Corona Discharge Ion Mobility Research Articles

Semi-automated filter micro-solid phase extraction based on urea-formaldehyde microsphere followed by corona discharge-ion mobility spectrometry for simultaneous detection of fentanyl and nor-fentanyl in urine

In this work, semi-automated filter micro-solid phase extraction (SA-FμSPE) packed by urea–formaldehyde (UF) microspheres coupled with corona discharge ionization-ion mobility spectrometry (CD-IMS) was developed for the extraction and determination of fentanyl and nor-fentanyl in urine samples. UF microspheres, synthesized by aqueous polymerization, can be used to achieve effective extraction of analytes through multiple adsorption interactions such as hydrophobic, dipole–dipole and hydrogen bonding interactions. UF microspheres dispersed in methanol were packed in the filter by syringe, and the extraction process was performed by a portable automatic filter extraction device. The parameters affecting extraction efficiency (i.e., extraction time, the flow rate of extraction, pH value, amount of sorbent, ionic strength, cycle times of desorption, and type of eluent) were investigated. Then, the eluate containing fentanyl and nor-fentanyl was simultaneously analyzed by CD-IMS in positive mode. Under the optimal extraction conditions, the detection limits for the target compounds were 5.00 ng mL−1 and 8.00 ng mL−1, respectively. The spiked recoveries were in the range of 81.97 % −112.37 % by testing the real samples and validated by UHPLC-MS. Thus, the satisfactory results reveal that SA-FμSPE coupled with CD-IMS has great potential for on-site extraction and detection of fentanyl and nor-fentanyl in urine samples.

Fe3O4@nitrogen-doped carbon core-double shell nanotubes as a novel and efficient nanosorbent for ultrasonic assisted dispersive magnetic solid phase extraction of heterocyclic pesticides from environmental soil and water samples.

Fe3O4@nitrogen-doped carbon core-double shell nanotubes (Fe3O4@N-C C-DSNTs) were successfully synthesized and applied as a novel nanosorbent in ultrasonic assisted dispersive magnetic solid phase extraction (UA-DMSPE) of tribenuron-methyl, fenpyroximate, and iprodione. Subsequently, corona discharge ion mobility spectrometry (CD-IMS) was employed for the detection of the extracted analytes. Effective parameters on theextraction recovery percentage (ER%) were systematically investigated and optimized. Under optimal conditions, UA-DMSPE-CD-IMS demonstrated remarkable linearity in different ranges within 1.0 - 700 ng mL-1 with correlation coefficients exceeding 0.993, repeatability values below 6.9%, limits of detection ranging from 0.30 to 0.90 ng mL-1, high preconcentration factors (418 - 435), and ER%values (83 - 87%). The potential of the proposed method was further demonstrated by effectively determining the targeted pesticides in various environmental soil and water samples, exhibiting relative recoveries in the range 92.1 - 102%.

Protonation of gabapentin: Ion mobility spectrometry and computational study.

Protonation of gabapentin was studied using corona discharge ion mobility spectrometry with two types of reactant ions at temperature of 200°C. It was found that at elevated temperatures, ionization of gabapentin proceeds via two channels, including the protonation and reactant ion attachment, in the presence of both hydronium and ammonium reactant ions. The effect of the sample concentration on the relative intensity of product ion peaks was also studied. It turned out that in high concentrations, in addition to the protonation of gabapentin, binding of the reactant ion and the formation of proton-bound dimer also occurred, while in low concentrations, the only product of the ionization process is protonated gabapentin. Density functional theory (DFT) with B3LYP and M062X functionals employing the same basis set 6-311++G(d,p) was used to extend the experimental findings. The structures of the several conformers of neutral and protonated gabapentin were obtained. Based on them, topical proton affinity and topical gas-phase basicity of gabapentin were calculated for selected conformers. The attachment of reactant ions to neutral gabapentin and formation of proton-bound dimer were thermodynamically studied.

