Solvent Liquid Phase Microextraction Research Articles

Supramolecular Solvent Liquid Phase Microextraction of Voriconazole İn Pharmaceutical and Environmental Samples With High Performance Liquid Chromatography Detection

In this study, a new analytical method based on the supramolecular solvent liquid phase microextraction (Ss-LPME) and HPLC was developed for the analysis of voriconazole as an active drug in the class of antifungals with a wide spectrum of action at trace levels. Nano/micro sized supramolecular phase formed in 1-decanol, tetrahydrofuran and aqueous environment was used as extraction agent for separation and preconcentration of trace level of voriconazole. For the optimization of the Ss-LPME method, important analytical parameters such as the effect of sample solution pH, volume of 1-decanol, amount of THF, ultrasounic irridation time, centrifugation time and sample solution volume on the extraction efficiency were evaluated. Optimal conditions of the Ss-LPME; pH: 8, 1-decanol volume: 200 µL, THF volume: 300 µL, ultrasounic irridation time:10 min and centrifugation time: 8 min. For the developed Ss-LPME/HPLC procedure, the limit of detection (LOD), limit of quantification (LOQ) and enhancement factor (EF) were found 2.7 µg·L-1, 8.8 µg·L-1 and 36, respectively. The Ss-LPME/HPLC procedure was applied to waste water, lake water and drug samples. The fact that recovery values ranging from 100% to 108.5% were obtained for these real samples proved that this method can be used successfully in the matrix environments studied

The use of deep eutectic solvent-liquid phase microextraction as green analytical sample treatment for the analysis of drugs in urine

In this paper, a natural deep eutectic solvent (NADES)-based liquid phase microextraction (LPME) of 20 pharmaceuticals from urine, employing liquid chromatography tandem mass spectrometry (LC-MS/MS) for precise quantification, has been developed. The chromatographic gradient was accurately evaluated to ensure the effective separation of tramadol, an opioid receptor agonist, and o-desmethylvenlafaxine, one active metabolite of the antidepressant venlafaxine, both compounds sharing identical molecular mass for the precursor ion (Q1: 264.2 m/z) and fragmentation patterns (Quantifier ion: 58.2 m/z; qualifier ion: 246.0 m/z). NADES consisted of menthol-octanoic acid in a molar ratio of 1:2. Using the appropriate extraction conditions, the developed methodology provided appropriate LOQ values, ranging from 15 to 208 ng L–1, with reasonable RSD values (below 11 %), recoveries ranging from 64 to 120 % and preconcentration factors up to 66.6 folds. Application of the developed method to the analysis of urine samples served to highlight its usefulness. An AGREEprep score of 0.64 was obtained despite the demand for substantial sample volumes and the use of LC-MS/MS for analyte determination.

Deep eutectic solvent liquid phase microextraction, powered by ultrasonic system, for determination of β-carotene in food samples

The research work is mainly concerned with the extraction of β-carotene, which is a terpenoid compound, from food and fruit samples using deep eutectic solvent based liquid phase extraction. Deep eutectic solvent liquid phase microextraction method, powered by ultrasonic mixing, (DES-UP-LPME) was carried out with deep eutectic solvent (DES) consisting of tetrabutylammoniumbromide (TBAB) and decanoic acid (DA). Key parameters such as pH, sample volume, tetrahydrofuran (THF) volume, DES type and volume, matrix effect, ultrasonication/centrifugation time were optimized to increase the extraction efficiency of β-carotene. Quantitative recoveries were obtained when pH, TBAB:DA ratio and sample volume were 3, 1:3 and 30, respectively. The limit of detection (LOD) and limit of quantification (LOQ) were found to be 0.005 µg/mL and 0.015 µg/mL, respectively. Various food samples were analyzed spectrophotometrically by using the developed DES-UP-LPME at 450 nm. The addition/recovery studies were also performed on water samples to evaluate the accuracy of the method.

Vortex-assisted switchable solvent liquid-phase microextraction for preconcentration of cinnamic acid derivatives in traditional Chinese medicine

Vortex-assisted switchable solvent liquid-phase microextraction for preconcentration of cinnamic acid derivatives in traditional Chinese medicine

Hydrophilic deep eutectic solvent based microextraction procedure for the determination of four paraben preservatives in vitamin D for babies: A green approach

