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Transition metal carbides, nitrides, and carbonitrides, known as MXenes, are attracting attention for their potential application in trace detection of heavy metals. This study presents diethylenetriamine-functionalized Ti3C2 MXene for trace detection of cadmium and lead ions. Functionalization of Ti3C2 significantly improves the adsorption properties of MXenes by replacing native functional groups with silane moieties that contain three amine groups, offering higher affinity for heavy metals. We demonstrate the efficacy of this material as a solid-phase extractor in column-based solid-phase extraction for heavy metal analysis in various food samples. Diethylenetriamine-functionalized Ti3C2 coupled with the flame atomic absorption spectrometer exhibits exceptional analytical performance. While maintaining a robust stability for 15 adsorption-desorption cycles, the proposed method shows detection limits of 0.09 ng mL-1 for cadmium and 1.7 ng mL-1 for lead, with a linear dynamic range of 0.3-50 ng mL-1 for cadmium and 5-90 ng mL-1 for lead, and relative recoveries of 97.50-101.05 and 98.65-100.80% for cadmium and lead ions, respectively. Additionally, relative standard deviations and enrichment factors were calculated as 0.60-4.70% and 42.3 for cadmium ions and 0.65-1.24% and 44.2 for lead ions.
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Monolayers of Ti3C2Tx MXene and bilayer structures formed by partially overlapping monolayer flakes exhibit opposite sensing responses to a large scope of molecular analytes. When exposed to reducing analytes, monolayer MXene flakes show increased electrical conductivity, i.e., an n-type behavior, while bilayer structures become less conductive, exhibiting a p-type behavior. On the contrary, both monolayers and bilayers show unidirectional sensing responses with increased resistivity when exposed to oxidizing analytes. The sensing responses of Ti3C2Tx monolayers and bilayers are dominated by entirely different mechanisms. The sensing behavior of MXene monolayers is dictated by the charge transfer from adsorbed molecules and the response direction is consistent with the donor/acceptor properties of the analyte and the intrinsic n-type character of Ti3C2Tx. In contrast, the bilayer MXene structures always show the same response regardless of the donor/acceptor character of the analyte, and the resistivity always increases because of the intercalation of molecules between the Ti3C2Tx layers. This study explains the sensing behavior of bulk MXene sensors based on multiflake assemblies, in which this intercalation mechanism results in universal increase in resistance that for many analytes is seemingly inconsistent with the n-type character of the material. By scaling MXene sensors down from multiflake to single-flake level, we disentangled the charge transfer and intercalation effects and unraveled their contributions. In particular, we show that the charge transfer has a much faster kinetics than the intercalation process. Finally, we demonstrate that the layer-dependent gas sensing properties of MXenes can be employed for the design of sensor devices with enhanced molecular recognition.
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BACKGROUND AND OBJECTIVE: Autosomal recessive genetic disorders pose significant health challenges in regions where consanguineous marriages are prevalent. The utilization of exome sequencing as a frequently employed methodology has enabled a clear delineation of diagnostic efficacy and mode of inheritance within multiplex consanguineous families. However, these aspects remain less elucidated within simplex families. METHODS: In this study involving 12 unrelated simplex Iranian families presenting syndromic autism, we conducted singleton exome sequencing. The identified genetic variants were validated using Sanger sequencing, and for the missense variants in FOXG1 and DMD, 3D protein structure modeling was carried out to substantiate their pathogenicity. To examine the expression patterns of the candidate genes in the fetal brain, adult brain, and muscle, RT-qPCR was employed. RESULTS: In four families, we detected an autosomal dominant gene (FOXG1), an autosomal recessive gene (CHKB), and two X-linked autism genes (IQSEC2 and DMD), indicating diverse inheritance patterns. In the remaining eight families, we were unable to identify any disease-associated genes. As a result, our variant detection rate stood at 33.3% (4/12), surpassing rates reported in similar studies of smaller cohorts. Among the four newly identified coding variants, three are de novo (heterozygous variant p.Trp546Ter in IQSEC2, heterozygous variant p.Ala188Glu in FOXG1, and hemizygous variant p.Leu211Met in DMD), while the homozygous variant p.Glu128Ter in CHKB was inherited from both healthy heterozygous parents. 3D protein structure modeling was carried out for the missense variants in FOXG1 and DMD, which predicted steric hindrance and spatial inhibition, respectively, supporting the pathogenicity of these human mutants. Additionally, the nonsense variant in CHKB is anticipated to influence its dimerization - crucial for choline kinase function - and the nonsense variant in IQSEC2 is predicted to eliminate three functional domains. Consequently, these distinct variants found in four unrelated individuals with autism are likely indicative of loss-of-function mutations. CONCLUSIONS: In our two syndromic autism families, we discovered variants in two muscular dystrophy genes, DMD and CHKB. Given that DMD and CHKB are recognized for their participation in the non-cognitive manifestations of muscular dystrophy, it indicates that some genes transcend the boundary of apparently unrelated clinical categories, thereby establishing a novel connection between ASD and muscular dystrophy. Our findings also shed light on the complex inheritance patterns observed in Iranian consanguineous simplex families and emphasize the connection between autism spectrum disorder and muscular dystrophy. This underscores a likely genetic convergence between neurodevelopmental and neuromuscular disorders.
