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1.
Anal Chem ; 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38917332

ABSTRACT

A versatile millifluidic 3D-printed inverted Y-shaped unit (3D-YSU) was prototyped to ameliorate the concentration capability of nonsupported microelectromembrane extraction (µ-EME), exploiting optosensing detection for real-time monitoring of the enriched acceptor phase (AP). Continuous forward-flow and stop-and-go flow modes of the donor phase (DP) were implemented via an automatic programmable-flow system to disrupt the electrical double layer generated at the DP/organic phase (OP) interface while replenishing the potentially depleted layers of analyte in DP. To further improve the enrichment factor (EF), the organic holding section of the OP/AP channel was bifurcated to increase the interfacial contact area between the DP and the OP. Exploiting the synergistic assets of (i) the continuous forward-flow of DP (1050 µL), (ii) the unique 3D-printed cone-shaped pentagon cross-sectional geometry of the OP/AP channel, (iii) the bifurcation of the OP that creates an inverted Y-shape configuration, and (iv) the in situ optosensing of the AP, a ca. 24 EF was obtained for a 20 min extraction using methylene blue (MB) as a model analyte. The 3D-YSU was leveraged for the unsupervised µ-EME and the determination of MB in textile dye and urban wastewater samples, with relative recoveries ≥88%. This is the first work toward analyte preconcentration in µ-EME with in situ optosensing of the resulting extracts using 3D-printed millifluidic platforms.

2.
Anal Chim Acta ; 1297: 342362, 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38438239

ABSTRACT

BACKGROUND: There is a quest of novel functional and reliable platforms for enhancing the efficiency of microextraction approaches in troublesome matrices, such as industrial wastewaters. 3D printing has been proven superb in the analytical field to act as the springboard of microscale extraction approaches. RESULTS: In this work, low-force stereolithography (SL) was exploited for 3D printing and prototyping bespoke fluidic devices for accommodating nonsupported microelectromembrane extraction (µEME). The analytical performance of 3D-printed µEME devices with distinct cross-sections, including square, circle, and obround, and various channel dimensions was explored against that of commonly used circular polytetrafluoroethylene (PTFE) tubing in flow injection systems. A computer-controlled millifluidic system was harnessed for the (i) automatic liquid-handling of minute volumes of donor, acceptor, and organic phases at the low µL level that spanned from 3 to 44 µL in this work, (ii) formation of three-phase µEME, (iii) in-line extraction, (iv) flow-through optical detection of the acceptor phase, and (v) solvent removal and regeneration of the µEME device and fluidic lines. Using methylene blue (MB) as a model analyte, experimental results evinced that the 3D-printed channels with an obround cross-section (2.5 mm × 2.5 mm) were the most efficient in terms of absolute extraction recovery (59%), as compared to PTFE tubing of 2.5 mm inner diameter (27%). This is attributed to the distinctive convex interface of the organic phase (1-octanol), with a more pronounced laminar pattern, in 3D-printed SL methacrylate-based fluidic channels against that of PTFE tubing on account of the enhanced 1-octanol wettability and lower contact angles for the 3D-printed devices. The devices with obround channels were leveraged for the automatic µEME and in-line clean-up of MB in high matrix textile dyeing wastewater samples with relative recoveries ≥81%, RSD% ≤ 17.1% and LOD of 1.3 mg L-1. The 3D-printed nonsupported µEME device was proven superb for the analysis of wastewater samples with an elevated ionic strength (0.7 mol L-1 NaCl, 5000 mg L-1 Na2CO3, and 0.013 mol L-1 NaOH) with recorded electric currents below 12 µA. NOVELTY: The coupling of 3D printing with nonsupported µEME in automatic flow-based systems is herein proposed for the first time and demonstrated for the clean-up of troublesome samples, such as wastewaters.

