A new polymeric deep eutectic solvent (DES) composed of poly (2-hydroxyethyl methacrylate):1tetra... more A new polymeric deep eutectic solvent (DES) composed of poly (2-hydroxyethyl methacrylate):1tetradecanol ([PHEMA]:[TD]) was prepared through thermally-induced free-radical polymerization using azobisisobutyronitrile (AIBN) as initiator. The [PHEMA]:[TD] DES was mixed with polyamide 6 (PA6) and electrospun into a composite fibrous scaffold for the first time. The PA6/[HEMA]:[TD] nanofibers were characterized by ATR-FTIR, SEM, BET, and BJH techniques and applied as a sorbent in the micro-solid phase extraction (lSPE) step of pesticide residues from cereal flour samples. The analyses were carried out with the GC-MS technique. The effect of sorbent mass, desorption solvent (kind and volume), pH, and ionic strength was investigated to establish the optimal conditions. Besides, the factors influencing the performance of the electrospinning process, such as electrospinning voltage, polymer solution feed rate, syringe needle tip-to-collector distance, and electrospinning duration, were also optimized. Matrix-matched calibration curves showed good linearity (r 2 = 0.9803-0.9984) in the concentration range of 0.016-250 lg kg À1. The obtained limits of quantification (0.016-1.805 lg kg À1) were lower than the maximum residue levels (MRLs) established by the European Union and the Food and Agriculture Organization (0.01-0.05 mg kg À1) for the pesticide residues in cereal samples. The intra-day and interday precision based on relative standard deviation (RSD) were obtained as 1.1-5.8% and 2.4-8.5%, respectively. The method was applied to the detection of multiclass pesticide residues in maize, rice, wheat, and pastry flour samples, and the obtained relative recoveries were in the range of 71-118% (RSD%<7.5). Finally, the procedure greenness was evaluated based on Complex Green Analytical Procedure Index (Complex GAPI) and the Analytical Eco-Scale (AEC) approaches. This paper also suggests the first application of green hydrophobic PA6/[PHEMA]:[TD] electrospun nanofibers as sorbent for analyzing pesticides in different cereal samples.
Chlorobenzenes (CBs) are persistent and potentially have a carcinogenic effect on mammals. Thus, ... more Chlorobenzenes (CBs) are persistent and potentially have a carcinogenic effect on mammals. Thus, the determination of CBs is essential for human health. Hence, in this study, novel polyurethane–polysulfone/calix[4]arene (PU-PSU/calix[4]arene) nanofibers were synthesized using an electrospinning approach over in-situ coating on a stainless-steel wire. The nanosorbent was comprehensively characterized using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) techniques. The SEM analysis depicted the nanofiber’s unique morphology and size distribution in the range of 50–200 nm. To determine the levels of 1,2,4-trichlorobenzene, 1,2,3-trichlorobenzene, and 1,2,3,4-tetrachlorobenzene in water samples, freshly prepared nanosorbent was employed using headspace-solid phase microextraction (HS-SPME) in combination with gas chromatography micro electron capture detector (GC-µECD). Other calixarenes, such as sulfonated calix[4]arene, p-tert-calixarene, and ca...
Chlorobenzenes (CBs) are persistent and potentially have a carcinogenic effect on mammals.
Thus, ... more Chlorobenzenes (CBs) are persistent and potentially have a carcinogenic effect on mammals. Thus, the determination of CBs is essential for human health. Hence, in this study, novel polyurethane– polysulfone/calix[4]arene (PU-PSU/calix[4]arene) nanofibers were synthesized using an electrospinning approach over in-situ coating on a stainless-steel wire. The nanosorbent was comprehensively characterized using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) techniques. The SEM analysis depicted the nanofiber’s unique morphology and size distribution in the range of 50–200 nm. To determine the levels of 1,2,4-trichlorobenzene, 1,2,3-trichlorobenzene, and 1,2,3,4-tetrachlorobenzene in water samples, freshly prepared nanosorbent was employed using headspace-solid phase microextraction (HS-SPME) in combination with gas chromatography micro electron capture detector (GC-µECD). Other calixarenes, such as sulfonated calix[4]arene, p-tert-calixarene, and calix[6]arene were also examined, and among the fabricated sorbents, the PU–PSU/calix[4]arene showed the highest efficiency. The key variables of the procedure, including ionic strength, extraction temperature, extraction duration, and desorption conditions were examined. Under optimal conditions, the LOD (0.1–1.0 pg mL−1 ), the LDR (0.4–1000 pg mL−1 ), and the R2 > 0.990 were determined. Additionally, the repeatability from fiber to fiber and the intra-day and inter-day reproducibility were determined to be 1.4–6.0, 4.7–10.1, and 0.9–9.7%, respectively. The nanofiber adsorption capacity was found to be 670–720 pg/g for CBs at an initial concentration of 400 pg mL−1 . A satisfactory recovery of 80–106% was attained when the suggested method’s application for detecting chlorobenzenes (CBs) in tap water, river water, sewage water, and industrial water was assessed.
