of N,N-Dimethyltryptamine and Harmala Alkaloids in Human Urine

Analytical Methods for Determining Psychoactive Substances in Various Matrices: A Review

Psychoactive substances pose significant challenges and dangers to society due to their impact on perception, mood, and behavior, leading to health and life disturbances. The consumption of these substances is largely influenced by their legal status, cultural norms, and religious beliefs. Continuous development and chemical modifications of psychoactive substances complicate their control, detection, and determination in the human body. This paper addresses the terminological distinctions between psychoactive and psychotropic substances and drugs. It provides a comprehensive review of analytical methods used to identify and quantify 25 psychoactive substances in various biological matrices, including blood, urine, saliva, hair, and nails. The analysis categorizes these substances into four primary groups: stimulants, neuroleptics, depressants, and hallucinogens. The study specifically focuses on chromatographic and spectrophotometric methods, as well as other novel analytical techniques. Methodology includes a review of scientific articles containing validation studies of these methods and innovative approaches to psychoactive substance determination. Articles were sourced from the PubMed database, with most research originating from the twenty first century. The paper discusses the limits of detection and quantitation for each method, along with current trends and challenges in the analytical determination of evolving psychoactive substances.

Comparative study of sample preparation procedures to determine the main compounds in ayahuasca beverages by QuEChERS and high-performance liquid chromatography analysis

INTRODUCTION

Ayahuasca is a psychoactive drink originally consumed by indigenous people of the Amazon. The lack of regulation of this drink leads to uncontrolled consumption, and it is often consumed in religious contexts.

OBJECTIVE

The aim of this work is to compare three miniaturised extraction techniques for extracting the main ayahuasca compounds from beverages.

METHODOLOGY

Three sample pretreatment techniques were evaluated (dispersive liquid-liquid microextraction [DLLME], microextraction by packed sorbent [MEPS] and QuEChERS [Quick, Easy, Cheap, Effective, Rugged and Safe]) for the simultaneous extraction of N,N-dimethyltryptamine (DMT), tetrahydroharmine (THH), harmine, harmaline, harmol and harmalol from ayahuasca beverage samples. Then, the most promising technique (QuEChERS) was chosen to pre-concentrate the analytes, subsequently detected by high-performance liquid chromatography coupled to a diode array detector (HPLC-DAD).

RESULTS

The procedure was optimised, with the final conditions being 500 μL of extractor solvent, 85 mg of primary secondary amine (PSA) and 4 s of vortexing. The analytical method was validated, showing to be linear between 0.16 and 10 μg/mL for β-carbolines and between 0.016 and 1 μg/mL for DMT, with coefficients of determination (R2) between 0.9968 and 0.9993. The limit of detection (LOD) and lower limit of quantification (LLOQ) were 0.16 μg/mL for all compounds, except for DMT (0.016 μg/mL) and extraction efficiencies varied between 60.2% and 88.0%.

CONCLUSION

The analytical methodology proved to be accurate and precise, with good linearity, LODs and LLOQs. This method has been fully validated and successfully applied to ayahuasca beverage samples.

Extraction performance of electromembrane extraction and liquid-phase microextraction in prototype equipment

In this comparative study, the performance of liquid-phase microextraction and electromembrane extraction in prototype equipment was evaluated for extraction of ninety basic substances from plasma. Using a commercial EME device based on conductive vials enabled a standardized and comprehensive comparison between the two methods. Extractions were performed from a pH-adjusted donor solution, across an organic liquid membrane immobilized in a porous polypropylene membrane, and into an acidic acceptor solution. In LPME, dodecyl acetate was used as the extraction solvent, while 2-nitrophenyl octyl ether was used for EME with an electric field applied across the system. To assess the extraction performance, extraction recovery plots and extraction time curves were constructed and analyzed. These plots provided insights into the efficiency and effectiveness of LPME and EME, allowing users to make better decisions about the most suitable method for a specific bioanalytical application. Both LPME and EME were effective for substances with 2.0 < log P < 4.0, with EME showing faster extraction kinetics. Small (200 µL) and large vials (600 µL) were compared, showing that smaller vials improved kinetics markedly in both techniques. Carrier-mediated extraction showed improved performance for analytes with log P < 2 in EME, however, with some limitations due to system instability. This is, to our knowledge, the first time LPME was performed in the commercial vial-based equipment. An evaluation of vial-based LPME investigating linearity, precision, accuracy, and matrix effects showed promising results. These findings contribute to a general understanding of the performance differences in vial-based LPME and EME.

A study on the enrichment mechanism of three nitrophenol isomers in environmental water samples by charge transfer supramolecular-mediated hollow fiber liquid-phase microextraction

To explore the mechanism of extraction and enrichment of three nitrophenol isomers by charge-transfer supramolecular synergistic three-phase microextraction system, a charge transfer supramolecular-mediated hollow fiber liquid-phase microextraction (CTSM-HF-LPME) combined with high-performance liquid chromatography-ultraviolet detector (HPLC-UV) method was established for the determination of real environmental water samples. In this study, the three nitrophenols (NPs) formed charge-transfer supramolecules with electron-rich hollow fibers, which promoted the transport of NPs in the three-phase extraction system and greatly increased the EFs of NPs. The relationships between the EFs of NPs and their solubility, pK_a, apparent partition coefficient, equilibrium constant, and structural property parameters were investigated and discussed. At the same time, most of factors affecting the EFs of NPs were investigated and optimized, such as the type of extraction solvent, pH value of sample phase and acceptor phase, extraction time, and stirring speed. Under optimal conditions, the EFs of o-nitrophenol, m-nitrophenol, and p-nitrophenol were 163, 145, and 87, respectively. With good linearity in the range of 5 × 10^-7 ~ 1 µg/mL, and the limit of detection of 0.1 pg/mL, the relative standard deviations of the method precision were lower than 7.4%, and the average recoveries were between 98.6 and 106.4%. This method had good selectivity and sensitivity, satisfactory precision, and accuracy and had been successfully applied to the trace detection of real water samples.