Amylodextrin hydrogel as a green sorbent for pipette-tip micro-solid phase extraction followed by ion mobility spectrometry for analysis of triazole fungicides in environmental water samples

Triazole compounds have been globally used for controlling fungal diseases such as rusts, powdery mildew, and many leaf-spotting fungi. These compounds also have adverse effects on the environment and human health. In the present work, a hydrogel-based sorbent was synthesized by a combination of hydrophilic acrylic polymer and biodegradable amylodextrin. The sorbent was characterized by Fourier-transform infrared (FT-IR) spectroscopy, Brunauer-Emmett-Teller (BET) surface area, elemental CHN analysis, field emission scanning electron microscopy (FE-SEM), and zeta potential. The synthesized hydrogel was used as a green sorbent in the pipette-tip micro-solid phase extraction procedure for extraction and quantification of triazole fungicides (penconazole, hexaconazole, and tebuconazole) in environmental water samples. The corona discharge-ion mobility spectrometry (CD-IMS) was used as a rapid and sensitive detection technique. The effects of important variables on the extraction efficiency were optimized by response surface methodology (RSM). The proposed method provided good linearity (r2 ≥ 0.995) over a concentration range of 0.5–1000 ng/mL, acceptable intra-day RSD (≤ 5.7%, n = 5) and inter-day RSD (≤ 8.7%, n = 5), low limits of detection (0.10–0.20 ng/mL), good preconcentration factors (16.9–17.9 times), and high extraction recoveries (93.1–98.3%) under optimum extraction conditions. The extraction conditions were as follows: the amount of sorbent: 6.0 mg, pH of sample solution: 7.5, the flow rate of sample solution: 2.0 mL/min, adsorption time: 16.5 min, volume of desorption solvent: 1.1 mL, the flow rate of desorption solvent: 0.5 mL/min, and desorption time: 11.7 min. Finally, the proposed method was successfully applied for the quantification of triazoles in river and agricultural water samples.

Analysis of methamphetamine, methadone, tramadol, and buprenorphine in biological samples by ion mobility spectrometry after electromembrane extraction in tandem with slug flow microextraction

A novel tandem extraction method based on electromembrane extraction (EME) and slug flow microextraction (SFME) was developed for the extraction of some narcotics (methamphetamine, methadone, tramadol, and buprenorphine) from biological samples. The analytes were quantified by corona discharge-ion mobility spectrometry (CD-IMS). In this method, initially, analytes were extracted using an EME procedure (step-1). After that, the acceptor solution of the first step containing target analytes was applied in an SFME procedure (step-2) as a donor solution for further preconcentration. In the second step, analytes were extracted from an aqueous solution into an organic extractant. The optimum EME and SFME conditions were as follows: type of supported liquid membrane: 2-nitrophenyl octyl ether containing 10% v/v di-(2-ethylhexyl) phosphate, acceptor solution pH: 1.0, sample solution pH: 4.0, voltage: 248 V, extraction time: 17.5 min, tilting number of glass capillary tube: 10 times, type of the organic extractant: toluene, the concentration of NaOH solution: 400 mM. Under optimum extraction conditions, good linearity was obtained in the range of 0.50-750.0 ng/mL with coefficients of determination (r2) ≥ 0.991. The limits of detection and quantification were achieved in the range of 0.15-3.5 ng/mL and 0.50-12.0 ng/mL, respectively. The inter-day and intra-day precisions (n = 3) provided RSDs lower than 12.8% and 12.7%, respectively. Enrichment factors and extraction recoveries of the analytes were in the range of 255.7 to 505.4 and 37.6-78.3%, respectively. Comparing the EME/HPLC-UV with EME-SFME/CD-IMS showed that using the tandem extraction method improved the enrichment factors by more than 2.7 times and limits of detection and quantification by more than 15 times. Finally, this procedure was used to quantify target analytes in plasma and urine samples.

Exploring and modeling the ion mobility spectrometry of perindopril: Example of protonation-dissociation reactions in large molecules.

