Determination of benzodiazepines in beverages using green extraction methods and capillary HPLC-UV detection

Exploiting the potential of fabric phase sorptive extraction for forensic food safety: Analysis of food samples in cases of drug facilitated crimes

Drug-facilitated crimes (DFCs) entail the use of a single drug or a mixture of drugs to render a victim unable. Traditionally, biological samples have been gathered from victims and conducting analysis to establish evidence of drug administration. Nevertheless, the rapid metabolism of various drugs and delays in analysis can impede the identification of such substances. For this, the present article describes a rapid, sustainable, highly efficient and miniaturized protocol for the identification and quantification of three sedative-hypnotic drugs namely diazepam, chlordiazepoxide and ketamine in alcoholic beverages and complex food samples (cream of biscuit, flavoured milk, juice, cake, tea, sweets and chocolate). The methodology involves utilizing fabric phase sorptive extraction (FPSE) to extract diazepam (DZ), chlordiazepoxide (CDP), and ketamine (KET), Subsequently, the extracted sample are subjected to analysis using gas chromatography-mass spectrometry (GC-MS). Several parameters, including type of membrane, pH, agitation time and speed, ionic strength, sample volume, elution volume and time, and type of elution solvent, were screened and thoroughly optimized. Sol-gel Carbowax 20M (CW-20M) has demonstrated most effective extraction efficiency for the target analytes among all evaluated membranes. Under optimal conditions, the method displayed linearity within the range of 0.3-10 µg mL-1 (or µg g-1), exhibiting a coefficient of determination (R2) ranging from 0.996 to 0.999. The limits of detection (LODs) and limits of quantification (LOQs) for liquid samples ranging between 0.020 and 0.069 µg mL-1 and 0.066-0.22 µg mL-1, respectively. Correspondingly, the LODs for solid samples ranged from 0.056 to 0.090 µg g-1, while the LOQs ranged from 0.18 to 0.29 µg g-1. Notably, the method showcased better precision, with repeatability and reproducibility both below 5% and 10%, respectively. Furthermore, the FPSE-GC-MS method proved effective in determining diazepam (DZ) in forensic food samples connected to drug-facilitated crimes (DFCs). Additionally, the proposed method underwent evaluation for its whiteness using the RGB12 algorithm.

Recent Advances in Dispersive Liquid-Liquid Microextraction for Pharmaceutical Analysis

Sample clean-up and pre-concentration are critical components of pharmaceutical analysis. The dispersive liquid-liquid microextraction (DLLME) technique is widely recognized as the most effective approach for enhancing overall detection sensitivity. While various DLLME modes have been advanced in pharmaceutical analysis, there need to be more discussions on pre-concentration techniques specifically developed for this field. This review presents a comprehensive overview of the different DLLME modes used in pharmaceutical analysis from 2017 to May 2023. The review covers the principles of DLLME, the factors affecting microextraction, the selected applications of different DLLME modes, and their advantages and disadvantages. Additionally, it focuses on multi-extraction strategies employed for pharmaceutical analysis.

Detection, quantification and degradation kinetic for five benzodiazepines using VAUS-ME-SFO/LC-MS/MS method for water, alcoholic and non-alcoholic beverages

Benzodiazepines can make victims more docile, they are frequently used in drug-facilitated crimes, such as robberies and sexual assaults. Therefore, it is essential to develop techniques for determining whether these chemicals are present in relation with illegal activity is crucial. Therefore, to determine the presence of five benzodiazepines (alprazolam, clonazepam, diazepam, lorazepam, and oxazepam) in water, alcoholic beverages, and non-alcoholic beverages, a simple and direct, miniaturized, and effective vortex assisted ultrasound based microextraction using solidification of floating organic droplets (VAUS-ME-SFO) in combination with LC-MS/MS was developed. 1-Undecanol and acetonitrile, respectively, served as the extractant and disperser solvents. Many other parameters affect the efficiency of the developed analytical procedure VAUS-ME-SFO/LC-MS/MS. These parameters were optimized using Plackett Burman Design and Central Composite Design to obtain reliable results. The optimum conditions for the extraction were: 10.0 mL of sample; 180 μL acetonitrile, as a dispersive solvent; 200 μL of 1-undecanol, as an extraction solvent; pH 7; 105 s of vortex agitation; 120 s of ultrasonication application and 3 min of centrifugation at 7000 rpm. The benzodiazepines were separated by a chromatographic separation technique carried out by a UPLC system consisting of a binary mobile phase. The solvent system comprises of 0.1% Formic acid in Milli-Q (Solvent A) and 0.1% Formic acid in ACN (Solvent B) with a gradient flow of 3.5 min total analysis time. Under the optimized conditions, the calibration curve was studied in the range of 0.124-7.810 ng mL^-1. The regression correlation coefficient (R²) value of all targeted analytes ranges from 0.993 to 0.999. The LOD and LOQ of VAUS-ME-SFO methods using LC-MS/MS analysis range from 0.316 to 0.968 ng mL^-1 and 1.055-3.277 ng mL^-1 respectively. The repeatability within a day varied from 0.6 to 3.5%, and the reproducibility across days varied from 2.2 to 6.3%. The recoveries ranges for water, alcoholic and non-alcoholic beverages from 70.77 to 114.53%, 63.20-102.21% and 66.23-113.28% respectively. Further, the degradation kinetics was studied to establish the half-life of each targeted analyte in the matrix undertaken in the study. The water samples were classified based on their BDZs residues. This implies that the more health care and anthropogenic activity, the more the BDZs residue will be in water samples.

