Optimisation and characterisation of marihuana extracts obtained by supercritical fluid extraction and focused ultrasound extraction and retention time locking GC‐MS

The optimisation of focused ultrasound extraction and supercritical fluid extraction of volatile oils and cannabinoids from marihuana has been accomplished by experimental design approach. On the one hand, the focused ultrasound extraction method of volatile compounds and cannabinoids was studied based on the optimisation of cyclohexane and isopropanol solvent mixtures, and the instrumental variables. The optimal working conditions were finally fixed at isopropanol/cyclohexane 1:1 mixture, cycles (3 s^?1), amplitude (80%) and sonication time (5 min). On the other hand, the supercritical fluid extraction method was optimised in order to obtain a deterpenation of the plant and a subsequent cannabinoid extraction. For this purpose, pressure, temperature, flow and co‐solvent percentage were optimised and the optimal working conditions were set at 100 bar, 35°C, 1 mL/min, no co‐solvent for the terpenes and 20% of ethanol for the cannabinoids. Based on the retention time locking GC‐MS analysis of the supercritical fluid extracts the classification of the samples according to the type of plant, the growing area and season was attained. Finally, three monoterpenes and three cannabinoids were quantified in the ranges of 0.006–6.2 μg/g and 0.96–324 mg/g, respectively.     

Comprehensive classification of USA cannabis samples based on chemical profiles of major cannabinoids and terpenoids

Abstract

Different USA-origin cannabis samples were analyzed by GC-FID to quantify all possible cannabinoids and terpenoids prior to their clustering. Chromatographic analysis confirmed the presence of seven cannabinoids and sixteen terpenoids with variable levels. Among tested cannabinoids, Δ⁹-Tetrahydrocannabinol Δ⁹-THC and cannabinol CBN were available in excess amounts (1.2–8.0?wt%) and (0.22–1.1?wt%), respectively. Fenchol was the most abundant terpenoid with a range of (0.03–1.0?wt%). The measured chemical profile was used to cluster 23 USA states and to group plant samples using different unsupervised multivariate statistical tools. Clustering of plant samples and states was sensitive to the selected cannabinoids/terpenoids. Principal component analysis (PCA) indicated the importance of Δ⁹-THC, CBN, CBG, CBC, THCV, Δ⁸-THC, CBL, and fenchol for samples clustering. Δ⁹-THC was significant to separate California-origin samples while CBN and fenchol were dominant to separate Oregon-origin samples away from the rest of cannabis samples. A special PCA analysis was performed on cannabinoids after excluding Δ⁹-THC (due to its high variability in the same plant) and CBN (as a degradation byproduct for THC). Results indicated that CBL and Δ⁸-THC were necessary to separate Nevada and Washington samples, while, CBC was necessary to isolate Oregon and Illinois plant samples. PCA based on terpenoids content confirmed the significance of caryophyllene, guaiol, limonene, linalool, and fenchol for clustering target. Fenchol played a major role for clustering plant samples that originated from Washington and Nevada. k-means method was more flexible than PCA and generated three different classes; samples obtained from Oregon and California in comparison to the rest of other samples were obviously separated alone, which attributed to their unique chemical profile. Finally, both PCA and k-means were useful and quick guides for cannabis clustering based on their chemical profile. Thus, less effort, time, and materials will be consumed in addition to decreasing operational conditions for cannabis clustering.     

A Rapid Nano-Liquid Chromatographic Method for the Analysis of Cannabinoids in Cannabis sativa L. Extracts