The current research is constructed for considering the chemical ionization and dissociation of perindopril in the positive mode of corona discharge ion mobility spectrometry. Four product ion peaks are observed in the ion mobility spectrum of perindopril erbumine at the cell temperature of 473 K. These peaks are assigned through the obtained intensity variation analysis in the ion mobility spectra over the elapsed time accompanied by the calculations backed by the validated density functional theory (DFT). In this regard, the most stable ionic species associated with each peak and the corresponding reliable generation pathways are found by the well-confirmed meta hybrid density functional method, M06-2X. The peaks are assigned to the protonated perindopril and its dissociation products, including counter ion and the related fragment ions. However, the structures of the neutral perindopril in the gas phase are thoroughly assessed to find a more stable one. The predicted chemical ionization products by the theory are in excellent agreement with our presented experiment here. Theoretical evaluations demonstrated that the production of a fragment by dissociation process occurs when perindopril gets a proton from the ionization region. Also, without protons, there is no dissociation process. Therefore, our mechanism investigated here is the proton transfer one. All possible sites of perindopril are considered theoretically for protonation along with their possible reactions. In addition to the computed PES, the assigned ions for obtained spectra are confirmed by the computed equilibrium constants and rate constants. Our theoretical results show that the peak of the main fragment is for M-CH3 CH2 OH produced by a reaction pathway involving no barrier. This study opens new perspectives in interpreting large molecules spectra for future studies.

Silica aerogel modified electrospun polyacrylonitrile as a sorbent for thin-film microextraction of chlorpyrifos from real samples coupled with corona discharge ion mobility spectrometry detection.

In this paper, modified polyacrylonitrile/silica aerogel fibers were prepared and used as an adsorbent for thin-film microextraction of chlorpyrifos. The extracted analyte was analyzed by corona discharge ion mobility spectrometry. The electrospinning method was applied for the preparation of polyacrylonitrile fibers. The alkaline hydrolyzation technique was used to modify the electrospun film surface. Silica aerogel was synthesized on the surface of modified electrospun polyacrylonitrile fibers by the in situ growth technique. To access a high extraction yield, effective synthesis and extraction parameters such as NaOH concentration, reaction temperature and time, thin-film pretreatment, gelation time, solution pH, ionic strength, and extraction time were studied. The linearity range and the limit of detection of the method were 1-100 μg L-1 and 0.3 μg L-1, respectively. The precision of the method was 4 and 12% for the concentration levels of 5 and 60 μg L-1, respectively. Chlorpyrifos was successfully determined by the method in well water, river water, agricultural wastewater, and tangerine samples.

Rapid screening of chemical warfare agents (nerve agents) using dimethyl methylphosphonate as simulant substances in beverages by hollow fiber membrane-protected solid phase microextraction followed by corona discharge ion mobility spectrometry

The following work presents a new, rapid, potential to be portable, convenient, and low-cost method using hollow fiber membrane-protected solid phase microextraction followed by corona discharge ion mobility spectrometry which was used for determining dimethyl methylphosphonate in beverages. Response surface methodology based on the design of Box-Behnken was implemented for optimizing the different factors influencing the proposed method for obtaining the best results. Optimal extractions were calculated with 65 µm polydimethylsiloxane-divinylbenzene fiber, fiber equilibration time of 10 min, stirring rate of the sample solution at 750 rpm, and extraction temperature of 50 °C. The proposed technique provided linear range (0.5–50 µg mL−1), good linearity (>0.991), and repeatability (the relative standard deviations of 5.42% and 8.37% of intra- and inter-day analyses, respectively) under the optimized extraction conditions. Finally, the developed method was successfully used for determining dimethyl methylphosphonate in beverages such as coffee mix, fruit juice, tap water, milk, and tea.