In this study, an easily available, sensitive, and fast hydrophilic deep eutectic solvent-liquid phase microextraction method developed using deep eutectic solvent (DES) as a green solvent for the determination and microextraction of paraben (methyl, ethyl, propyl, and butyl) preservatives in vitamin D for babies. The highest yield for extraction recovery was obtained using DES consisting of a 1:4 M ratio of choline chloride and acetic acid. Moreover, various optimization parameters such as DES volume, DES type, sample volume, and centrifugation time were investigated in order to develop a real sample specific microextraction method. Relative standard deviation values were 0.92%-2.87%, the detection limit was 0.194–0.254 µg/mL, and extraction recovery values were between 87.40% and 102.98%. The method developed in this study was successfully applied to 5 different babies in vitamin D for babies obtained from pharmacies for the determination of methyl, ethyl, propyl, and butylparaben. As far as we know, it is the first study conducted both in terms of the determination of paraben preservatives in vitamin D for babies and in terms of the fact that DES used in this study is used for the first time in vitamin D for babies.

Validation and green profile assessment of a binary solvent liquid phase microextraction method for the determination of chlorbenside and fenobucarb in lake and wastewater samples by GC-MS.

This study reports a liquid phase microextraction method based on binary extraction solvents, which were used to preconcentrate chlorbenside and fenobucarb from aqueous samples for determination by gas chromatography mass spectrometry. Parameters including the type, ratio, and volume of binary solvents, disperser solvent type and volume, and vortex period were optimized systematically to achieve high enrichment for the analytes. The optimum conditions obtained were used to validate the method, and the detection limits calculated for chlorbenside (0.71ng/mL) and fenobucarb (0.33ng/mL) correlated to enrichment factors of 399- and 912-folds, respectively. The optimum method was applied to lake water and wastewater samples in spike recovery experiments, and the results obtained (96-104%) verified the method as accurate and applicable to the aqueous sample matrices. Matrix matching calibration method was used to boost the accuracy of quantifying the two analytes in the wastewater sample, which presented interference effects. Assessment of the method's green profile based on penalty points confirmed the method's compliance with green analytical chemistry.

Optimization of vortex-assisted switchable hydrophilicity solvent liquid phase microextraction for the selective extraction of vanillin in different matrices prior to spectrophotometric analysis

The main purpose of this research article is to develop a vortex-assisted switchable hydrophilicity solvent liquid phase microextraction (VA-SHS-LPME) for the selective and efficient extraction of trace vanillin in food samples. Four switchable hydrophilicity solvents (SHSs) were prepared and tested for the extraction of vanillin. The obtained extract phase after phase separation was analyzed by UV–vis spectrophotometry. The extraction parameters including pH, vortex time, NaOH volume, and SHS volume were optimized using central composite design based on response surface methodology. Under optimized conditions, the linear range (0.2–400 ng mL−1 with r2 = 0.9985), limit of detection (0.06 ng mL−1), limit of quantitation (2.0 ng mL−1), extraction recovery (97 ± 4 %) and enhancement factor (220) were obtained. Also, relative standard deviations were less than 2.1 % indicating good precision. The VA-SHS-LPME procedure showed some advantages including good extraction, low consumption of chemical and low matrix effect. Finally, the VA-SHS-LPME procedure was applied for the determination of vanillin in food samples, and acceptable recoveries (91 ± 3–99 ± 3 %) were obtained.

Trace level determination of eleven nervous system-active pharmaceutical ingredients by switchable solvent-based liquid-phase microextraction and gas chromatography-mass spectrometry with matrix matching calibration strategy.

This study utilized switchable solvent liquid-phase microextraction (SS-LPME) to enrich eleven nervous system active pharmaceutical ingredients (APIs) from aqueous samples for their determination at trace levels by gas chromatography mass spectrometry. The analytes selected for the study included APIs utilized in antidepressant, antipsychotic, antiepileptic, and anti-dementia drugs. Parameters of the microextraction method including switchable solvent volume, concentration and volume of the trigger agent (sodium hydroxide), and sample agitation period were optimized univariately to boost extraction efficiency. Under the optimum conditions, the detection limits calculated for the analytes were in the range of 0.20-8.0ng/mL, and repeatability for six replicate measurements as indicated by percent relative standard deviation values were below 10%. Matrix matching calibration strategy was used to enhance quantification accuracy for the analytes. The percent recovery results calculated for the eleven analytes ranged between 86 and 117%.

Study on the Effect of Deep Eutectic Solvent Liquid Phase Microextraction on Quality Standard, Antitussive, and Expectorant of Sangbaipi Decoction.