A new polymeric deep eutectic solvent (DES) composed of poly (2-hydroxyethyl methacrylate):1tetra... more A new polymeric deep eutectic solvent (DES) composed of poly (2-hydroxyethyl methacrylate):1tetradecanol ([PHEMA]:[TD]) was prepared through thermally-induced free-radical polymerization using azobisisobutyronitrile (AIBN) as initiator. The [PHEMA]:[TD] DES was mixed with polyamide 6 (PA6) and electrospun into a composite fibrous scaffold for the first time. The PA6/[HEMA]:[TD] nanofibers were characterized by ATR-FTIR, SEM, BET, and BJH techniques and applied as a sorbent in the micro-solid phase extraction (lSPE) step of pesticide residues from cereal flour samples. The analyses were carried out with the GC-MS technique. The effect of sorbent mass, desorption solvent (kind and volume), pH, and ionic strength was investigated to establish the optimal conditions. Besides, the factors influencing the performance of the electrospinning process, such as electrospinning voltage, polymer solution feed rate, syringe needle tip-to-collector distance, and electrospinning duration, were also optimized. Matrix-matched calibration curves showed good linearity (r 2 = 0.9803-0.9984) in the concentration range of 0.016-250 lg kg À1. The obtained limits of quantification (0.016-1.805 lg kg À1) were lower than the maximum residue levels (MRLs) established by the European Union and the Food and Agriculture Organization (0.01-0.05 mg kg À1) for the pesticide residues in cereal samples. The intra-day and interday precision based on relative standard deviation (RSD) were obtained as 1.1-5.8% and 2.4-8.5%, respectively. The method was applied to the detection of multiclass pesticide residues in maize, rice, wheat, and pastry flour samples, and the obtained relative recoveries were in the range of 71-118% (RSD%<7.5). Finally, the procedure greenness was evaluated based on Complex Green Analytical Procedure Index (Complex GAPI) and the Analytical Eco-Scale (AEC) approaches. This paper also suggests the first application of green hydrophobic PA6/[PHEMA]:[TD] electrospun nanofibers as sorbent for analyzing pesticides in different cereal samples.
A new solid phase micro extraction (SPME) fiber coating composed of electrospun polyethylene ter... more A new solid phase micro extraction (SPME) fiber coating composed of electrospun polyethylene terephthalate (PET) nanofibrous mat doped with superhydrophobic nanosilica (SiO2 ) was coated on a stainless-steel wire without the need of a binder. The coating was characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectrometer (FTIR) techniques and it was used in headspace-SPME of 16 organochlorine pesticides in water samples prior to gass chromatography micro electron capture detector (GC-µECD) analysis. The effects of main factors such as adsorption composition, electrospinning flow rate, salt concentration, extraction temperature, extraction time, and desorption conditions were investigated. Under the optimum conditions, the linear dynamic range (8–1000 ng L−1 , R2 > 0.9907), limits of detection (3–80 ng L−1 ), limits of quantification (8–200 ng L−1 ), intra-day and inter-day precisions (at 400 and 1000 ng L−1 , 1.7–13.8%), and fiber-to-fiber reproducibility (2.4–13.4%) were evaluated. The analysis of spiked tap, sewage, industrial, and mineral water samples for the determination of the analytes resulted in satisfactory relative recoveries (78–120%).