3.
J Chromatogr A ; 1719: 464753, 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38394784

ABSTRACT

In this study, MIL-88(Fe) coordinated to carboxymethyl cellulose fibers was successfully synthesized, characterized, and utilized as a nanocomposite for the dispersive solid phase microextraction of butachlor and acetochlor. These analytes served as representative analytes for acetanilide herbicides (AHs) present in real samples. Effective parameters on the extraction efficiency were investigated to maximize the analytical performance of the developed method. Under optimized conditions, which encompassed sorbent amount of 12 mg, solution pH of 7.0, 4.0 min of the vortex time, 3.0 min of the extraction time, chloroform as desorption agent and no salt addition, the developed method exhibited remarkable figures of merit, such as high linearity (R2> 0.99), low limits of detection of 0.90 ng mL-1, substantial preconcentration factors (between 213 and 228), relative recoveries in the range of 90.8% to 109%, and good repeatability with relative standard deviations equal or below 7.2%. After validation, the developed method was applied to detect AHs in various cereal and agricultural soil samples.


Subject(s)
Herbicides , Liquid Phase Microextraction , Nanocomposites , Solid Phase Microextraction/methods , Herbicides/analysis , Carboxymethylcellulose Sodium , Edible Grain/chemistry , Soil , Acetanilides/chemistry , Solid Phase Extraction/methods , Liquid Phase Microextraction/methods
4.
Mikrochim Acta ; 191(2): 98, 2024 Jan 16.
Article in English | MEDLINE | ID: mdl-38227067

ABSTRACT

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 the extraction 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%.

6.
Food Chem ; 403: 134273, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36174345

ABSTRACT

Herein, an ultrasound-assisted dispersive solid phase microextraction (UA-DSPME) approach has been described for trace level analysis of triazole fungicides in real samples. For this purpose, a new nanosorbent was prepared through modification of carboxymethylcellulose biopolymer with zinc-based metal-organic framework and graphene oxide, and fully characterized. Then, the effect of extraction parameters on extraction efficiency was optimized for the microextraction process. Finally, desorbed triazole fungicides with ethanol were determined using gas chromatography equipped with flame ionization detector. This technique provided good linearity (R2 > 0.99), low detection limits (0.3-1.5 ng mL-1), high preconcentration factors (419-426), good relative recoveries (91.6-102 %), and high repeatability (RSD < 4.1 %) at optimized conditions (amount of sorbent: 15 mg; pH of solution: 7.0; and extraction time; 4 min). Ultimately, this approach was applied to determine triazole fungicides in different water and food samples.


Subject(s)
Fungicides, Industrial , Liquid Phase Microextraction , Nanocomposites , Solid Phase Microextraction/methods , Fungicides, Industrial/analysis , Vegetables/chemistry , Triazoles/analysis , Fruit/chemistry , Water/analysis , Cellulose/analysis , Ultrasonics , Nanocomposites/analysis , Liquid Phase Microextraction/methods , Solid Phase Extraction , Limit of Detection
7.
ACS Sens ; 7(10): 3161-3168, 2022 10 28.
Article in English | MEDLINE | ID: mdl-36200176

ABSTRACT

A fully automatic millifluidic sensing platform coupling in-line nonsupported microelectromembrane extraction (µ-EME) with electrochemical detection (ECD) is herein proposed for the first time. Exploiting the features of the second generation of flow analysis, termed sequential injection (SI), the smart integration of SI and µ-EME-ECD enables (i) the repeatable formation of microvolumes of phases for the extraction step in a membrane-less (nonsupported) arrangement, (ii) diverting the acceptor plug to the ECD sensing device, (iii) in-line pH adjustment before the detection step, and (iv) washing of the platform for efficient removal of remnants of wetting film solvent, all entirely unsupervised. The real-life applicability of the miniaturized sensing system is studied for in-line sample cleanup and ECD of diclofenac as a model analyte after µ-EME of urine as a complex biological sample. A comprehensive study of the merits and the limitations of µ-EME solvents on ECD is presented. Under the optimal experimental conditions using 14 µL of unprocessed urine as the donor, 14 µL of 1-nonanol as the organic phase, and 14 µL of 25 mM NaOH as the acceptor in a 2.4 mm ID PTFE tubing, an extraction voltage of 250 V, and an extraction time of 10 min, an absolute (mass) extraction recovery of 48% of diclofenac in urine is obtained. The proposed flow-through system is proven to efficiently remove the interfering effect of predominantly occurring organic species in human urine on ECD with RSD% less than 8.6%.