The SD was extracted with a new green eutectic solvent, and the extraction method of TCM decoction was developed. In the quantitative analysis by HPLC, choline chloride phenol was selected as the eutectic solvent, THF was used as the extractant, and investigation of DES type, DES molar ratio, DES-to-THF ratio, vortex time, and material-to-liquid ratio was carried out. The experimental results showed that the optimal extraction method was as follows: the molar ratio of DES was 1 : 3, and the material-liquid ratio was 5 : 1200 (mL/μL). The volume ratio of DES to THF was 1200 : 800 (μL), the vortex time was 3 min, and the extraction was repeated two times. The eutectic solvent liquid phase microextraction method was adopted to optimize the extraction method of SD and reduce the complicated processing, long time, and low efficiency of traditional methods. At the same time, in the mouse ammonia water inducing cough and phenol red excretion and expectorant experiments, SD high- and medium-dose groups have a significant inhibitory effect on the frequency of antitussive in mice and both can increase the excretion of phenol red to varying degrees, indicating that SD has good cough-relieving and expectorant effect. The present study suggests a scientific basis and basis for the clinical research and quality standard formulation of SD.

A miniaturized simple binary solvent liquid phase microextraction (BS-LPME) procedure for pesticides multiresidues determination in red and rosè wines

The determination of pesticides at trace or ultratrace levels, employing low volumes of organic solvents, in complex and dark colored samples as red and/or rosè wines, still represents a challenge in chemical analysis. In this work, we developed a simple and very effective sample preparation procedure based on binary solvent liquid phase microextraction (BS-LPME) for the determination of seventeen multiresidue pesticides in red and rosè wines. The extraction device was composed of a 10 mL headspace vial containing a metal crap with a silicone septum and a capillary tube for organic phase collection. The developed procedure was validated and applied in fourteen wine samples. The method showed good linearity (R2 ≥ 0.9987). The limit of detection and limit of quantification ranged from 0.044 μg L−1 (permethrin I) to 0.233 μg L−1 (disulfoton) and from 0.294 μg L−1 (fenitrothion) to 0.777 μg L−1 (disulfoton), respectively. The intraday precision values ranged from 2.9% (ethion) to 16.8% (fenitrothion), whereas the interday precision values were below or equal to 20% for most pesticides. The proposed procedure showed accuracy in the recommended range for complex samples, between 58% (disulfoton) and 121% (molinate), except for parathion and azoxystrobin, due to possible interactions between these compounds and other substances present in the wine matrix. The proposed method showed high sensitivity, which enabled the detection and quantification of low levels of pesticide residues (<0.099 μg L−1 to 24.8 μg L−1) in real samples of red and rosè wines.

A new strategy for the combination of supramolecular liquid phase microextraction and UV–Vis spectrophotometric determination for traces of maneb in food and water samples

A novel and green method was developed for enrichment of maneb (manganese ethylene-bisdithiocarbamate) with a supramolecular solvent liquid phase microextraction method. The microextraction method has been used for the first time in the literature for separation-preconcentration of maneb. 1-decanol and tetrahydrofuran were used in the supramolecular solvent formation. The Mn2+ content of maneb was extracted in the supramolecular solvent phase as 1-(2-pyridylazo)-2-naphthol complex at pH 12.0. Manganese concentration was determined by UV–Vis spectrophotometer at 555 nm. Then, the maneb concentration equivalent to manganese concentration was calculated. The analytical parameters which effective in the method, including pH, volume of reagents, and sample volume were optimized. The limit of detection and the limit of quantification values for maneb were calculated as 2.22 μg L−1 and 7.32 μg L−1, respectively. The method was successfully applied in the analysis of the maneb content of water and food samples.

A sensitive determination method for trace bisphenol A in bottled water and wastewater samples: Binary solvent liquid phase microextraction-quadrupole isotope dilution-gas chromatography-mass spectrometry

A sensitive, accurate and precise methodology was established for the preconcentration and determination of bisphenol A in bottled water and wastewater samples at trace levels. A binary solvent liquid phase microextraction (BSLPME) method was optimized to extract bisphenol A before determination by gas chromatography-mass spectrometry (GC-MS). The type of binary solvent/disperser solvent, vortex period and mode of adding extraction and disperser solvent mixture to aqueous solution were determined by univariate optimization. Three significant parameters including volume of binary solvent, volume of dispersive solvent and ratio of binary solvent were optimized using Box-Behnken Design. Low limit of detection (0.30 ng/g) and limit of quantitation (0.99 ng/g) values were recorded for the BSLPME-GC-MS method. Hence, 173 times enhancement in the detection limit of the GC-MS system was achieved by the developed microextraction method. Quadrupole isotope dilution (ID4) strategy was used to augment the extraction method to achieve high accuracy and precision. When the developed BSLPME method was combined with the ID4 strategy, bottled water and wastewater samples spiked at approximately 200 ng/g recorded excellent recovery results of 100.3 ± 0.4% and 100.0 ± 0.5%, respectively. Therefore, accurate and precise determination of bisphenol A at trace levels was achieved by a low cost, rapid and green analytical method.