Cannabis sativa L. is an herbaceous plant belonging to the family of Cannabaceae. It is classified into three different chemotypes based on the different cannabinoids profile. In particular, fiber-type cannabis (hemp) is rich in cannabidiol (CBD) content. In the present work, a rapid nano liquid chromatographic method (nano-LC) was proposed for the determination of the main cannabinoids in Cannabis sativa L. (hemp) inflorescences belonging to different varieties. The nano-LC experiments were carried out in a 100 µm internal diameter capillary column packed with a C18 stationary phase for 15 cm with a mobile phase composed of ACN/H₂O/formic acid, 80/19/1% (v/v/v). The reverse-phase nano-LC method allowed the complete separation of four standard cannabinoids in less than 12 min under isocratic elution mode. The nano-LC method coupled to ultraviolet (UV) detection was validated and applied to the quantification of the target analytes in cannabis extracts. The nano-LC system was also coupled to an electrospray ionization–mass spectrometry (ESI-MS) detector to confirm the identity of the cannabinoids present in hemp samples. For the extraction of the cannabinoids, three different approaches, including dynamic maceration (DM), ultrasound-assisted extraction (UAE), and an extraction procedure adapted from the French Pharmacopeia’s protocol on medicinal plants, were carried out, and the results achieved were compared.     

Analysis of 30 synthetic cannabinoids in serum by liquid chromatography‐electrospray ionization tandem mass spectrometry after liquid‐liquid extraction

The analysis of synthetic cannabinoids in human matrices is of particular importance in the fields of forensic and clinical toxicology since cannabis users partly shift to the consumption of ‘herbal mixtures’ as a legal alternative to cannabis products in order to circumvent drug testing. However, comprehensive methods covering the majority of synthetic cannabinoids already identified on the drug market are still lacking. In this article, we present a fully validated method for the analysis of 30 synthetic cannabinoids in human serum utilizing liquid‐liquid extraction and liquid chromatography‐electrospray ionization tandem mass spectrometry. The method proved to be suitable for the quantification of 27 substances. The limits of detection ranged from 0.01 to 2.0 ng/mL, whereas the lower limits of quantification were in the range from 0.1 to 2.0 ng/mL. The presented method was successfully applied to 833 authentic serum samples during routine analysis between August 2011 and January 2012. A total of 227 (27%) samples was tested positive for at least one of the following synthetic cannabinoids: JWH‐018, JWH‐019, JWH‐073, JWH‐081, JWH‐122, JWH‐200, JWH‐203, JWH‐210, JWH‐307, AM‐2201 and RCS‐4. The most prevalent compounds in positive samples were JWH‐210 (80%), JWH‐122 (63%) as well as AM‐2201 (29%). Median serum concentrations were all below 1.0 ng/mL. These findings demonstrate a significant shift of the market of synthetic cannabinoids towards substances featuring a higher CB₁ binding affinity and clearly emphasize that the analysis of synthetic cannabinoids in serum or blood samples requires highly sensitive analytical methods covering a wide spectrum of substances. Copyright © 2012 John Wiley & Sons, Ltd.     

A comprehensive library‐based,automated screening procedure for 46 synthetic cannabinoids in serum employing liquid chromatography‐quadrupole ion trap mass spectrometry with high‐temperature electrospray ionization

Considering the vast variety of synthetic cannabinoids and herbal mixtures – commonly known as ‘Spice’ or ‘K2’ – on the market and the resulting increase of severe intoxications related to their consumption, there is a need in clinical and forensic toxicology for comprehensive up‐to‐date screening methods. The focus of this project aimed at developing and implementing an automated screening procedure for the detection of synthetic cannabinoids in serum using a liquid chromatography‐ion trap‐MS (LC‐MSⁿ) system and a spectra library‐based approach, currently including 46 synthetic cannabinoids and 8 isotope labelled analogues. In the process of method development, a high‐temperature ESI source (IonBooster^TM, Bruker Daltonik) and its effects on the ionization efficiency of the investigated synthetic cannabinoids were evaluated and compared to a conventional ESI source. Despite their structural diversity, all investigated synthetic cannabinoids benefitted from high‐temperature ionization by showing remarkably higher MS intensities compared to conventional ESI. The employed search algorithm matches retention time, MS and MS²/MS³ spectra. With the utilization of the ionBooster source, limits for the automated detection comparable to cut‐off values of routine MRM methods were achieved for the majority of analytes. Even compounds not identified when using a conventional ESI source were detected using the ionBooster‐source. LODs in serum range from 0.1 ng/ml to 0.5 ng/ml. The use of parent compounds as analytical targets offers the possibility of instantly adding new emerging compounds to the library and immediately applying the updated method to serum samples, allowing the rapid adaptation of the screening method to ongoing forensic or clinical requirements. The presented approach can also be applied to other specimens, such as oral fluid or hair, and herbal mixtures and was successfully applied to authentic serum samples. Quantitative MRM results of samples with analyte concentrations above the determined LOD were confirmed as positive findings by the presented method. Copyright © 2014 John Wiley & Sons, Ltd.     