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Consanguinidad , Secuenciación del Exoma , Linaje , Humanos , Irán , Masculino , Femenino , Trastorno Autístico/genética , Niño , Factores de Transcripción Forkhead/genética , Proteínas del Tejido Nervioso/genética , Adulto , Síndrome , Exoma/genética , PreescolarRESUMEN
BACKGROUND: Pontocerebellar hypoplasia is an umbrella term describing a heterogeneous group of prenatal neurodegenerative disorders mostly affecting the pons and cerebellum, with 17 types associated with 25 genes. However, some types of PCH lack sufficient information, which highlights the importance of investigating and introducing more cases to further elucidate the clinical, radiological, and biochemical features of these disorders. The aim of this study is to provide an in-depth review of PCH and to identify disease genes and their inheritance patterns in 12 distinct Iranian families with clinically confirmed PCH. METHODS: Cases included in this study were selected based on their phenotypic and genetic information available at the Center for Comprehensive Genetic Services. Whole-exome sequencing (WES) was used to discover the underlying genetic etiology of participants' problems, and Sanger sequencing was utilized to confirm any suspected alterations. We also conducted a comprehensive molecular literature review to outline the genetic features of the various subtypes of PCH. RESULTS: This study classified and described the underlying etiology of PCH into three categories based on the genes involved. Twelve patients also were included, eleven of whom were from consanguineous parents. Ten different variations in 8 genes were found, all of which related to different types of PCH. Six novel variations were reported, including SEPSECS, TSEN2, TSEN54, AMPD2, TOE1, and CLP1. Almost all patients presented with developmental delay, hypotonia, seizure, and microcephaly being common features. Strabismus and elevation in lactate levels in MR spectroscopy were novel phenotypes for the first time in PCH types 7 and 9. CONCLUSIONS: This study merges previously documented phenotypes and genotypes with unique novel ones. Due to the diversity in PCH, we provided guidance for detecting and diagnosing these heterogeneous groups of disorders. Moreover, since certain critical conditions, such as spinal muscular atrophy, can be a differential diagnosis, providing cases with novel variations and clinical findings could further expand the genetic and clinical spectrum of these diseases and help in better diagnosis. Therefore, six novel genetic variants and novel clinical and paraclinical findings have been reported for the first time. Further studies are needed to elucidate the underlying mechanisms and potential therapeutic targets for PCH.
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Enfermedades Cerebelosas , Proteínas Nucleares , Femenino , Embarazo , Humanos , Irán , Genotipo , Fenotipo , MutaciónRESUMEN
MXenes are a large family of two-dimensional materials with a general formula Mn+1XnTz, where M is a transition metal, X = C and/or N, and Tz represents surface functional groups. MXenes are synthesized by etching A-elements from layered MAX phases with a composition of Mn+1AXn. As over 20 different chemical elements were shown to form A-layers in various MAX phases, we propose that they can provide an abundant source of very diverse MXene-based materials. The general strategy for A-modified MXenes relies on the synthesis of Mn+1A'1-xAâ³xXn MAX phase, in which the higher reactivity of the A'-element compared to that of Aâ³ enables its selective etching, resulting in Aâ³-modified Mn+1XnTz. In general, the Aâ³-element could modify the interlayer spaces of MXene flakes in a form of metallic or oxide species, depending on its chemical identity and synthetic conditions. We demonstrate this strategy by synthesizing Sn-modified Ti3C2Tz MXene from the Ti3Al0.75Sn0.25C2 MAX phase, which was used as a model system. Although the incorporation of Sn in the A-layer of Ti3AlC2 decreases the MAX phase reactivity, we developed an etching procedure to completely remove Al and produce Sn-modified Ti3C2Tz MXene. The resulting MXene sheets were of very high quality and exhibited improved environmental stability, which we attribute to the effect of a uniform Sn modification. Finally, we demonstrate a peculiar electrostatic expansion of Sn-modified Ti3C2Tz accordions, which may find interesting applications in MXene-based nano-electromechanical systems. Overall, these results demonstrate that in addition to different combinations of M and X elements in MAX phases, an A-layer also provides opportunities for the synthesis of MXene-based materials.