A new polymeric deep eutectic solvent (DES) composed of poly (2-hydroxyethyl methacrylate):1tetra... more A new polymeric deep eutectic solvent (DES) composed of poly (2-hydroxyethyl methacrylate):1tetradecanol ([PHEMA]:[TD]) was prepared through thermally-induced free-radical polymerization using azobisisobutyronitrile (AIBN) as initiator. The [PHEMA]:[TD] DES was mixed with polyamide 6 (PA6) and electrospun into a composite fibrous scaffold for the first time. The PA6/[HEMA]:[TD] nanofibers were characterized by ATR-FTIR, SEM, BET, and BJH techniques and applied as a sorbent in the micro-solid phase extraction (lSPE) step of pesticide residues from cereal flour samples. The analyses were carried out with the GC-MS technique. The effect of sorbent mass, desorption solvent (kind and volume), pH, and ionic strength was investigated to establish the optimal conditions. Besides, the factors influencing the performance of the electrospinning process, such as electrospinning voltage, polymer solution feed rate, syringe needle tip-to-collector distance, and electrospinning duration, were also optimized. Matrix-matched calibration curves showed good linearity (r 2 = 0.9803-0.9984) in the concentration range of 0.016-250 lg kg À1. The obtained limits of quantification (0.016-1.805 lg kg À1) were lower than the maximum residue levels (MRLs) established by the European Union and the Food and Agriculture Organization (0.01-0.05 mg kg À1) for the pesticide residues in cereal samples. The intra-day and interday precision based on relative standard deviation (RSD) were obtained as 1.1-5.8% and 2.4-8.5%, respectively. The method was applied to the detection of multiclass pesticide residues in maize, rice, wheat, and pastry flour samples, and the obtained relative recoveries were in the range of 71-118% (RSD%&lt;7.5). Finally, the procedure greenness was evaluated based on Complex Green Analytical Procedure Index (Complex GAPI) and the Analytical Eco-Scale (AEC) approaches. This paper also suggests the first application of green hydrophobic PA6/[PHEMA]:[TD] electrospun nanofibers as sorbent for analyzing pesticides in different cereal samples.
Chlorobenzenes (CBs) are persistent and potentially have a carcinogenic effect on mammals. Thus, ... more Chlorobenzenes (CBs) are persistent and potentially have a carcinogenic effect on mammals. Thus, the determination of CBs is essential for human health. Hence, in this study, novel polyurethane–polysulfone/calix[4]arene (PU-PSU/calix[4]arene) nanofibers were synthesized using an electrospinning approach over in-situ coating on a stainless-steel wire. The nanosorbent was comprehensively characterized using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) techniques. The SEM analysis depicted the nanofiber’s unique morphology and size distribution in the range of 50–200 nm. To determine the levels of 1,2,4-trichlorobenzene, 1,2,3-trichlorobenzene, and 1,2,3,4-tetrachlorobenzene in water samples, freshly prepared nanosorbent was employed using headspace-solid phase microextraction (HS-SPME) in combination with gas chromatography micro electron capture detector (GC-µECD). Other calixarenes, such as sulfonated calix[4]arene, p-tert-calixarene, and ca...
Chlorobenzenes (CBs) are persistent and potentially have a carcinogenic effect on mammals.
Thus, ... more Chlorobenzenes (CBs) are persistent and potentially have a carcinogenic effect on mammals. Thus, the determination of CBs is essential for human health. Hence, in this study, novel polyurethane– polysulfone/calix[4]arene (PU-PSU/calix[4]arene) nanofibers were synthesized using an electrospinning approach over in-situ coating on a stainless-steel wire. The nanosorbent was comprehensively characterized using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) techniques. The SEM analysis depicted the nanofiber’s unique morphology and size distribution in the range of 50–200 nm. To determine the levels of 1,2,4-trichlorobenzene, 1,2,3-trichlorobenzene, and 1,2,3,4-tetrachlorobenzene in water samples, freshly prepared nanosorbent was employed using headspace-solid phase microextraction (HS-SPME) in combination with gas chromatography micro electron capture detector (GC-µECD). Other calixarenes, such as sulfonated calix[4]arene, p-tert-calixarene, and calix[6]arene were also examined, and among the fabricated sorbents, the PU–PSU/calix[4]arene showed the highest efficiency. The key variables of the procedure, including ionic strength, extraction temperature, extraction duration, and desorption conditions were examined. Under optimal conditions, the LOD (0.1–1.0 pg mL−1 ), the LDR (0.4–1000 pg mL−1 ), and the R2 > 0.990 were determined. Additionally, the repeatability from fiber to fiber and the intra-day and inter-day reproducibility were determined to be 1.4–6.0, 4.7–10.1, and 0.9–9.7%, respectively. The nanofiber adsorption capacity was found to be 670–720 pg/g for CBs at an initial concentration of 400 pg mL−1 . A satisfactory recovery of 80–106% was attained when the suggested method’s application for detecting chlorobenzenes (CBs) in tap water, river water, sewage water, and industrial water was assessed.