Simple and Green Vortex-Assisted Switchable Solvent Liquid Phase Microextraction for the Determination of Indium in Soil with Matrix Matching and Slotted Quartz Tube (SQT) – Flame Atomic Absorption Spectrometry (FAAS)

A novel preconcentration methodology to enhance the sensitivity of a flame atomic absorption spectrometer for indium determination was investigated in this study. The proposed methodology is based on the application of switchable solvent based liquid-phase microextraction combined with a slotted quartz tube. The isolation of indium was performed using N, N-dimethylbenzylamine as the extraction solvent after complexation with (E)-2,4-dibromo-6-(((3-hydroxyphenyl)imino)methyl)phenol. The detection power was enhanced by approximately 169-fold using the developed method with respect to the conventional flame atomic absorption spectrometry system. The quantification and detection limit values were 28.3 and 8.4 ng mL−1, respectively. The assessment of several interfering ions on the analyte was performed, and spike experiments were used to validate the method’s accuracy. Interferences were observed for a ratio of 1:10 analyte:interferent with a value of 27%. The recovery results obtained using matrix matching strategy indicated the applicability of the developed method for soil matrices.

Sensitive determination of nickel at trace levels in surface water samples by slotted quartz tube flame atomic absorption spectrometry after switchable solvent liquid-phase microextraction.

In this study, switchable solvent (SS) for liquid-phase microextraction (LPME) was used as a tool to preconcentrate nickel from aqueous samples for determination by flame atomic absorption spectrometry. The SS-LPME method was optimized thoroughly to boost the absorbance signal of nickel for trace level determination. Parameters optimized included switchable solvent volume, sodium hydroxide concentration, sodium hydroxide volume, and eluent volume. The SS-LPME method enhanced the detection power by about 32-folds, and a slotted quartz tube (SQT) was used to obtain 2.6-folds increase in detection power. The combination of LPME and SQT-FAAS produced 104-folds enhancement, correlating to a limit of detection value of 1.8μg/L. Low relative standard deviations calculated for the lowest calibration concentration indicated good repeatability for replicate measurements. Accuracy of the optimized method and its applicability to real samples was tested on two river samples. The results (85-103%) obtained from the spike recovery experiments were satisfactory.

Combination of ultrasound-assisted ethyl chloroformate derivatization and switchable solvent liquid-phase microextraction for the sensitive determination of l-methionine in human plasma by GC-MS.

A green and fast analytical method for the determination of l-methionine in human plasma is presented in this study. Preconcentration of the analyte was carried out by switchable solvent liquid phase microextraction after ethyl chloroformate derivatization reaction. Instrumental detection of the analyte was performed by means of gas chromatography-mass spectrometry. N,N-Dimethyl benzylamine was used in the synthesis of switchable solvent. Protonated N,N-dimethyl benzylamine volume, volume/concentration of sodium hydroxide, and vortex period were meticulously fixed to their optimum values. Besides, ethyl chloroformate, pyridine, and ethanol volumes were optimized in order to get high derivatization yield. After the optimization studies, limit of detection and quantitation values were attained as 3.30 and 11.0ng/g, respectively, by the developed switchable solvent liquid phase microextraction gas chromatography-mass spectrometry method that corresponding to 76.7-folds enhancement in detection power of the gas chromatography-mass spectrometry system. Applicability and accuracy of the switchable solvent liquid phase microextraction-gas chromatography-mass spectrometry method were also checked by spiking experiments. Percent recovery results were ranged from 97.8 to 100.5% showing that human plasma samples could be analyzed for its l-methionine level by the proposed method.

Determination of fenazaquin in water and tomato matrices by GC-MS after a combined QuEChERS and switchable solvent liquid phase microextraction

This study presents the use of Quick Easy Cheap Efficient Rugged and Safe (QuEChERS) as an effective sample cleaning procedure and switchable solvent liquid phase microextraction (SS-LPME) as a preconcentration tool for the determination of fenazaquin by gas chromatography mass spectrometry (GC-MS) at ultratrace levels. After a thorough optimization process, 0.50mL of switchable solvent, 1.5mL of 1.0M sodium hydroxide, and 15s of vortexing were determined as optimum conditions of the SS-LPME method. The limit of detection (LOD) and limit of quantitation (LOQ) determined using the optimum method (SS-LPME/GC-MS) were 0.05 and 0.18ng/mL, respectively. Compared with direct GC-MS determination of fenazaquin, the optimum method yielded about 800-fold enhancement in detection power of GC-MS. The method was applied to lake, irrigation canal, well, and wastewater samples. In order to test the method's applicability on fresh tomato samples, a QuEChERS method was used before applying the SS-LPME method. Matrix-matched calibration standards were used to enhance the accuracy of fenazaquin quantification in spiked tomato samples to obtain recovery results close to 100%.

