Dispersive solid‐phase extraction adsorbent of methamphetamine using in‐situ synthesized carbon‐based conductive polypyrrole nanocomposite: focus on clinical applications in human urine

Brewer's spent grain as a potential sorbent for toxicology methods: Application to antidepressant analysis in urine

The use of antidepressants is well-documented for several health conditions. The determination of these drugs in biological fluids is often important in intoxication cases. However, appropriate sample preparation needs to be employed, such as dispersive liquid phase microextraction (DSPME). Therefore, this study aimed to develop a method for the determination of antidepressants in urine using Brewer's spent grain (BSG) as sorbent in a DSPME procedure, followed by GC-MS analysis. In this methodology, only 500 µL of urine was required, alongside 15 mg of BSG as the sorbent for the DSPME technique. Desorption step was performed with 500 µL of ethyl acetate:MTBE solution (1:1, v/v), followed by evaporation of the organic layer, reconstitution in acetonitrile and injection into the analytical system. BSG was further characterized by several analytical techniques. The DSPME procedure was optimized using multivariate strategies, and the method was fully validated according to proper guidelines. Lower limits of quantitation (LLOQ) were set between 50 and 200 ng/mL, while linearity was achieved over the specified range of LLOQ to 5000 ng/mL, with R2 ≥ 0.99. Additionally, the method was applied to the analyses of 109 urine samples. Of these, 76 were positive for at least one antidepressant, with the most prevalent being nortriptyline, amitriptyline, and fluoxetine. This study is the first to report the use of BSG as a sorbent for DSPME, demonstrating good efficiency as indicated by the analytical figures of merit. Moreover, the method proved to be applicable in real poisoning case samples. The analytical performance, combined with advantages such as high throughput and a green profile, suggests this method as a valuable alternative for toxicological laboratories.

Extraction of methamphetamine and pseudoephedrine by modified graphene oxide solid phase extraction method coupled to HPLC-UV in urine sample

Methamphetamine, pseudoephedrine, and related drugs are among the first drugs used for the stimulation of the central nervous system. In this study, two adsorbents based on graphene oxide (GO) were synthesized and used for the analysis of methamphetamine and pseudoephedrine. The prepared nano-adsorbents based on GO in this study were coated by polyaniline (PANI) and Fe3O4/C-nanodot/GO (magnetic adsorbent). The average size of nanoparticles (GO/PANI) was 18.43 nm. The specific surface area and pore size diameter of Fe3O4/C-nanodot/GO were 22.71 m2 g- 1 and 15.23 nm, respectively. Experimental variables affecting the extraction efficiency of the analytes such as pH of the sample solution, amount of adsorbent, extraction time, and type of eluents were investigated and optimized by response surface methodology. Under optimum conditions, GO/PANI and Fe3O4/C-nanodot/GO were considered appropriate solid phase extraction adsorbents for HPLC-based analyses of the studied drugs in human urine samples. However, GO/Fe3O4 nano adsorbent (Fe3O4/C-nanodot/GO) showed superior working condition than GO/PANI. The validated proposed analytical methods can be used for the quantitative determination of methamphetamine and pseudoephedrine in actual samples.

Microextraction Techniques for Sample Preparation of Amphetamines in Urine: A Comprehensive Review

Psychological disorders and dramatic social problems are serious concerns regarding the abuse of amphetamine and its stimulant derivatives worldwide. Consumers of such drugs experience great euphoria along with serious health problems. Determination and quantification of amphetamine-type stimulants are indispensable skills for clinical and forensic laboratories. Analysis of low drug doses in bio-matrices necessitates applications of simple and also effective preparation steps. The preparation procedures not only eliminate adverse matrix effects, but also provide reasonable clean-up and pre-concentration benefits. The current review presents different methods used for sample preparation of amphetamines from urine as the most frequently used biological matrix. The advantages and limitations of various sample preparation methods were discussed focusing on the miniaturized methods.

Research progress on pretreatment technology for the analysis of amphetamine biological samples

Sample pretreatment technology is crucial for drug analysis and detection, because the effect of sample pretreatment directly determinates the final analysis results. In recent years, with the continuous innovation of microextraction and other technologies like material preparation technologies and assistant technologies for extraction, the sample pretreatment techniques in the process of drug analysis have become more and more mature and diverse. This article takes amphetamine (AM) or methamphetamine as an example to review the recent development of pretreatment methods for AM-containing biological samples from the perspectives of extraction techniques, extraction media and auxiliary technologies. Extraction techniques are summarized with the categories of contact microextraction, separate microextraction and membrane-based microextraction for better guidance of application according to their features. Prevailing and innovative extraction media including carbon-based material, silicon-based material, metal organic framework, molecularly selective materials, supramolecular solvents and ionic liquids are reviewed. Auxiliary technologies like magnetic field, electric field, microwave, ultrasound and so on which can enhance extraction efficiency and accuracy are also reviewed. In the last, prospects of the future development of pretreatment technology for the analysis of AM biological samples are provided.