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Infantile hypotonia with psychomotor retardation and characteristic facies 1 (IHPRF1) is caused by biallelic mutations in the NALCN gene, the major ion channel responsible for the background Na + conduction in neurons. Through whole-exome sequencing (WES), we report three novel homozygous variants in three families, including c.1434 + 1G > A, c.3269G > A, and c.2648G > T, which are confirmed and segregated by Sanger sequencing. Consequently, intron 12's highly conserved splice donor location is disrupted by the pathogenic c.1434 + 1G > A variation, most likely causing the protein to degrade through nonsense-mediated decay (NMD). Subsequently, a premature stop codon is thus generated at amino acid 1090 of the protein as a result of the pathogenic c.3269G > A; p.W1090* variation, resulting in NMD or truncated protein production. Lastly, the missense mutation c.2648G > T; p.G883V can play a critical role in the interplay of functional domains. This study introduces recurrent urinary tract infections for the first time, broadening the phenotypic range of IHPRF1 syndrome in addition to the genotypic spectrum. This trait may result from insufficient bladder emptying, which may be related to the NALCN channelosome's function in background Na + conduction. This work advances knowledge about the molecular genetic underpinnings of IHPRF1 and introduces a novel phenotype through the widespread use of whole exome sequencing.
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Canales de Sodio , Infecciones Urinarias , Humanos , Canales de Sodio/genética , Canales de Sodio/metabolismo , Canales Iónicos/genética , Proteínas de la Membrana/genética , Fenotipo , Mutación Missense , Síndrome , Infecciones Urinarias/genética , Mutación/genéticaRESUMEN
MXenes, two-dimensional transition metal carbides, nitrides, and carbonitrides, are known for their exceptional electronic and mechanical properties. Yet, the experimental efforts toward the realization of MXene-based nanoelectromechanical systems (NEMS) combining electrical and mechanical functionalities of MXenes at the nanoscale remain very limited. Here, we demonstrate a high-yield fabrication of the electromechanical devices based on individual suspended monolayer MXene flakes. We employed Ti3C2Tx, the most popular MXene material to date, that can be produced as high-quality micrometer-scale monolayer flakes with a high electrical conductivity of over 10 000 S cm-1 and a high effective Young's modulus of about 330 GPa. These Ti3C2Tx flakes can be transferred over prefabricated trenches in a Si/Si3N4 substrate at a high yield, potentially enabling fabrication of hundreds of electromechanical devices based on suspended MXene monolayers. We demonstrate very clean, uniform, and well-stretched membranes with different dimensions, with Ti3C2Tx flakes suspended over trenches with gaps ranging from 200 nm to 2 µm. The resulting Ti3C2Tx monolayer membranes were electrostatically actuated, while their vertical displacement was monitored using a tip of an atomic force microscope (AFM). The devices reliably responded to the electrostatic actuation in ambient conditions over multiple cycles and with different measurement parameters, such as AC frequency, AC voltage amplitude, and AFM tip loading force. The demonstration of the high-yield fabrication of working electromechanical devices based on suspended Ti3C2Tx MXene membranes at the ultimate monolayer limit paves the way for the future exploration of the potential of MXenes for NEMS applications.