Headspace solid-phase microextraction of cannabinoids in human head hair samples

A fast method was optimized and validated with the aim to detect cannabinoids (cannabidiol, cannabinol, and delta-9-tetrahydrocannabinol) in human head hair samples. The method was based on an initial procedure of external decontamination of hair samples (10 mg) with petroleum ether, followed by alkaline digestion and further extraction of cannabinoids by means of a headspace solid-phase microextraction technique (HS-SPME). GC-MS was used to identify and quantify the analytes in SIM mode. The LOQs and LODs obtained were 0.07 and 0.12 ng/mg, respectively, for all the studied cannabinoids. The method proved to be simple, rapid, and precise. By using the weighted least squares linear regression (weighting factor 1/x2), the accuracy of the analytical method was improved at the lower end of the calibration curve (from 0.12 to 12 ng/mg; r >0.98). Hair samples collected from eight volunteers (in-patients of a drug abuse rehabilitation clinic) were submitted to the proposed method. Detection of the drugs was observed in samples of the volunteers who reported frequent marijuana use (at least ten times a week).     

A high-sensitivity ultra-high performance liquid chromatography/high-resolution time-of-flight mass spectrometry (UHPLC-HR-TOFMS) method for screening synthetic cannabinoids and other drugs of abuse in urine

The continuing emergence of designer drugs imposes high demands on the scope and sensitivity of toxicological drug screening procedures. An ultra-high performance liquid chromatography/high-resolution time-of-flight mass spectrometry (UHPLC-HR-TOFMS) method was developed for screening and simultaneous confirmation of both designer drugs and other drugs of abuse in urine samples in a single run. The method covered selected synthetic cannabinoids and cathinones, amphetamines, natural cannabinoids, opioids, cocaine and other important drugs of abuse, together with their main urinary metabolites. The database consisted of 277 compounds with molecular formula and exact monoisotopic mass; retention time was included for 192 compounds, and primary and secondary qualifier ion exact mass for 191 and 95 compounds, respectively. Following a solid-phase extraction, separation was performed by UHPLC and mass analysis by HR-TOFMS. MS, and broad-band collision-induced dissociation data were acquired at m/z range 50–700. Compound identification was based on a reverse database search with acceptance criteria for retention time, precursor ion mass accuracy, isotopic pattern and abundance of qualifier ions. Mass resolving power in spiked urine samples was on average FWHM 23,500 and mass accuracy 0.3 mDa. The mean and median cut-off concentrations determined for 75 compounds were 4.2 and 1 ng/mL, respectively. The range of cut-off concentrations for synthetic cannabinoids was 0.2–60 ng/mL and for cathinones 0.7–15 ng/mL. The method proved to combine high sensitivity and a wide scope in a manner not previously reported in drugs of abuse screening. The method’s feasibility was demonstrated with 50 authentic urine samples.

Determination of triazine herbicides in sheep liver by microwave-assisted extraction and high performance liquid chromatography

A multi-residue method developed for the analysis of triazine herbicides, simazine, atrazine, propazine and prometryne, in sheep liver is presented. The method is based on microwave-assisted extraction (MAE) of sheep liver using methanol as extractant and analysis of extracts by high performance liquid chromatography (HPLC) and ultraviolet detection. MAE operational parameters, the solvent type and volume, extraction temperature and time, were optimized in detail with respect to extraction efficiency of the target compounds from sheep liver. The recoveries of the method at two different spiked levels were assessed by analyzing spiked liver samples and were found to be in the range from 90 to 102% with good precision (<11%).     