Subject(s)
Diclofenac , Membranes, Artificial , Humans
8.
Food Chem ; 382: 132344, 2022 Jul 15.
Article in English | MEDLINE | ID: mdl-35144191

ABSTRACT

This study developed an electrocolorimetric extraction technique as a simple, rapid, and green method for the simultaneous preconcentration and determination of Ni(II) in chocolate samples. The system was designed using an agarose gel (3% w/v) solution containing 10% v/v 80 mM dimethylglyoxime (DMG) and 10% v/v 0.03 M ammonia as colorimetric reagents to determine Ni(II) ions. When voltage was applied to the system, Ni(II) ions were extracted from the donor solution into the gel and formed Ni-DMG complexes with a pink color. Under the optimal conditions, a good linear range was obtained from 30 to 750 µg L-1 (R2 > 0.998) with a detection limit of 1 µg L-1. Inter- and intra-assay results showing relative standard deviations were less than 2.6% and 1.9%, respectively. Our developed method was applied to determine Ni(II) in chocolate samples. The results were in agreement with those obtained using ICP-OES.


Subject(s)
Chocolate , Food Analysis , Colorimetry , Ions
9.
Talanta ; 235: 122715, 2021 Dec 01.
Article in English | MEDLINE | ID: mdl-34517583

ABSTRACT

A total integrated electrocolorimetric sensing approach consisting of gel-based electromembrane extraction and colorimetric detection in a one-step process was developed. This system was designed using colorimetric reagents preadded to the agarose gel for the determination of the following two model analytes: iodide and hexavalent chromium [Cr(VI)]. In this system, when a voltage was applied, the analytes were extracted and transferred from the sample solution (donor phase) to the gel (acceptor phase). The analytes then simultaneously reacted with the colorimetric reagents inside the gel, yielding blue and violet colors for iodide and Cr(VI), respectively. These colors were then analyzed using a portable spectrometer and could also be distinguished with the naked eye. Parameters affecting the extraction efficiency were studied and optimized for both analytes. The gel composition for iodide detection was 4% (w/v) agarose, 5% (v/v) H2O2, and 1% (w/v) starch in 2 mM HCl. The gel composition for Cr(VI) detection was 2% (w/v) agarose and 1% (w/v) DPC in 0.5 mM HNO3. Both analytes were extracted at an applied potential of 50 V, an extraction time of 15 min and a stirring rate of 600 rpm. Under the optimized conditions, the developed systems provided linear responses within 15 min for iodide concentrations ranging from 50 to 250 µg L-1 with a detection limit of 18 µg L-1 and for Cr(VI) concentrations ranging from 30 to 125 µg L-1 with a detection limit of 5 µg L-1. Finally, these systems were successfully applied to the determination of iodide in iodide food supplement samples and Cr(VI) in drinking water samples, showing a negligible matrix effect. This integration could also be extended to other analytes and detection systems to develop sensitive, on-site, and environmentally friendly sensing approaches.


Subject(s)
Hydrogen Peroxide , Iodides , Chromium , Hydrogen-Ion Concentration , Ions
10.
Biomed Res Int ; 2021: 6689568, 2021.
Article in English | MEDLINE | ID: mdl-34471640

ABSTRACT

Cancer chemotherapies may result in resistance, and therefore, contemporary treatments including natural products may find an increasing consideration. As per Persian medicine (PM), many natural products have been used for malignant and chronic diseases. Triphala, with a combination of Terminalia chebula Retz., Terminalia bellirica Retz., Phyllanthus emblica L., and honey, is a multi-ingredient traditional formulation attributed to anticancer activities in PM. This study is aimed at evaluating the cytotoxic activity of this preparation on HepG2, the human liver cancer cell line. Hydroalcoholic extracts were prepared from the formulation and its components. Compared with the control and Cisplatin, the extracts were tested using MTT assay at different concentrations. All concentrations of the preparation, as well as Cisplatin, were effective significantly against HepG2 cells. All extract preparations at multiple concentrations were significantly effective as evidenced by MTT assay when compared to the control group. The IC50 level for Triphala extract was 77.63 ± 4.3 µg/ml. Based on the results, Triphala and its components have cytotoxic activity on the HepG2 cancer cell line and they can reduce the survival rate significantly.