High efficient solid-phase microextraction based on a covalent organic framework for determination of trifluralin and chlorpyrifos in water and food samples by GC-CD-IMS

Novel porous covalent organic framework (COF) based on condensation reaction between cyanuric chloride, 4,4′-ethylendianiline, and 3,4,9,10-perylenetetracarboxylic dianhydride was synthesized via sealed tube condition. The results COF was used as a new adsorbent for solid-phase microextraction (SPME) for extracting trifluralin and chlorpyrifos from vegetables, fruit samples, and wastewater. Gas chromatograph with a corona discharge-ion mobility spectrometer as the detector was also used for analyzing the target analytes. Some parameters that affected the extraction, such as stirring rate, time and temperature of extraction and pH were investigated, exhaustively. The detection limits were 0.13, and 0.15 µg/L and the linear ranges of 0.45–20 and 0.50–25 µg/L with a linearity coefficient of 0.9965 and 0.9987 were also obtained for trifluralin and chlorpyrifos, respectively. The method was applied successfully to analyze some real samples of cucumber, carrot, grape, and agriculture wastewater, and the results showed a relative recovery in the range of 87% to 110%.

Synthesis of magnetic Cu/CuFe2O4@MIL-88A(Fe) nanocomposite and application to dispersive solid-phase extraction of chlorpyrifos and phosalone in water and food samples

Herein, a novel Cu/CuFe2O4@iron-based metal-organic framework 88 A (Cu/CuFe2O4@MIL-88A(Fe)) was developed through a scalable hydrothermal strategy for the magnetic dispersive solid-phase extraction of chlorpyrifos and phosalone from water, fruit juice, and vegetable samples prior to corona discharge ion mobility spectrometry analysis. The resulting nanocomposite was characterized in detail, and thus the investigation indicated that the magnetic nanocomposite had good adsorption capacity, high surface area, dispersion, and superparamagnetic properties. In addition, the fabricated sorbent provided different interactions with the target analytes, (hydrogen bonding, hydrophobic contacts, and π-π stacking interactions) resulting in the improvement of extraction efficiency. The applied method based on Cu/CuFe2O4@ MIL-88A(Fe) was validated by investigating the affecting parameters, including the amount of magnetic nanocomposite (10.0 mg), sample pH (7.0), salt content (7.5 % w/v), extraction time (5 min), type of elution (150 μL of methanol), and desorption time (2 min). The linearity of the method was found to be in the range of 0.6–300.0 ng mL−1 and 1.5–500.0 ng mL−1, for chlorpyrifos and phosalone with the coefficient of determination of ≥0.9991. The limits of detections (LODs) of 0.2 and 0.5 ng mL− 1 were obtained for the determination of chlorpyrifos and phosalone, respectively. The relative standard deviation values (RSDs %) were calculated in the range of 4.4 %–6.1 % (intra-day, n = 5) and 6.3 %–8.0 % (inter-day, n = 3) for three days. Ultimately, the developed method was successfully applied for the extraction of the desired analytes from various spiked samples with acceptable recoveries (88.3–100.4 %).

In situ growth of copper-based metal-organic framework on a helical shape copper wire as a sorbent in stir-bar sorptive extraction of fenthion followed by corona discharge ion mobility spectrometry

In this paper, a helical copper wire, coated with copper-benzene-1,4-dicarboxylic acid metal-organic framework (Cu-BDC) was used as a sorbent for stir-bar sorptive extraction of fenthion from water and fruit samples. The homogenous coating was fabricated through two simple and fast steps. The chemical conversion of copper substrate to copper hydroxide nanotubes (Cu(OH)2 NTs) was performed in an alkaline solution and then Cu-BDC was formed through a neutralization reaction. Corona discharge ion mobility spectrometry in positive mode was applied for the detection of fenthion. To improve the sensitivity of the method, some synthesis and extraction parameters affecting the extraction efficiency such as benzene-1,4-dicarboxylic acid concentration, ionic strength, sample pH, stirring rate, extraction temperature, and extraction time were investigated. The linear dynamic range between 0.5 and 80 μg L−1 and detection limit of 0.1 μg L−1 were obtained under optimal conditions. The intra- and inter-day relative standard deviations were less than 6.4 and 8.6%, respectively. The applicability of the method was examined for the analysis of different samples (i.e., well water, agricultural wastewater, and orange). The recovery for the determination of fenthion in spiked samples varied from 88 to 111%.