Determination of phthalate esters in liquor samples by vortex‐assisted surfactant‐enhanced‐emulsification liquid–liquid microextraction followed by GC–MS

A novel method using vortex‐assisted surfactant‐enhanced‐emulsification liquid–liquid microextraction has been developed for the extraction of phthalate esters (PAEs) in Chinese liquor samples prior to analysis by GC–MS. In the proposed method, a high‐density extraction solvent (carbon tetrachloride) was dispersed into samples with the aid of a surfactant (Triton X‐100) and vortex agitation, resulting in a short extraction equilibrium (30 s). After centrifugation, a single microdrop of solvent was easily collected for GC–MS analysis. Key factors that affected the extraction efficiency were optimized. Under the optimum conditions, linearity was found in the range from 0.05 to 50 μg/L. Coefficients of determination varied from 0.9938 to 0.9971. LODs, based on an S/N of 3, ranged from 4.9 to 13 ng/L. Enrichment factors varied from 140 to 184. Reproducibility and recoveries were assessed by testing a series of three liquor samples that were spiked with different concentration levels. Finally, the proposed method was successfully applied to the determination of PAEs in 16 Chinese liquor samples. In this work, high‐density‐solvent vortex‐assisted surfactant‐enhanced‐emulsification liquid–liquid microextraction was applied for the first time for the extraction of PAEs in Chinese liquor samples and was proved to be simple, rapid, and sensitive.     

Analysis of furan in foods by headspace solid-phase microextraction-gas chromatography-ion trap mass spectrometry

A headspace-solid-phase microextraction (HS-SPME) coupled to gas chromatography-ion trap mass spectrometry (GC-IT-MS) method is proposed for the analysis of furan in different heat-treated carbohydrate-rich food samples. The extraction efficiency of six commercially available fibres was evaluated and it was found that a 75mum carboxen/polydimethylsiloxane coating was the most suitable for the extraction of the furan. Parameters affecting the efficiency of HS-SPME procedure such as extraction temperature and time, ionic strength, headspace and aqueous volume ratio (V(h)/V(w)), desorption temperature and time, were optimized. Quality parameters were established using spiked water and food samples. Linearity ranged between 0.02 and 0.5ngg(-1) and run-to-run and day-to-day precisions for food samples were lower than 6% and 10%, respectively. The limit of detection (LOD) of the method is sample dependent and ranged from 8 to 70pgg(-1), while the limit of quantification is from 30 to 250pgg(-1). Isotope dilution using furan-d(4) is proposed for furan determination providing similar results to those obtained by standard addition with internal standard (US Food and Drug Administration method). The developed HS-SPME-GC-IT-MS method was applied to the analysis of furan in different Spanish food samples from a local market, and concentrations ranging from 0.17 to 2279ngg(-1) were found.     

Determination of polycyclic aromatic hydrocarbons in water by a novel mesoporous‐coated stainless steel wire microextraction combined with HPLC

A novel mesoporous‐coated stainless steel wire microextraction coupled with the HPLC procedure for quantification of four polycyclic aromatic hydrocarbons in water has been developed, based on the sorption of target analytes on a selectively adsorptive fiber and subsequent desorption of analytes directly into HPLC. Phenyl‐functionalized mesoporous materials (Ph‐SBA‐15) were synthesized and coated on the surfaces of a stainless steel wire. Due to the high porosity and large surface area of the Ph‐SBA‐15, high extraction efficiency is expected. The influence of various parameters on polycyclic aromatic hydrocarbons extraction efficiency were thoroughly studied and optimized (such as the extraction temperature, the extraction time, the desorption time, the stirring rate and the ionic strength of samples). The results showed that each compound for the analysis of real water samples was tested under optimal conditions with the linearity ranging from 1.02×10^?3 to 200 μg/ L and the detection limits were found from 0.32 to 2.44 ng/ L, respectively. The RSD of the new method was smaller than 4.10%.     