Subject(s)
Cisplatin/pharmacology , Liver Neoplasms/drug therapy , Phytotherapy/methods , Plant Extracts/pharmacology , Antineoplastic Agents, Phytogenic/pharmacology , Cell Line, Tumor , Cell Survival/drug effects , Humans , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Medicine, Ayurvedic , Plant Extracts/chemistry
11.
Biosens Bioelectron ; 194: 113574, 2021 Dec 15.
Article in English | MEDLINE | ID: mdl-34474275

ABSTRACT

Microfluidic paper-based analytical devices (µPADs) have attracted much attention over the past decade. They embody many advantages, such as abundance, portability, cost-effectiveness, and ease of fabrication, making them superior for clinical diagnostics, environmental monitoring, and food safety assurance. Despite these advantages, µPADs lack the high sensitivity to detect many analytes at trace levels than other commercial analytical instruments such as mass spectrometry. Therefore, a preconcentration step is required to enhance their sensitivity. This review focuses on the techniques used to separate and preconcentrate the analytes onto the µPADs, such as ion concentration polarization, isotachophoresis, and field amplification sample stacking. Other separations and preconcentration techniques, including liquid-solid and liquid-liquid extractions coupled with µPADs, are also reviewed and discussed. In addition, the fabrication methods, advantages, disadvantages, and the performance evaluation of the µPADs concerning their precision and accuracy were highlighted and critically assessed. Finally, the challenges and future perspectives have been discussed.


Subject(s)
Biosensing Techniques , Isotachophoresis , Environmental Monitoring , Lab-On-A-Chip Devices , Mass Spectrometry
12.
Biomed Res Int ; 2021: 5577594, 2021.
Article in English | MEDLINE | ID: mdl-34235220

ABSTRACT

OBJECTIVE: Alzheimer's disease is a progressive, age-related, and neurodegenerative disease characterized by mental decline. The exact cause of Alzheimer's disease is unclear, but cholinergic dysfunction, protein accumulation, and oxidative stress are among the most important hypotheses. The main purpose of our study was to investigate the effects of aqueous and hydroalcoholic extract combination of these two medicinal plants, black pepper and cumin (as a related formulation in traditional Persian medicine), on memory and learning of an immobilized stress animal model. METHODS: In this study, hydroalcoholic and aqueous extracts of cumin and black pepper fruits were prepared. Six groups of mice were treated orally for 2 weeks: control group, immobility stress, and stress-induced immobility mice received different doses of the hydroalcoholic extract (100 and 200 mg/kg) and aqueous extract (100 and 200 mg/kg). The shuttle box, novel object detection, and rotarod test were used to evaluate memory and learning. The activities of acetylcholinesterase, catalase (CAT), and superoxide dismutase (SOD) and the level of reduced glutathione (GSH) and malondialdehyde (MDA) were measured in the brain tissue. RESULTS: Immobility stress significantly reduced learning and motor coordination. Furthermore, MDA levels and acetylcholinesterase activity were significantly increased, while CAT and SOD activities were significantly reduced in the brain of immobility-induced stress mice. Other findings indicated that hydroalcoholic and aqueous extracts (100 and 200 mg/kg) of cumin and black pepper fruits have an improving effect on animal motor coordination and learning ability, GSH content, and CAT, SOD, and acetylcholinesterase enzyme function in comparison with stress groups (p < 0.05). CONCLUSION: The hydroalcoholic and aqueous extracts of cumin and black pepper fruits have protective effects against stress-induced memory deficit and oxidative stress and may have beneficial therapeutic effect in the treatment of neurodegenerative diseases.