Alprazolam Detection Using an Electrochemical Nanobiosensor Based on AuNUs/Fe-Ni@rGO Nanocomposite

Despite all the psychological advantages of alprazolam, its long list of toxic properties and interactions has caused concern and highlighted the need for a reliable sensing method. In this study, we developed a simple, highly sensitive electrochemical nanobiosensor to determine the desirable dose of alprazolam, averting the undesirable consequences of overdose. Gold nanourchins (AuNUs) and iron-nickel reduced graphene oxide (Fe-Ni@rGO) were immobilized on a glassy carbon electrode, which was treated beforehand. The electrode surface was characterized using cyclic voltammetry, Fourier transform infrared spectroscopy, scanning electron microscopy/energy-dispersive X-ray spectroscopy, and differential pulse voltammetry. The fabricated sensor showed two linear ranges (4 to 500 µg L^-1 and 1 to 50 mg L^-1), low limit of detection (1 µg L^-1), high sensitivity, good repeatability, and good recovery. Increased -OH and carboxyl (-COOH) groups on the electrode surface, resulting in improved the adsorption of alprazolam and thus lower limit of detection. This nanobiosensor could detect alprazolam powder dissolved in diluted blood serum; we also studied other benzodiazepine drugs (clonazepam, oxazepam, and diazepam) with this nanobiosensor, and results were sensible, with a significant difference.

[Determination of five nitroimidazoles and six benzodiazepines in aquatic products using ultra-high performance liquid chromatography-tandem mass spectrometry coupled with dispersive solid-phase extraction]

Nitroimidazoles (NMZs) are a crucial group of antibacterial compounds from a historical perspective. In the past, they were used for treating and preventing parasitic infections in fish. Benzodiazepines (BZDs) are second-generation sedative-hypnotics. Some fish farmers or vendors use them illegally to keep aquatic products fresh during the transportation of aquatic animals. Aquatic products are one of the most common food sources of protein and can be contaminated by NMZs and BZDs, which could impact humans through the food chain. Until recently, there was limited information on the simultaneous determination of NMZs and BZDs. Thus, it is critical to accurately quantify NMZs and BZDs for risk assessment and risk monitoring of food safety. For the simultaneous determination of five nitroimidazoles and six benzodiazepines in aquatic products, a new approach based on the dispersive solid-phase extraction (dSPE) coupled with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was developed. First, the samples were extracted with acetonitrile containing 1% (v/v) ammonium hydroxide, and the extracts were purified using dSPE with C18 and primary secondary amine sorbents. Second, the extracts were collected and dried at 45 ℃ under nitrogen flow. Finally, the extracts were redissolved in 1 mL methanol-water (1∶9, v/v) mixture, filtered through a nylon-66 microfiltration membrane, and analyzed using UHPLC-MS/MS. The separation of compounds was conducted on a Kinetex F5 column (100 mm×3.0 mm, 2.6 μm) using gradient elution with 1% (v/v) formic acid aqueous solution and methanol as the mobile phase. The analytes were detected using MS/MS with positive electrospray ionization (ESI+) source under the multiple reaction monitoring modes. The matrix-matched external standard approach was used for quantitative analysis. The compounds of five nitroimidazoles and six benzodiazepines could be examined within 8.5 min. Under the optimal conditions, the standard curves were linear in the range of 0.5-20 μg/L, with the correlation coefficients exceeding 0.995. The limits of detection and limits of quantification were 0.2-0.5 μg/kg and 0.5-1.0 μg/kg, respectively. The average recoveries at three spiked levels in blank samples (grass carp, large yellow croaker, and prawn) ranged from 73.2% to 110.6%, with relative standard deviations of less than 15%. The developed approach is simple, sensitive, fast, and inexpensive. It can be used for determining five nitroimidazoles and six benzodiazepines in aquatic products.