Conversion Characteristics of Some Major Cannabinoids from Hemp (Cannabis sativa L.) Raw Materials by New Rapid Simultaneous Analysis Method

This study was carried out to develop a high-performance liquid chromatography method for short-time analysis of the main cannabinoids in the inflorescence of hemp (Cannabis sativa L.). We also performed decarboxylation of the raw material using our advanced analysis technique. In this study, the UV spectrum was considered to analyze each of the four common cannabinoids, solvents, and samples, where the uniform elution of acidic cannabinoids without peak tailing and acids was tested. Optimal results were obtained when readings were taken at a wavelength of 220 nm using water and methanol containing trifluoroacetic acid as mobile phases in a solvent gradient system. The established conditions were further validated by system suitability, linearity, precision, detection limit, and quantitation limit tests. The decarboxylation index (DT₅₀) confirmed that Δ9-THCA decarboxylated faster than CBDA, and both maintained a linear relationship with time and temperature. In addition, the loss of cannabidiol was better prevented during the decarboxylation process in the natural state than in the extracted state.     

离子色谱法测定盐湖沉积物中可溶性阴离子

盐湖沉积物中可溶性阴离子提取和测试方法对其实验结果至关重要,但不同的前处理提取和测试条件缺乏系统的对比和优化。本文对比了水浴加热、超声提取、涡旋震荡三种前处理条件的提取效率,发现涡旋震荡离心的前处理方法回收率最佳,并进一步优化了水土比例、涡旋震荡离心方法的浸提时间和浸提次数。在离子色谱测试方法方面,发现以30 mmol/L KOH溶液作为淋洗液,流速1 mL/min,柱温30 oC,电导检测器进行离子色谱分析效果最好。最终建立了以涡旋震荡离心为前处理提取,离子色谱法测定盐湖沉积物中四种无机可溶性阴离子（F-、Cl-、SO42-和NO3-）的检测方法。该方法中,四种阴离子检出限≤0.026 mg/L,线性相关性良好R2≥0.998,加标回收率为80%~114%,精密度RSD为0.64%~1.31%,具有快速准确、灵敏度高、简单可靠等优点,可适用于高盐度盐湖沉积物样品中无机阴离子的测定,并利用该方法对六份西藏地区盐湖表层沉积物样品进行分析。     

Pressurized-fluid extraction (PFE) of chlorinated paraffins from the biodegradable fraction of source-separated household waste

A method is presented in which pressurized-fluid extraction (PFE) is used for the extraction of chlorinated paraffins (CP) from the biodegradable fraction of source-separated household waste. The conditions that were optimized for high recovery in the extraction procedure were extraction time, temperature, and the use of different solvents and different sample particle sizes, Recoveries of CP from fortified household waste material were over 90%, with only few interferences when cyclohexane was used as solvent. Extraction yields from contaminated samples containing CP were further compared with recoveries obtained by use of Soxtec extraction. The results showed that PFE is a rapid, low-solvent-consuming technique, giving high yields.     

Development of a sample preparation procedure of sewage sludge samples for the determination of polycyclic aromatic hydrocarbons based on selective pressurized liquid extraction

An automated, simple and sensitive method based on selective pressurized liquid extraction (SPLE) was developed for the analysis of polycyclic aromatic hydrocarbons in sewage sludge samples. The new sample preparation procedure consists of on-line clean-up by inclusion of sorbents in the extraction cell, and combines elevated temperatures and pressures with liquid solvents to achieve fast and efficient removal of target analytes from complex sewage sludge matrices. The effects of various operational parameters (e.g. sample pretreatment, extraction solvent, temperature, pressure, static time, etc.) on the performance of SPLE procedure were carefully investigated, obtaining the best results when SPLE conditions were fixed at 140 °C, 1500 psi, static time of 5 min and n-hexane as extraction solvent. A new programmed temperature vaporization–gas chromatography–tandem mass spectrometry method based on large volume injection (PTV–LVI–GC–MS/MS) was also developed and analytical determinations were performed by high performance liquid chromatography coupled with fluorescence detection and GC–MS/MS. The extraction yields for the different compounds obtained by SPLE ranged from 84.8% to 106.6%. Quantification limits obtained for all of these studied compounds (between 0.0001 and 0.005 μg g⁻¹, dry mass) were well below the regulatory limits for all compounds considered. To test the accuracy of the SPLE technique, the optimized methodology was applied to the analysis of a certified reference material (sewage sludge (BCR088)) and a reference material (sewage sludge (RTC-CNS312-04)), with excellent results.     