Subject(s)
Alzheimer Disease/drug therapy , Apiaceae/metabolism , Memory Disorders/drug therapy , Piper nigrum/metabolism , Acetylcholinesterase/metabolism , Alcohols/chemistry , Animals , Avoidance Learning , Capsicum/chemistry , Catalase/metabolism , Cuminum/chemistry , Disease Models, Animal , Glutathione/metabolism , Immobilization , Iran , Lipid Peroxidation , Medicine, Traditional , Mice , Oxidative Stress , Plant Extracts/pharmacology , Stress, Mechanical , Stress, Psychological , Superoxide Dismutase/metabolism
13.
Am J Alzheimers Dis Other Demen ; 32(7): 429-437, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28683559

ABSTRACT

Herbal medicines for the treatment of Alzheimer's disease (AD) have attracted considerable attention nowadays. Alzheimer's disease is described in traditional Persian medicine (TPM) by the term Nesyan. In this study, 5 main medicinal medieval Persian manuscripts were reviewed to filter plants reported for the treatment of Nesyan. Databases were searched for related possible mechanisms of action of these medicinal plants. Each herb was searched for along with these keywords: "acetyl and butyryl cholinesterase inhibition," "antioxidant," "anti-inflammatory," and "anti-amyloidogenic." In Total, 44 herbs were used for the treatment of Nesyan; 40 of those were authenticated. Also, 30 plants had at least one of the mechanisms of action that were searched for or related pharmacological functions known for the treatment of AD. In this work, we introduce promising candidates in TPM that could undergo further investigation for identification of their active compounds and clinical validation in the treatment of AD.


Subject(s)
Alzheimer Disease/drug therapy , Antioxidants/therapeutic use , Medicine, Traditional , Plants, Medicinal , Humans , Iran , Phytotherapy
14.
Electrophoresis ; 36(2): 305-11, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25262990

ABSTRACT

Introducing a new class of chiral selectors is an interesting work and this issue is still one of the hot topics in separation science and chirality. In this study, for the first time, sulfated maltodextrin (MD) was synthesized as a new anionic chiral selector and then it was successfully applied for the enantioseparation of five basic drugs (amlodipine, hydroxyzine, fluoxetine, tolterodine, and tramadol) as model chiral compounds using CE. This chiral selector has two recognition sites: a helical structure and a sulfated group which contribute to three corresponding driving forces; inclusion complexation, electrostatic interaction, and hydrogen binding. Under the optimized condition (buffer solution: 50 mM phosphate (pH 3.0) and 2% w/v sulfated MD; applied voltage: 18 kV; temperature: 20°C), baseline enantioseparation was observed for all mentioned chiral drugs. When instead of sulfated MD neutral MD was used under the same condition, no enantioseparation was observed which means the resolution power of sulfated MD is higher than neutral MD due to the electrostatic interaction between sulfated groups and protonated chiral drugs. Also, the countercurrent mobility of negatively charged MD (sulfated MD) allows more interactions between the chiral selector and chiral drugs and this in turn results in a successful resolution for the enantiomers. Furthermore, a higher concentration of neutral MD (approximately five times) is necessary to achieve the equivalent resolution compared with the negatively charged MD.


Subject(s)
Electrophoresis, Capillary/methods , Pharmaceutical Preparations/analysis , Pharmaceutical Preparations/chemistry , Polysaccharides/chemistry , Amlodipine/analysis , Anions , Benzhydryl Compounds/analysis , Buffers , Cresols/analysis , Electrophoresis, Capillary/instrumentation , Fluoxetine/analysis , Hydrogen-Ion Concentration , Hydroxyzine/analysis , Phenylpropanolamine/analysis , Phosphates , Spectroscopy, Fourier Transform Infrared , Stereoisomerism , Sulfates/chemistry , Temperature , Tolterodine Tartrate , Tramadol/analysis
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