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Surface functionalization of two-dimensional (2D) transition metal carbides, nitrides, and carbonitrides, also known as MXenes, is a powerful approach for modification of their physical and chemical properties for new applications. In this study, we demonstrate the synthesis of a bifunctional Ti3C2Tx MXene modified with amine and thiol groups through a facile condensation reaction. We successfully employed the resulting NH2/SH-Ti3C2Tx MXene as a solid phase in the ultrasonic-assisted dispersive micro solid-phase extraction (d-µ-SPE) method for the analytical determination of heavy metals at trace levels in food and soil samples. The prepared NH2/SH-Ti3C2Tx MXene showed remarkable performance in the ultrasonic-assisted d-µ-SPE method with limits of detection of 0.12 and 2.30 ng mL-1, with linear dynamic ranges of 0.50-90 µg L-1 and 10-120 µg L-1 for cadmium (Cd2+) and lead (Pb2+) ions, respectively. Furthermore, the extraction efficiencies were greater than 97%, with a relative standard deviation of less than 3% for five separate batch experiments in the determination of 5.0 µg L-1 of Cd2+ and Pb2+. This study shows that NH2/SH-Ti3C2Tx can be used as a simple, rapid, reliable, selective, and sensitive material in the d-µ-SPE method for the trace determination of Cd2+ and Pb2+ in soil and agricultural products. This study demonstrates the utility of MXenes for analytical chemistry and suggests that further advances in methods for the functionalization of MXenes can open new applications for these already exciting materials.
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Cadmio , Metales Pesados , Cadmio/química , Compuestos de Sulfhidrilo , Titanio/química , Aminas , Plomo , Iones , SueloRESUMEN
An antagonistic yeast strain was isolated from the strawberry fruit cv. Paros, and its antifungal properties against Botrytis cinerea causal agent of strawberry grey mold disease were evaluated under in vitro and in vivo experiments. The isolate was tentatively identified as Tetrapisispora sp. strain 111A-NL1 based on phenotypic characteristics and sequence analysis of D1/D2 domains of the 26S rRNA gene. Volatile organic compounds (VOCs) produced by the 111A-NL1 strain inhibited the mycelial growth of fungal pathogen (75.19%) and conidial germination (63.34%); however, inhibition percentage of mycelial growth of pathogen by dual culture test was less (19.49%). Also, the strain produced pectinase, siderophore, chitinase, IAA, as well as gibberellin, and could solubilize phosphate. Additionally, the disease severity of strawberry grey mold was decreased by employing living cells and volatile metabolites methods by 47.61% and 74.05%, respectively, in comparison with untreated control seven days after inoculation. Therefore, its mode of action might consist of antibiosis and VOCs production by yeast strain 111A-NL1 against B. cinerea. The VOCs released by strain 111A-NL1 were analyzed, and thirty-three chemical compounds were determined by gas chromatography-mass spectroscopy (GC-MS). Out of them, Decane (12.79%), Squalene (9.60%), Undecane (7.98%), Benzene, 1,2,3-trimethyl- (7.67%), Nonane, 2,6-dimethyl- (5.69%), Benzene, 1-ethyl-3-methyl- (5.55%), Mesitylene (4.17%), and Phenylethyl Alcohol (3.33%) were the major components. In addition, the selected strain reduced natural decay incidence and weight loss of fruit, and preserved quality parameters of strawberry fruit including firmness, soluble solids content, and titratable acidity. This research averred, for the first time, that the creation of VOCs by Tetrapisispora sp. strain 111A-NL1 could play an essential role as a biofumigant in the antifungal activity against strawberry grey mold.
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Fragaria , Compuestos Orgánicos Volátiles , Antifúngicos/química , Antifúngicos/farmacología , Benceno , Fragaria/metabolismo , Fragaria/microbiología , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Saccharomyces cerevisiae/metabolismo , Compuestos Orgánicos Volátiles/farmacologíaRESUMEN
Two-dimensional (2D) titanium carbide MXene (Ti3C2Tx) has attracted significant attention due to its combination of properties and great promise for various applications. The size of the 2D sheets is a critical parameter affecting multiple properties of assembled films, fibers and 3D structures. The increased lateral size of MXene flakes can benefit not only their assemblies by improving the interflake contacts and alignment but also fundamental studies at the individual flake level, allowing for facile patterning and investigation of intrinsic physical properties of MXenes. Increasing the average size of the parent MAX phase is one of the strategies previously used to increase the flake size of the resultant MXene. Here, we show that the protocol used for the next step of the synthesis procedure, delamination of multilayer MXene into individual nanosheets, significantly affects the lateral size of the resultant flakes. We developed a soft delamination approach, which prevents fracture of flakes and preserves their size. Combining this approach with the large-grain Ti3AlC2 MAX phase precursor, we achieved individual flakes of up to 40 µm in lateral size. These flakes can be used for patterning multiple contacts and fabrication of field-effect transistors for multiprobe electrical characterization and other measurements. These findings indicate the importance of controlling the delamination process in order to achieve large MXene flakes and improve properties of MXene-based materials and devices.