Conductive Polymer-Based Nanocomposites as Powerful Sorbents: Design, Preparation and Extraction Applications

Conductive polymers as composite materials have been attracted tremendous attention due to their versatile and excellent features such as tunable conductivity, facile synthesis and fabrication, high chemical and thermal stability etc. These characteristics make them versatile and let them being used in numerous fields including microelectronics, optics and biosensors. Throughout the mentioned fields, conductive polymers particularly perform as effective sorbents. Although tremendous efforts have been put into this topic, to the best of our knowledge, a comprehensive up-to-date review on the applications of conductive polymers as efficient sorbents has not been reported. The main objective of this paper is to make a significant contribution to the recent literature toward the synthesis and extraction applications of conductive polymers as efficient sorbents.

Application of Microextraction-Based Techniques for Screening-Controlled Drugs in Forensic Context-A Review

The analysis of controlled drugs in forensic matrices, i.e., urine, blood, plasma, saliva, and hair, is one of the current hot topics in the clinical and toxicological context. The use of microextraction-based approaches has gained considerable notoriety, mainly due to the great simplicity, cost-benefit, and environmental sustainability. For this reason, the application of these innovative techniques has become more relevant than ever in programs for monitoring priority substances such as the main illicit drugs, e.g., opioids, stimulants, cannabinoids, hallucinogens, dissociative drugs, and related compounds. The present contribution aims to make a comprehensive review on the state-of-the art advantages and future trends on the application of microextraction-based techniques for screening-controlled drugs in the forensic context.

Sample preparation and instrumental methods for illicit drugs in environmental and biological samples: A review

Detection of illicit drugs in the environmental samples has been challenged as the consumption increases globally. Current review examines the recent developments and applications of sample preparation techniques for illicit drugs in solid, liquid, and gas samples. For solid samples, traditional sample preparation methods such as liquid-phase extraction, solid-phase extraction, and the ones with external energy including microwave-assisted, ultrasonic-assisted, and pressurized liquid extraction were commonly used. The sample preparation methods mainly applied for liquid samples were microextraction techniques including solid-phase microextraction, microextraction by packed sorbent, dispersive solid-phase extraction, dispersive liquid-liquid microextraction, hollow fiber-based liquid-phase microextraction, and so on. Capillary microextraction of volatiles and airborne particulate sampling were primarily utilized to extract illicit drugs from gas samples. Besides, the paper introduced recently developed instrumental techniques applied to detect illicit drugs. Liquid chromatograph mass spectrometry and gas chromatograph mass spectrometry were the most widely used methods for illicit drugs samples. In addition, the development of ambient mass spectrometry techniques, such as desorption electrospray ionization mass spectrometry and paper spray mass spectrometry, created potential for rapid in-situ analysis.

Extraction of Cyproheptadine as Potent Appetizing Stimulant in Herbal Supplements by Efficient Carbon Nitride Nanosheets as Dispersive Solid Phase Extraction Adsorbent

Background: Application of natural-based herbal medicine is on a growing trend in some countries and people prefer to use plant-originated drugs rather than chemical-based ones. The present study describes an interesting sample preparation method for extraction and determination of cyproheptadine in herbal supplements as appetizing stimulant by using carbon nitride nanosheets as dispersive solid phase extraction method coupled with HPLCUV. Methods: Various techniques used for characterization of adsorbent such as: Infrared spectroscopy (IR), scanning electron microscopy (SEM), Zeta potential analysis and powder X-ray diffraction (XRD). Optimization of the important extraction parameters were conducted by one parameter-at-a time method. Next, method validation was carried out. Results: The optimized cyproheptadine extraction parameters were introduced and under optimized conditions the method presented a good linearity in the concentration range of 300-2000 ng/g. The limit of detection (LOD) was 100 ng/g for the introduced method. Conclusion: Quantitative analysis of fifteen real samples (Tablets or capsules) by proposed method confirmed the illegal presence of cyproheptadine in herbal appetizing stimulants supplements of the markets.