Vortex-assisted dispersive liquid-liquid microextraction-gas chromatography (VADLLME-GC) determination of residual ketamine, nimetazepam, and xylazine from drug-spiked beverages appearing in liquid, droplet, and dry forms

Presently, investigations of drug-facilitated crimes (DFCs) rely on the detection of substances extracted from biological samples following intake by the victim. However, such detection requires rapid sampling and analysis prior to metabolism and elimination of the drugs from the body. In cases of suspected DFCs, drug-spiked beverage samples, whether in liquid, droplet, or even dried form, can be tested for the presence of spike drugs and used as evidence for the occurrence of DFCs. This study aimed to quantitatively determine three sedative-hypnotics (ketamine, nimetazepam, and xylazine) from drug-spiked beverages using a vortex-assisted dispersive liquid-liquid microextraction-gas chromatography (VADLLME-GC) approach. In this study, a GC method was first developed and validated, followed by the optimization of the VADLLME protocol, which was then applied to quantify the target substances in simulated forensic case scenarios. The developed GC method was selective, sensitive (limit of detection: 0.08 μg/ml [ketamine]; 0.16 μg/ml [nimetazepam]; 0.08 μg/ml [xylazine]), linear (R²  > 0.99), precise (%RSD <7.2%), and accurate (% recovery: 92.8%-103.5%). Higher recoveries were achieved for the three drugs from beverage samples in liquid form (51%-97%) as compared to droplet (48%-96%) and dried (44%-93%) residues. The recovery was not hindered by very low volumes of spiked beverage and dried residues. In conclusion, the developed VADLLME-GC method successfully recovered ketamine, nimetazepam, and xylazine from spiked beverages that are likely to be encountered during forensic investigation of DFCs.

[Research progress of microextraction by packed sorbent and its application in microvolume sample extraction]

Microextraction is a rapidly developing sample preparation technology in the field of analytical chemistry, which is seeing widespread application. Accurate sample preparation can not only save time but also improve the efficiency of analysis, determination, and data quality. At present, sample pretreatment methods must be rapid, allow for miniaturization, automation, and convenient online connection with analytical instruments. To meet the requirements of green analytical methods and improve the extraction efficiency, microextraction techniques have been introduced as suitable replacements to conventional sample preparation and extraction methods. Microextraction using a packed sorbent (MEPS) is a new type of sample preparation technology. The MEPS equipment was prepared using microsyringe with a volume of 50-500 μL, including MEPS syringes and MEPS adsorption beds (barrel insert and needle, BIN), which is essentially similar to a miniaturized solid phase extraction device. The BIN contains the adsorbent and is built into the syringe needle. A typical MEPS extraction procedure involves repeatedly pumping the sample solution in two directions (up and down) through the adsorbent multiple times in the MEPS syringe. The specific operation course of MEPS includes conditioning, loading, washing, elution, and introduction into the analysis instrument. The conditioning process is adopted to infiltrate the dry sorbent and remove bubbles between the filler particles. The adsorption process is accomplished by pulling the liquid plunger of the syringe so that the sample flows through the adsorbent in both directions multiple times. The washing process involves rinsing the sorbent to remove unwanted components after the analyte is retained. The elution process involves the use of an eluent to ensure that the sample flows through the adsorbent in both directions multiple times, so that elution can be realized by the pumping-pushing action. The target analyte is eluted with the eluent, which can be directly used for chromatographic analysis. However, when processing complex biological matrix samples by MEPS, pretreatment steps such as dilution of the sample and removal of proteins are commonly required. At present, the operation modes of the MEPS equipment are classified into three types: manual, semi-automated, and fully automated. This increase in the degree of automation is highly conducive to processing extremely low or extremely high sample volumes. Critical factors affecting the MEPS performance have been investigated in this study. The conditions for MEPS optimization are the operating process parameters, including sample flow rate, sample volume, number of sample extraction cycles, type and volume of the adsorbent, and elution solvents. It is also necessary to consider the effect of the sample matrix on the performance of MEPS. The MEPS sorbent should be cleaned by a solvent to eliminate carryover and reuse. The sorbent is a core aspect of MEPS. Several types of commercial and non-commercial sorbents have been used in MEPS. Commercial sorbents include silica-based sorbents such as unmodified silica (SIL), C2, C8, and C18. Unmodified silicon-based silica is a normal phase adsorption material, which is highly polar and can be used to retain polar analytes. C18, C8, and C2 materials are suitable for reversed-phase adsorption, while SCX, SAX, APS, and M1 (C8+SCX) adsorbents are suitable for the mixed-mode and ion-exchange modes. Noncommercial sorbents include molecularly imprinted materials, restricted-access molecularly imprinted materials, graphitized carbon, conductive polymer materials, modified silicon materials, and covalent-organic framework materials. The performance of MEPS has recently been illustrated by online with LC-MS and GC-MS assays for the analysis of biological matrices, environmental samples, and food samples. Pretreatment in MEPS protocols includes dilution, protein precipitation, and centrifugation in biological fluid matrices. Because of the small sample size, fast operation, etc., MEPS is expected to be more widely used in the analysis of bio-matrix samples. MEPS devices could also play an important role in field pretreatment and analysis.