Preparation of Polyacrylonitrile/Ni-MOF electrospun nanofiber as an efficient fiber coating material for headspace solid-phase microextraction of diazinon and chlorpyrifos followed by CD-IMS analysis

Herein, an electrospun polyacrylonitrile/nickel-based metal–organic framework nanocomposite (PAN/Ni-MOF) coating on a stainless steel wire was synthesized and employed as a novel nanosorbent for headspace solid-phase microextraction (HS-SPME) of organophosphorus pesticides (OPPs), diazinon (DIZ), and chlorpyrifos (CPS) from the diverse aqueous media followed by corona discharge ion mobility spectrometry (CD-IMS). Under the optimum experimental conditions, the calibration plots were linear in the range of 1.0–250.0 ng mL−1 for DIZ and 0.5–300.0 ng mL−1 for CPS with r2 > 0.999. The detection limits (S/N = 3) were 0.3 and 0.2 ng mL−1 for DIZ and CPS, respectively. The intra-day relative standard deviations (RSDs%) (n = 5) at the concentration levels of 20.0, 40.0, and 100.0 ng mL−1 were ≤ 5.2%. To investigate the extraction efficiency, PAN/Ni-MOF was employed to analyze various juice samples, including orange, apple, and grape juices, and in three water samples where it led to good recoveries ranged between 87% and 98%.

Gelatin microsphere coated Fe3O4@graphene quantum dots nanoparticles as a novel magnetic sorbent for ultrasound-assisted dispersive magnetic solid-phase extraction of tricyclic antidepressants in biological samples.

Gelatin microsphere-coated Fe3O4@graphene quantum dots (Fe3O4@GQD@GM) were designed and synthesized as a novel sorbent via ultrasonic-assisted dispersive magnetic solid-phase extraction (UA-DMSPE) method. The synthesized sorbent was identified and confirmed by FT-IR, XRD, VSM, and SEM techniques. UA-DMSPE was combined with corona discharge ion mobility spectrometry for trace determination of desipramine, sertraline, and citalopram. Effective parameters were considered and optimized. The proposed method, under optimal conditions, showed excellent linearity in different concentration ranges (2-700ng mL-1, R2 > 0.995), repeatability (RSD < 5.1%), good sensitivity (LODs in the range 0.6-1.5ngmL-1), high preconcentration factor (PF = 207-218), and acceptable relative recoveries (93.5-101.8%). Eventually, this method was used to determine tricyclic antidepressants in various biological samples. Schematic presentation of the microextraction and monitoring of TCAs by ultrasonic-assisted dispersive magnetic solid phase microextraction-ion mobility spectrometry producer.

Investigation of corona discharge ionization of barbituric acid using ion mobility spectrometry along with quantum chemical calculations.

This study aimed at examining atmospheric-pressure chemical ionization of barbituric acid through the corona discharge ion mobility spectrometry (CD-IMS) and the quantum chemical calculations. The results indicated two product ion peaks in the IMS spectrum of barbituric acid. The thermal decomposition of the barbituric acid sample was investigated by scanning the temperature of the injection port and analyzing the temporal evolution of the IMS peaks over elapsed time. It was found that the barbituric acid sample was not thermally decomposed in the injection port of the instrument. Experimental evidences were collected by changing the reactant ions, concentration of barbituric acid sample, and IMS cell temperature. The two observed peaks were then assigned to cationic form and oxygen protonated isomers of barbituric acid. The positions of the product ion peaks were explicated considering the dipole moments of the product ions.