In Situ Decarboxylation-Pressurized Hot Water Extraction for Selective Extraction of Cannabinoids from Cannabis sativa. Chemometric Approach

Isolation of the therapeutic cannabinoid compounds from Cannabis Sativa L. (C. Sativa) is important for the development of cannabis-based pharmaceuticals for cancer treatment, among other ailments. The main pharmacological cannabinoids are THC and CBD. However, THC also induces undesirable psychoactive effects. The decarboxylation process converts the naturally occurring acidic forms of cannabinoids, such as cannabidiolic acid (CBDA) and tetrahydrocannabinolic acid (THCA), to their more active neutral forms, known as cannabidiol (CBD) and tetrahydrocannabinol (THC). The purpose of this study was to selectively extract cannabinoids using a novel in situ decarboxylation pressurized hot water extraction (PHWE) system. The decarboxylation step was evaluated at different temperature (80–150 °C) and time (5–60 min) settings to obtain the optimal conditions for the decarboxylation-PHWE system using response surface methodology (RSM). The system was optimized to produce cannabis extracts with high CBD content, while suppressing the THC and CBN content. The identification and quantification of cannabinoid compounds were determined using UHPLC-MS/MS with external calibration. As a result, the RSM has shown good predictive capability with a p-value < 0.05, and the chosen parameters revealed to have a significant effect on the CBD, CBN and THC content. The optimal decarboxylation conditions for an extract richer in CBD than THC were set at 149.9 °C and 42 min as decarboxylation temperature and decarboxylation time, respectively. The extraction recoveries ranged between 96.56 and 103.42%, 95.22 and 99.95%, 99.62 and 99.81% for CBD, CBN and THC, respectively.     

Carbonized cotton fibers via a facile method for highly sensitive solid‐phase microextraction of polycyclic aromatic hydrocarbons

Cotton fiber is an environmentally friendly and natural material with a certain extraction capacity, while its enrichment ability is poor. In order to improve the extraction efficiency of cotton fibers, it was carbonized to form a layer of amorphous carbon as the sorbent by a simple carbonization method. Carbonized cotton fibers were filled into a polyetheretherketone tube for in‐tube solid‐phase microextraction. The carbonization time was investigated to obtain high extraction efficiency. Coupled to high‐performance liquid chromatography, the extraction tube was evaluated with polycyclic aromatic hydrocarbons, estrogens and phthalates, and it exhibited best extraction efficiency for polycyclic aromatic hydrocarbons. Under the optimum conditions, an online analysis method for several polycyclic aromatic hydrocarbons was established with large linear ranges (0.016–0.20 μg/L), low limits of detection (0.005–0.020 μg/L), and high enrichment factors (948–2874). Analysis method was successfully applied to the detection of targets in the real samples and shown satisfactory durability and chemical stability. Moreover, the relative recoveries ranged from 82 to 119.2%, which demonstrated the applicability of carbonized cotton fibers in sample preparation. Compared with other reported methods, the proposed method provided shorter extraction time, higher enrichment factors, comparable limits of detection, and recoveries.     