Beyond the Psychoactive Effects of Ayahuasca: Cultural and Pharmacological Relevance of Its Emetic and Purging Properties

The herbal preparation ayahuasca has been an important part of ritual and healing practices, deployed to access invisible worlds in several indigenous groups in the Amazon basin and among mestizo populations of South America. The preparation is usually known to be composed of two main plants, Banisteriopsis caapi and Psychotria viridis, which produce both hallucinogenic and potent purging and emetic effects; currently, these are considered its major pharmacological activities. In recent decades, the psychoactive and visionary effect of ayahuasca has been highly sought after by the shamanic tourism community, which led to the popularization of ayahuasca use globally and to a cultural distancing from its traditional cosmological meanings, including that of purging and emesis. Further, the field of ethnobotany and ethnopharmacology has also produced relatively limited data linking the phytochemical diversity of ayahuasca with the different degrees of its purging and emetic versus psychoactive effects. Similarly, scientific interest has also principally addressed the psychological and mental health effects of ayahuasca, overlooking the cultural and pharmacological importance of the purging and emetic activity. The aim of this review is therefore to shed light on the understudied purging and emetic effect of ayahuasca herbal preparation. It firstly focuses on reviewing the cultural relevance of emesis and purging in the context of Amazonian traditions. Secondly, on the basis of the main known phytochemicals described in the ayahuasca formula, a comprehensive pharmacological evaluation of their emetic and purging properties is presented.

Ultrasound-assisted solid phase microextraction-HPLC method based on Fe3O4@SiO2-NH2-molecularly imprinted polymer magnetic nano-sorbent for rapid and efficient extraction of harmaline from Peganum harmala extract

In the present study, a magnetic molecularly imprinted polymer (MMIP) was synthesized for the extraction of harmaline from Peganum harmala by dispersive solid-phase microextraction (DSPME). The MMIP for selective and intelligent extraction of harmaline with excellent functionality and high selectivity was synthesized using the sol-gel method with functionalized superparamagnetic core-shell nanoparticles, ethylene glycol dimethacrylate (EDMA) as a cross-linker, methacrylic acid (MAA) as a functional monomer, and 2,2-azobisisobutyronitrile (AIBN) as a porogen. To study the properties and morphology of the coated polymer, FT-IR spectroscopy, FESEM, TEM images, and VSM were used. The DSPME-HPLC-UV equipment was used to quantify and analyze the data obtained from harmaline extraction. In this research, the efficiency of the synthesized polymer in harmaline extraction was modeled and optimized using the response surface methodology based on central composite design (RSM-CCD). In addition, for modeling the isotherm of harmaline sorption by the MMIP, Langmuir and Freundlich isotherm equations were used. The obtained results showed that the extraction of harmaline with the MMIP was well described with Freundlich isotherm. The results of the validation of the method showed that the measurement of harmaline in the concentration range of 1.0-4000 ng mL^-1 followed a linear relationship (R² = 9986.0). Moreover, the accuracy or repeatability index (% RSD) was determined to be < 10, and the LOQ and LOD values were 0.526 and 0.158 ng mL^-1, respectively. The results of this study showed that the DSPME technique by using the synthesized MMIP as an effective sorbent with high efficiency and capacity could be utilized for pre-concentration and extraction of harmaline from real and complex samples.

Essential oil-based dispersive liquid-liquid microextraction for the determination of N,N-dimethyltryptamine and β-carbolines in human plasma: A novel solvent-free alternative

The present study describes the development of a novel solvent-free vortex-assisted dispersive liquid-liquid microextraction alternative based on a natural essential oil as extracting solvent (VA-EO-DLLME) for the determination of N,N-dimethyltryptamine (DMT), harmine (HRM), harmaline (HRL) and tetrahydroarmine (THH) (compounds found in the ayahuasca tea, a psychedelic plant preparation) in human plasma. After optimization through full factorial and Box-Behnken experimental designs, this VA-EO-DLLME followed by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was completely validated and applied to authentic plasma specimens. Sample preparation consisted in the addition of 60 mg of NaCl, 100 μL of borate buffer and 100 μL of Eucalyptus globulus essential oil to a 200 μL aliquot of human plasma. After 30 s of vortex agitation followed by 5 min of centrifugation (10,000 rpm), 80 μL of the oil supernatant was dried and resuspended in mobile phase prior to injection into the UHPLC-MS/MS system. Once optimized, the validated method yielded LoDs ≤1.0 ng mL^-1 for all analytes. LoQ was 1.0 ng mL^-1 for DMT, HRL and HRM and 2.0 ng mL^-1 for THH. The method has shown to be linear over the range of LoQ up to 150 ng mL^-1 (r² ≥ 0.9926). Intra/inter-day precision and accuracy met the acceptance criteria at three quality control (QC) levels. An additional intermediate precision study demonstrated that, except for THH and HRL at low and medium QCs, the overall method performance was similar for the three different oil sources. Matrix effect evaluation showed predominant ion suppression, ranging from 56% to 83%. Recovery varied from 33 up to 101% with an average of 50 ± 15.8%. Selectivity studies showed no interferences. Analysis of 13 authentic samples proved method feasibility. Finally, we believe that our novel VA-EO-DLLME approach offers a very simple, fast, cost-effective and eco-friendly alternative based on the use of an easily accessible and entirely green material as an extracting solvent. This may represent an incentive for researchers to investigate novel and creative alternatives, such as essential oils, as substitutes of organic solvents for microextraction methods in forensic and clinical contexts.