A novel switchable solvent liquid-phase microextraction technique based on the solidification of floating organic droplets: HPLC-FLD analysis of polycyclic aromatic hydrocarbon monohydroxy metabolites in urine samples

A novel switchable solvent liquid-phase microextraction technique, based on the solidification of floating organic droplets (SS-LPME-SFO), was developed for the pretreatment of aqueous samples.

A green, accurate and sensitive analytical method based on vortex assisted deep eutectic solvent-liquid phase microextraction for the determination of cobalt by slotted quartz tube flame atomic absorption spectrometry

Preconcentration of cobalt was carried out with deep eutectic solvent based liquid phase microextraction (DES-LPME) for trace determination by a slotted quartz tube (SQT) attached flame atomic absorption spectrometry (FAAS) system. Choline chloride and phenol in a 1:2 M ratio was used as a green solvent to extract cobalt from the aqueous sample solution. Key parameters influencing the extraction efficiency of cobalt were examined and optimized. Under the conditions optimized, the linear dynamic range was found between 5.0 and 50 µg L−1, and the limits of detection and quantification (LOD and LOQ) were calculated as 2.0 and 6.6 µg L−1, respectively. The detection power of the conventional FAAS was improved upon by 67 folds using the optimized DES-LPME-SQT-FAAS method. The developed analytical method was successfully applied for the determination of cobalt in linden tea samples and the recovery results obtained for different spiked concentrations (20, 30 and 40 µg L−1) were remarkable (≈100%).

Validation of ultrasonic-assisted switchable solvent liquid phase microextraction for trace determination of hormones and organochlorine pesticides by GC–MS and combination with QuEChERS

QuEChERS and switchable solvent liquid phase microextraction (SS-LPME) were respectively used as pretreatment and preconcentration tools to allow trace determination of selected organochlorine pesticides and hormones by gas chromatography mass spectrometry (GC–MS). The effects of principal SS-LPME variables and their interactions were evaluated with a Box-Behnken experimental design. The limits of detection obtained by direct GC–MS determination were enhanced by about 33–115 folds under the optimized SS-LPME conditions. The SS-LPME method was applied to tap water, well water, lake water, medical wastewater and tea samples. Satisfactory recovery results were obtained for all but the tea samples using the conventional calibration plot. Matrix matched calibration standards were used to improve the percent recovery of analytes to almost 100% in the tea samples. The combined QuEChERS and SS-LPME method was applied to tomato samples and matrix matching was also used to significantly improve analyte recoveries.

An environment-friendly supramolecular solvent-based liquid–phase microextraction method for determination of aluminum in water and acid digested food samples prior to spectrophotometry

Aluminum (III) has high toxic impacts in some human pathologies like renal osteodystrophy, Parkinson's and Alzheimer's disease. So, it is very important to assess and determine the trace concentrations of Aluminum (III) in various water and acid digested food samples. The present work proposed a new green supramolecular solvent liquid–phase microextraction procedure has been sophisticated to preconcentrate and determine Aluminum (III) in various samples. The proposed method was based on the application of Undecanol/THF supramolecular solvent system and thymol blue as a chelating agent. Aluminum (III)-thymol blue complex was formed at pH 6.0, extracted into (Undecanol/THF) supramolecular solvent phase, centrifuged and spectrophotometrically measured at 550 nm. The influence of different analytical parameters was studied and optimized. The validation of the suggested preconcentration method was checked using certified reference materials. The calibration curve was linear in the range of 5.0–200 μg L−1. The developed method has preconcentration factor of 50 and detection limit was 1.20 μg L−1. The method precision was confirmed with relative standard deviation ≤1.80%. The accuracy of the new preconcentration procedure was checked by the analysis of the certified reference materials (SRM 1643e trace element in water and NIST SRM 1515 Apple Leaves), and successfully applied to determine Aluminum (III) in real samples with relative recovery values in the range of 95.0%–100% for the spiked samples. This study explores the effectiveness of thymol blue for the first time together with supramolecular solvent to develop green supramolecular solvent liquid–phase microextraction method to preconcentrate and separate of trace amount of Aluminum (III) in real samples.