A needle trap device packed with MIL-100(Fe) metal organic frameworks for efficient headspace sampling and analysis of urinary BTEXs

The aim of this study was to develop a new method for the determination of benzene, toluene, ethylbenzene and xylene isomers (BTEXs) in urine samples. In this method, MIL-100(Fe)@Fe₃O₄@SiO₂ metal–organic framework was synthesized, characterized and packed inside a needle trap device (NTD) as a sorbent for headspace extraction of unmetabolized BTEXs from urine samples followed by gas chromatography (GC) analysis. The GC device was equipped with a flame ionization detector (FID). The results showed that the optimal extraction time, extraction temperature and salt content were 60 min, 30°C and 5%, respectively. Also, the optimal desorption time and temperature were determined to be 1 min and 250°C, respectively. The limits of detection and quantification of the analytes of interest were in the ranges 0.0001–0.0005 and 0.0003–0.0014 μg ml⁻¹, respectively. The intra- and inter-day repeatability were <7.6%. The accuracy of the measurements in urine samples was in the range 7.1–11.4%. The results also demonstrated that the proposed NTD offered various advantages such as having high sensitivity and being inexpensive, reusable, user friendly, environmentally friendly and compatible for use with the GC device. Therefore, it can be efficiently used as a MIL–NTD for the extraction and analysis of unmetabolized BTEXs from urine samples.     

Validated gas chromatographic-mass spectrometric analysis of urinary cannabinoids purified with a calcium-hardened beta-cyclodextrin polymer

A comprehensive solid-phase extraction (SPE) technique based on the formation of an inclusion complex between beta-cyclodextrin (betaCD) and cannabinoids including Delta(9)-tetrahydrocannabinol (THC), 11-hydroxy-Delta(9)-tetrahydrocannabinol (11-OH-THC) and 11-nor-9-carboxy-Delta(9)-tetrahydrocannabinol (THC-COOH) was developed in gas chromatographic-mass spectrometric (GC-MS) analysis. A betaCD/epichlorohydrin copolymer was prepared and then 'hardened' in aqueous solution with 0.3M CaCl(2) to yield a stable particulate copolymer, which was used as a novel SPE sorbent. An internal standard THC-COOH-d(9) was added to urine samples containing 3 cannabinoids and then purified with the hardened betaCD polymer. The cannabinoids were extracted from the hardened betaCD using tetrahydrofuran. Resulting extracts were evaporated and derivatized with MSTFA/NH(4)I/dithioerythritol (500:4:2, v/w/w) and analyzed by GC-MS in selected-ion monitoring (SIM) mode. Overall recoveries ranged from 85% to 102%, with a detection limit of 0.2mugL(-1) for the three cannabinoids tested. The precision (% CV) and accuracy (% bias) of the assay were 1.2-5.1% and 93-111% in 0.2-50mugL(-1) calibration range, respectively (r(2)>0.9997). Twenty actual samples positive by fluorescence polarization immunoassay were also quantitatively analyzed. The devised technique based on the calcium-hardened betaCD sorption of cannabinoids and subsequent GC-SIM/MS resulted in better selectivity and extraction efficiency than is possible using the conventional hydrophobicity-based SPE methods.     

Analysis of abuse drugs in urine using surfactant-assisted dispersive liquid-liquid microextraction

The process of surfactant-assisted dispersive liquid-liquid microextraction (SA-DLLME) followed by high-performance liquid chromatography-UV detection was successfully applied for the extraction and determination of selected cannabinoids (cannabidiol, Δ(9)-tetrahydrocannabinol, and cannabinol) in urine samples. The effective parameters on the extraction efficiency were studied and optimized utilizing two different optimization methods: one variable at a time (OVAT) and face center design (FCD). Under the optimum conditions (extraction solvent and its volume, toluene, 85 μL; disperser agent and its concentration, 1.0 mL of ultra-pure water containing 0.5 mmol/L tetradecyl tremethyl ammonium bromide (TTAB); sample pH, 2.0 and salt concentration, 11% w/v NaCl), the limits of detection of the method were in the range of 0.1-0.5 μg/L and the repeatability and reproducibility of the proposed method, expressed as relative deviation, varied between 4.1 and 8.5% and 6.7 and 11.6%, respectively. Linearity was found to be in the range of 1.0-200 μg/L and under the optimum conditions, the preconcentration factors (PFs) were between 190 and 292. This proposed method was successfully applied in the analysis of three male advocate urine samples and good recoveries were obtained.