Fabrication of Co3O4 quantum dot incorporated polyacrylamide ethylene glycol dimethacrylate as a new fiber for solid phase microextraction and trace determination of organophosphorus pesticides in environmental water samples.

In this paper, a novel solid phase microextraction fiber based on Co3O4 quantum dot incorporated polyacrylamide-co-ethylene glycol dimethacrylate followed by corona discharge ion mobility spectrometry is presented for the trace determination of organophosphorus pesticides in environmental water samples. Ion mobility spectrometry is a comparatively inexpensive, well-known, robust, and easy to operate analytical instrument. This combination would provide a low-cost, fast, selective, and sensitive quantitative system for detection of organophosphorus pesticides. In order to obtain the best extraction efficiency, the optimization of parameters affecting this method was carried out. After optimization, a solution pH of 7.0, extraction temperature of 60 °C, adsorption temperature of 260 °C, extraction time of 30 min, stirring speed of 750 rpm, and ionic strength of 10% w/w were obtained. Consequently, the presented method showed low limits of detection (0.3-0.6 ng mL-1), excellent enrichment factors (PF = 221-263), good linearity (R2 > 0.995), and repeatabilities (intra-day: 3.4 to 4.8%) and (inter-day: 4.7 to 6.1%). The reproducibility (RSD% of fiber to fiber) was also investigated by analyzing three as-prepared fibers under the same conditions and was found to be less than 7.6%. Finally, the developed fiber was used for determination of organophosphorus pesticides in the field samples.

Covalent triazine-based framework-grafted functionalized fibrous silica sphere as a solid-phase microextraction coating for simultaneous determination of fenthion and chlorpyrifos by ion mobility spectrometry.

A novel covalent triazine-based framework (CTF)-grafted phenyl-functionalized fibrous silica nanosphere, KCC-1 (named as RS-2) was synthesized via a simple and effective Friedel-Crafts approach. The microporous CTF with fluorene backbone was coupled and grown uniformly on the surface of phenyl-functionalized KCC-1 to prepare a hybrid extended porous framework. The prepared materialswere characterized, and FE-SEM and TEM images revealed a flower-like structure for RS-2. The synthesized RS-2 showed excellent thermal stability, so the weight loss was about 30% at 800°C. RS-2 was applied as a new coating in the solid-phase microextraction procedure to extract chlorpyrifos and fenthion pesticides fromwater, wastewater, and fruit samples, before determining by corona discharge-ion mobility spectrometry. Some experimental factors affecting the extraction yield of the analytes, including ionic strength, stirring rate, sample pH, extraction temperature, and extraction time, were investigated. Under optimum conditions, the linear dynamic ranges were 0.1-10μgL-1 and 1.0-70μgL-1, and the limits of detection were 0.05 and 0.55μgL-1 for chlorpyrifos and fenthion, respectively. The proposed method showed recovery values in the range 86-117% with a precision of 3.0-7.1% for real samples. Covalent triazine-based framework (CTF)-grafted phenyl-functionalized fibrous silica nanosphere (named as RS-2) was synthesized. RS-2 was applied as a sorbent for solid-phase microextraction (SPME) of chlorpyrifos and fenthion from fruit and water samples followed by corona discharge ionization ion mobility spectrometry (CD-IMS).

Corona discharge ion mobility spectrometry combined by homogenizer assisted dispersive liquid-phase microextraction; A rapid and sensitive method for quantification of nortriptyline