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Objective: Autism spectrum disorder (ASD) is a heterogeneous neuropsychiatric group of pervasive developmental disorders mainly diagnosed through the complex behavioral phenotype. According to strong genetic involvement, detecting the chromosome regions and the key genes linked to autism can help to elucidate its etiology. The present study aimed to investigate the value of cytogenetic analysis in syndromic autism and find an association between autism and chromosome abnormalities. Materials & Methods: Thirty-six autistic patients from 30 families were recruited, clinically diagnosed with the Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5). The syndromic patients with additional clinical features (including development delay, attention deficit, hyperactivity disorder, seizure, and language and intellectual impairment) were selected due to elevating the detection rate. Cytogenetics analysis was performed using GTG banding on the patients' cultured fibroblasts. Moreover, array-comparative genomic hybridization (CGH) was also performed for patients with a de novo and novel variant. Results: Karyotype analysis in 36 syndromic autistic patients detected chromosomal abnormalities in 2 (5.6%) families, including 46,XY,dup(15)(q11.1q11.2) and 46,XX,ins(7)(q11.1q21.3)dn. In the latter, array-CGH detected 3 abnormalities on chromosome 7, including deletion and insertion on both arms: 46,XX,del(7)(q21.11q21.3),dup(7)(p11.2p14.1p12.3)dn. Conclusion: We reported a novel and de novo cytogenetic abnormality on chromosome 7 in an Iranian patient diagnosed with syndromic autism. However, the detection rate in syndromic autism was low, implying that it cannot be utilized as the only diagnostic procedure.
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The authors described a new application of amino-functionalized KIT-6 for dispersive ultrasonication-assisted micro solid phase extraction of hippuric acid (HA) and methyl hippuric acid (MHA) from human urine and water samples. In the first step, an amino-functionalized mesoporous silica of type KIT-6 was synthesized. It was characterized by field emission scanning electron microscopy, Fourier transform infrared spectrometry, nitrogen adsorption-desorption analysis, thermogravimetry and X-ray diffraction. Following sorption and desorption with 1.0 mL methanol/NH4OH (1%; v/v), HA and MHA were quantified by HPLC with UV detection. Various important parameters were optimized by Box-Behnken design. Under optimized conditions, The limit of detections (LOD) were calculated by a signal-to-noise ratio of 3, which were 0.5 µg L-1 and 0.2 µg L-1 for HA and MHA, respectively, and the calibration plot is linear in the 1-1000 µg L-1 concentration range. Only small matrix effects were found. The method was successfully implemented for the sensitive determination of HA and MHA in (spiked) human urine samples. Graphical abstract Schematic of a sorbent for dispersive micro solid phase extraction coupled with ultrasonic power. It consists of amino functionalized KIT-6 and was used for the simultaneous preconcentration and determination of low levels of hippuric and methyl hippuric acid in urine and water samples.
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Due to importance of trace analysis of lead and copper ions because of their toxicity, in this paper, for the first time a unique tetragonal star-like morphology of polyaniline was applied as a efficient solid phase for selective trace separation of copper and lead at optimum experimental conditions in shrimp, fish and water samples. Due to the unique star like nanostructure of synthesized sorbent, the tendency of the sorbent toward selective extraction of lead and copper ion in the optimised pH is very interesting. The prepared polymeric resin displayed good figures of merits with analytical calibration curve ranging from 1 to 120 µg L(-1) for copper and 2 to 100 µg L(-1) for lead ions with limits of detection of 0.4 µg L(-1) for copper and 0.9 µg L(-1) for lead, adsorption capacities of 84 and 110 mg g(-1) for copper and lead ions, respectively, extraction efficiency of greater than 96%, and relative standard deviation (RSD) of less than 4% for eight separate column experiments in determination of 5.0 µg of lead and copper. The obtained data for adsorption capacity of the sorbent shows the high tendency of the sorbent toward the mentioned ions in this nanostructure form. Finally, this sorbent can be used as a simple, rapid, reliable, selective and sensitive method for determination of trace levels of Cu(II) and Pb(II).