A new polymeric deep eutectic solvent (DES) composed of poly (2-hydroxyethyl methacrylate):1tetra... more A new polymeric deep eutectic solvent (DES) composed of poly (2-hydroxyethyl methacrylate):1tetradecanol ([PHEMA]:[TD]) was prepared through thermally-induced free-radical polymerization using azobisisobutyronitrile (AIBN) as initiator. The [PHEMA]:[TD] DES was mixed with polyamide 6 (PA6) and electrospun into a composite fibrous scaffold for the first time. The PA6/[HEMA]:[TD] nanofibers were characterized by ATR-FTIR, SEM, BET, and BJH techniques and applied as a sorbent in the micro-solid phase extraction (lSPE) step of pesticide residues from cereal flour samples. The analyses were carried out with the GC-MS technique. The effect of sorbent mass, desorption solvent (kind and volume), pH, and ionic strength was investigated to establish the optimal conditions. Besides, the factors influencing the performance of the electrospinning process, such as electrospinning voltage, polymer solution feed rate, syringe needle tip-to-collector distance, and electrospinning duration, were also optimized. Matrix-matched calibration curves showed good linearity (r 2 = 0.9803-0.9984) in the concentration range of 0.016-250 lg kg À1. The obtained limits of quantification (0.016-1.805 lg kg À1) were lower than the maximum residue levels (MRLs) established by the European Union and the Food and Agriculture Organization (0.01-0.05 mg kg À1) for the pesticide residues in cereal samples. The intra-day and interday precision based on relative standard deviation (RSD) were obtained as 1.1-5.8% and 2.4-8.5%, respectively. The method was applied to the detection of multiclass pesticide residues in maize, rice, wheat, and pastry flour samples, and the obtained relative recoveries were in the range of 71-118% (RSD%<7.5). Finally, the procedure greenness was evaluated based on Complex Green Analytical Procedure Index (Complex GAPI) and the Analytical Eco-Scale (AEC) approaches. This paper also suggests the first application of green hydrophobic PA6/[PHEMA]:[TD] electrospun nanofibers as sorbent for analyzing pesticides in different cereal samples.
A new solid phase micro extraction (SPME) fiber coating composed of electrospun polyethylene ter... more A new solid phase micro extraction (SPME) fiber coating composed of electrospun polyethylene terephthalate (PET) nanofibrous mat doped with superhydrophobic nanosilica (SiO2 ) was coated on a stainless-steel wire without the need of a binder. The coating was characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectrometer (FTIR) techniques and it was used in headspace-SPME of 16 organochlorine pesticides in water samples prior to gass chromatography micro electron capture detector (GC-µECD) analysis. The effects of main factors such as adsorption composition, electrospinning flow rate, salt concentration, extraction temperature, extraction time, and desorption conditions were investigated. Under the optimum conditions, the linear dynamic range (8–1000 ng L−1 , R2 > 0.9907), limits of detection (3–80 ng L−1 ), limits of quantification (8–200 ng L−1 ), intra-day and inter-day precisions (at 400 and 1000 ng L−1 , 1.7–13.8%), and fiber-to-fiber reproducibility (2.4–13.4%) were evaluated. The analysis of spiked tap, sewage, industrial, and mineral water samples for the determination of the analytes resulted in satisfactory relative recoveries (78–120%).
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Papers by hamid najarzadegan
Thus, the determination of CBs is essential for human health. Hence, in this study, novel polyurethane–
polysulfone/calix[4]arene (PU-PSU/calix[4]arene) nanofibers were synthesized using an electrospinning
approach over in-situ coating on a stainless-steel wire. The nanosorbent was comprehensively characterized using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR)
techniques. The SEM analysis depicted the nanofiber’s unique morphology and size distribution
in the range of 50–200 nm. To determine the levels of 1,2,4-trichlorobenzene, 1,2,3-trichlorobenzene,
and 1,2,3,4-tetrachlorobenzene in water samples, freshly prepared nanosorbent was employed using
headspace-solid phase microextraction (HS-SPME) in combination with gas chromatography micro electron capture detector (GC-µECD). Other calixarenes, such as sulfonated calix[4]arene, p-tert-calixarene,
and calix[6]arene were also examined, and among the fabricated sorbents, the PU–PSU/calix[4]arene
showed the highest efficiency. The key variables of the procedure, including ionic strength, extraction
temperature, extraction duration, and desorption conditions were examined. Under optimal conditions,
the LOD (0.1–1.0 pg mL−1
), the LDR (0.4–1000 pg mL−1
), and the R2 > 0.990 were determined. Additionally, the repeatability from fiber to fiber and the intra-day and inter-day reproducibility were determined
to be 1.4–6.0, 4.7–10.1, and 0.9–9.7%, respectively. The nanofiber adsorption capacity was found to be
670–720 pg/g for CBs at an initial concentration of 400 pg mL−1
. A satisfactory recovery of 80–106%
was attained when the suggested method’s application for detecting chlorobenzenes (CBs) in tap water,
river water, sewage water, and industrial water was assessed.