Interpol review of controlled substances 2016-2019

This review paper covers the forensic-relevant literature in controlled substances from 2016 to 2019 as a part of the 19th Interpol International Forensic Science Managers Symposium. The review papers are also available at the Interpol website at: https://www.interpol.int/content/download/14458/file/Interpol%20Review%20Papers%202019.pdf.

Voltammetric Electronic Tongue for the Simultaneous Determination of Three Benzodiazepines

The presented manuscript reports the simultaneous detection of a ternary mixture of the benzodiazepines diazepam, lorazepam, and flunitrazepam using an array of voltammetric sensors and the electronic tongue principle. The electrodes used in the array were selected from a set of differently modified graphite epoxy composite electrodes; specifically, six electrodes were used incorporating metallic nanoparticles of Cu and Pt, oxide nanoparticles of CuO and WO₃, plus pristine electrodes of epoxy-graphite and metallic Pt disk. Cyclic voltammetry was the technique used to obtain the voltammetric responses. Multivariate examination using Principal Component Analysis (PCA) justified the choice of sensors in order to get the proper discrimination of the benzodiazepines. Next, a quantitative model to predict the concentrations of mixtures of the three benzodiazepines was built employing the set of voltammograms, and was first processed with the Discrete Wavelet Transform, which fed an artificial neural network response model. The developed model successfully predicted the concentration of the three compounds with a normalized root mean square error (NRMSE) of 0.034 and 0.106 for the training and test subsets, respectively, and coefficient of correlation R ≥ 0.938 in the predicted vs. expected concentrations comparison graph.

Rapid detection of hypnotics using surface-enhanced Raman scattering based on gold nanoparticle co-aggregation in a wet system

Sensitive detection of drugs using a method with high qualification capability is important for forensic drug analysis. Vibrational spectroscopy is a powerful screening technique because it can provide detailed structural information of the compounds included in samples with simple experimental protocols. Among various spectroscopic techniques, surface enhanced Raman scattering (SERS) spectroscopy has attracted enormous attention owing to its ultra-high sensitivity. In this study, we developed a method for rapid detection of hypnotics using SERS with gold nanoparticle co-aggregation in a wet system. The developed method required a simple analytical protocol. This enabled rapid analysis with high stability and repeatability. We analyzed various hypnotics (19 types including benzodiazepines and nonbenzodiazepines) to investigate the structure-spectrum relationship. As a proof of concept for application to real crime samples, simulated spiked beverages containing one hypnotic (etizolam, flunitrazepam, zolpidem, or zopiclone) were analyzed. Diluting the beverage samples decreased the matrix effect and allowed for detection of these hypnotics. Except for flunitrazepam, strong signals were observed for all hypnotics, and the estimated lower limit of detection was 50 ppm in apple drink. The developed approach is a rapid method for screening analysis of hypnotics with low sample requirements.

Current trends on microextraction by packed sorbent – fundamentals, application fields, innovative improvements and future applications

MEPS, the acronym of microextraction by packed sorbent, is a simple, fast and user- and environmentally-friendly miniaturization of the popular solid-phase extraction technique (SPE).

Analytical Methods Used for the Detection and Quantification of Benzodiazepines

The prescription of psychotropic drugs, especially benzodiazepines (BZDs), occupies a preponderant place in the management of mental illnesses. Indeed, the BZDs have been used in different therapeutic areas including insomnia, anxiety, seizure disorders, or general anesthesia. Unfortunately, these drugs are present in the illegal street market, leading to a lot of drug abuse amongst some addicted users, road insecurity, and suicide. Hence, it has become essential to analyze the BZDs drugs in human biological specimens for drug abuse in forensic sciences. The present review provides a summary of sample preparation techniques (solid-phase extraction and Liquid-liquid phase extraction) and the methods for the detection and quantification of BZDs molecules in the commonly used biological specimens over the ten last years which may potentially lead to better and accurate evaluation of the physiological state of a given person. The commonly used methods for the detection and quantification of BZDs include nuclear magnetic resonance (NMR), chromatography (GC-MS, HPLC, and TLC), immunoassay (ELISA, RIA, LFA, CEDEA, FPIA, and KIMS), and electroanalytical methods (voltammetry and potentiometry).