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Compuestos de Anilina/química , Nanoestructuras/química , Alimentos Marinos/análisis , Mariscos/análisis , Animales , Peces , Extracción en Fase Sólida/métodos , Espectrofotometría Atómica/métodosRESUMEN
Magnetic molecularly imprinted polymers have been synthesized for the selective preconcentration and trace determination of lamotrigine (LTG) in urine and plasma samples. The magnetic nanoparticles were modified by tetraethyl orthosilicate and 3-methacryloxypropyl trimethoxysilane before imprinting. The magnetic molecularly imprinted polymers were prepared via surface molecular imprinting technique, using Fe3 O4 as a magnetic component, LTG as template molecule, methacrylic acid as a functional monomer, ethylene glycol dimethacrylate as a cross-linker, and 2,2'-azobisisobutyronitrile as a radical initiator in methanol/acetonitrile (50:50, v/v) as the porogen. The obtained sorbent was characterized using scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, and thermal analysis. Separation of the sorbent from the sample solution was simply achieved by applying an external magnetic field. Determination of the extracted drug was performed by high-performance liquid chromatography with UV detection. Under the optimum extraction conditions, the method detection limits were 0.7 µg/L (based on S/N of 3) for urine samples and 0.5 µg/L for plasma samples. A linear dynamic range of 1-1000 µg/L was obtained for LTF in plasma and urine samples. Finally, the applicability of the proposed method was evaluated by extraction and determination of LTG in urine and plasma samples.
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Anticonvulsivantes/aislamiento & purificación , Polímeros/química , Extracción en Fase Sólida/métodos , Triazinas/aislamiento & purificación , Anticonvulsivantes/sangre , Anticonvulsivantes/orina , Humanos , Lamotrigina , Impresión Molecular , Polímeros/síntesis química , Extracción en Fase Sólida/instrumentación , Triazinas/sangre , Triazinas/orinaRESUMEN
A simple, rapid, and efficient sample pretreatment technique, based on solvent-based de-emulsification dispersive liquid-liquid microextraction (SD-DLLME), followed by high performance liquid chromatography (HPLC) has been developed for simultaneous preconcentration and trace detection of 2,4-dichlorophenoxyacetic acid (2,4-D) and 2-methyl-4-chlorophenoxyacetic acid (MCPA) in water and urine samples. Some parameters such as acidity of solution, the amount of salt, type, and volume of extraction solvents, type of disperser/de-emulsifier solvent, and its volume were investigated and optimized. Under optimum extraction conditions, the limits of detections (LODs) of this method for MCPA and 2,4-D were 0.2 and 0.6 µg L(-1) (based on 3S(b)/m) in water and 0.4 and 1.6 µg L(-1) in urine, respectively. Furthermore, dynamic linear range of this method for MCPA and 2,4-D was 1-300 and 2-400 µg L(-1), repectively. Finally, the applicability of the proposed method was evaluated by extraction and determination of the herbicides in urine and different water samples.
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Ácido 2,4-Diclorofenoxiacético/análisis , Ácido 2-Metil-4-clorofenoxiacético/análisis , Herbicidas/análisis , Contaminantes Químicos del Agua/análisis , Ácido 2,4-Diclorofenoxiacético/orina , Ácido 2-Metil-4-clorofenoxiacético/orina , Cromatografía Líquida de Alta Presión , Monitoreo del Ambiente , Herbicidas/orina , Límite de Detección , Microextracción en Fase Líquida , Solventes/química , Orina/química , Contaminantes Químicos del Agua/orinaRESUMEN
A simple, rapid, and efficient method, based on surfactant assisted dispersive liquid-liquid microextraction (SA-DLLME), followed by high performance liquid chromatography (HPLC) has been developed for simultaneous preconcentration and trace detection of zonisamide and carbamazepine in biological samples. A conventional cationic surfactant called cethyltrimethyl ammonium bromide (CTAB) was used as a disperser agent in the proposed approach. 1.5 mL of CTAB (0.45 mmol L(-1)) (disperser solvent) containing 50.0 µL of 1-octanol (extraction solvent) was injected rapidly into the 7.0 mL of water or diluted plasma or urine. A cloudy solution (water, 1-octanol, and CTAB) was formed in the test tube. After formation of cloudy solution, the mixture was centrifuged and 20 µL of collected phase was injected into HPLC for subsequent analysis. Some parameters such as the type and volume of the extraction solvent, the type and concentration of surfactant, pH, ionic strength and centrifugation time were evaluated and optimized. Under optimum extraction conditions, the limits of detections (LODs) were 2.1 and 1.5 µg L(-1) (based on 3Sb/m) for urine samples, and 2.3 and 1.6 µg L(-1) for plasma samples. Linear dynamic range of 5-300 and 5-200 µg L(-1) were obtained for zonisamide and carbamazepine in all samples. Finally, the applicability of the proposed method was evaluated by extraction and determination of the drugs in urine and plasma samples.