) was coated
on a stainless-steel wire without the need of a binder. The coating was characterized by scanning
electron microscopy (SEM) and Fourier transform infrared spectrometer (FTIR) techniques and it
was used in headspace-SPME of 16 organochlorine pesticides in water samples prior to gass chromatography micro electron capture detector (GC-µECD) analysis. The effects of main factors such
as adsorption composition, electrospinning flow rate, salt concentration, extraction temperature,
extraction time, and desorption conditions were investigated. Under the optimum conditions, the
linear dynamic range (8–1000 ng L−1
, R2 > 0.9907), limits of detection (3–80 ng L−1
), limits of quantification (8–200 ng L−1
), intra-day and inter-day precisions (at 400 and 1000 ng L−1
, 1.7–13.8%),
and fiber-to-fiber reproducibility (2.4–13.4%) were evaluated. The analysis of spiked tap, sewage,
industrial, and mineral water samples for the determination of the analytes resulted in satisfactory
relative recoveries (78–120%).
Thus, the determination of CBs is essential for human health. Hence, in this study, novel polyurethane–
polysulfone/calix[4]arene (PU-PSU/calix[4]arene) nanofibers were synthesized using an electrospinning
approach over in-situ coating on a stainless-steel wire. The nanosorbent was comprehensively characterized using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR)
techniques. The SEM analysis depicted the nanofiber’s unique morphology and size distribution
in the range of 50–200 nm. To determine the levels of 1,2,4-trichlorobenzene, 1,2,3-trichlorobenzene,
and 1,2,3,4-tetrachlorobenzene in water samples, freshly prepared nanosorbent was employed using
headspace-solid phase microextraction (HS-SPME) in combination with gas chromatography micro electron capture detector (GC-µECD). Other calixarenes, such as sulfonated calix[4]arene, p-tert-calixarene,
and calix[6]arene were also examined, and among the fabricated sorbents, the PU–PSU/calix[4]arene
showed the highest efficiency. The key variables of the procedure, including ionic strength, extraction
temperature, extraction duration, and desorption conditions were examined. Under optimal conditions,
the LOD (0.1–1.0 pg mL−1
), the LDR (0.4–1000 pg mL−1
), and the R2 > 0.990 were determined. Additionally, the repeatability from fiber to fiber and the intra-day and inter-day reproducibility were determined
to be 1.4–6.0, 4.7–10.1, and 0.9–9.7%, respectively. The nanofiber adsorption capacity was found to be
670–720 pg/g for CBs at an initial concentration of 400 pg mL−1
. A satisfactory recovery of 80–106%
was attained when the suggested method’s application for detecting chlorobenzenes (CBs) in tap water,
river water, sewage water, and industrial water was assessed.
) was coated
on a stainless-steel wire without the need of a binder. The coating was characterized by scanning
electron microscopy (SEM) and Fourier transform infrared spectrometer (FTIR) techniques and it
was used in headspace-SPME of 16 organochlorine pesticides in water samples prior to gass chromatography micro electron capture detector (GC-µECD) analysis. The effects of main factors such
as adsorption composition, electrospinning flow rate, salt concentration, extraction temperature,
extraction time, and desorption conditions were investigated. Under the optimum conditions, the
linear dynamic range (8–1000 ng L−1
, R2 > 0.9907), limits of detection (3–80 ng L−1
), limits of quantification (8–200 ng L−1
), intra-day and inter-day precisions (at 400 and 1000 ng L−1
, 1.7–13.8%),
and fiber-to-fiber reproducibility (2.4–13.4%) were evaluated. The analysis of spiked tap, sewage,
industrial, and mineral water samples for the determination of the analytes resulted in satisfactory
relative recoveries (78–120%).