In this research, homogenizer assisted dispersive liquid-phase microextraction has been used as an efficient and fast extraction-preconcentration procedure of nortriptyline from different samples. The ultimate analysis of nortriptyline was done by the ion mobility spectrometry technique. A laboratory homogenizer has been employed as the dispersing element for the emulsification of extracting organic solvent. The effective parameters on the extraction process including type and volume of extraction solvent, sample ionic strength and sample solution pH, homogenization time, and dispersing rate were investigated and optimized. The evaluated optimal values of these parameters were found to be 40 µL of dibromomethane as the extraction solvent, sample solutions pH of 10, 10 w/v% of NaCl for adjusting the ionic strength, dispersing rate of 16000 rpm and the homogenizing time of 6 s. The calibration curve was linear in the range of 5 to 200 μg L−1 with the detection limit of 1.9 μg L−1, and the calculated intra- and inter-day precisions based on the corresponding relative standard deviations were found to be 4.0% and 4.6%, respectively. The proposed method was evaluated for the determination of nortriptyline in human breast milk, urine, and a river water samples. The relative recoveries for studied samples were between 91.2 and 105.7%.

Mechanism of atmospheric pressure chemical ionization of morphine, codeine, and thebaine in corona discharge-ion mobility spectrometry: Protonation, ammonium attachment, and carbocation formation.

Atmospheric pressure chemical ionizations (APCIs) of morphine, codeine, and thebaine were studied in a corona discharge ion source using ion mobility spectrometry (IMS) at temperature range of 100°C-200°C. Density functional theory (DFT) at the B3LYP/6-311++G(d,p) and M062X/6-311++G(d,p) levels of theory were used to interpret the experimental data. It was found that in the presence of H3 O+ as reactant ion (RI), ionization of morphine and codeine proceeds via both the protonation and carbocation formation, whereas thebaine participates only in protonation. Carbocation formation (fragmentation) was diminished with decrease in the temperature. At lower temperatures, proton-bound dimers of the compounds were also formed. Ammonia was used as a dopant to produce NH4 + as an alternative RI. In the presence of NH4 + , proton transfer from ammonium ion to morphine, codeine, and thebaine was the dominant mechanism of ionization. However, small amount of ammonium attachment was also observed. The theoretical calculations showed that nitrogen atom of the molecules is the most favorable proton acceptor site while the oxygen atoms participate in ammonium attachment. Furthermore, formation of the carbocations is because of the water elimination from the protonated forms of morphine and codeine.

Application of MIL-53(Al) prepared from waste materials for solid-phase microextraction of propranolol followed by corona discharge-ion mobility spectrometry (CD-IMS)

In this study, MIL-53(Al) metal-organic framework was prepared from waste raw materials. A polyethylene terephthalate (PET) plastic bottle was used as the source of terephthalic acid, and an aluminium beverage can was applied as the precursor of aluminium salt. The activated MIL-53(Al) was immobilized onto a stainless steel probe of the ion mobility spectrometer (IMS), and the coated probe was used for solid-phase microextraction of propranolol from biological samples before determination. The effect of the different parameters such as pH, ionic strength, and stirring rate of the sample, extraction time, and temperature was studied on the extraction efficiency of propranolol. The linearity was obtained ranging from 5−200 μg L−1 with a determination coefficient (R2) of 0.9988, and the detection limit was calculated 1.7 μg L−1 in the water sample. The relative standard deviations of the method were in the range of 2.5–12.2 %. Finally, the method was utilized for determination of propranolol in the tablet sample.

Development of a new electromembrane extraction combined with ion mobility spectrometry for the quantification of malachite green in water samples

In this study, a new method based on electromembrane extraction (EME) followed by corona discharge ion mobility spectrometry (CD-IMS) was used for preconcentration and quantification of malachite green in water samples. In the EME procedure, the charged malachite green migrated into the supported liquid membrane (SLM) under an applied potential. The extraction efficiency of malachite green was assessed based on two phase EME under effective parameters including applied voltage, extraction time, pH of the sample solution, stirring rate, and salt addition in the sample solution. The analytical performance of the developed EME method was studied under the optimum extraction condition. The dynamic linear range and low limit of detection of the EME method were 5???250 ng mL???1 and 1.5 ng mL???1, respectively. The preconcentration factor of 150 and the RSD% of 3.8???7.6% were also achieved using EME method. Finally, the proposed method was successfully tested for the extraction and analysis of malachite green in different water samples.