Development of microextraction methods for the determination of sulfamethoxazole in water and biological samples: modelling, optimization and verification by central composite design

This study aimed to preconcentration of sulfamethoxazole (SMX) in water and biological samples. Ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) and ultrasound-assisted dispersive solid-phase microextraction (UA-DSPME) methods paired with spectrophotometry were applied to extraction and preconcentration of SMX. ZnFe2O4 nanoparticles were prepared as adsorbent in UA-DSPME method by hydrothermal method. The scanning electron microscopy (SEM) technique showed that the adsorbent had symmetrical, bullet-shaped particles with uniform size. The results of the X-ray diffraction (XRD) showed the successful synthesis of the ZnFe2O4 nanoparticles. Effective parameters in extraction, including ultrasonication time, disperser solvent volume, adsorbent amount, extraction solvent volume, eluent volume, and pH were investigated and optimized. The practical and optimal conditions of the process were determined by the central composite design (CCD). The optimal conditions were 0.024 g of adsorbent, 535 µL of disperser solvent volume, 7.5 min of ultrasonication time, 235 µL of eluent volume, pH of 5, and 185 µL of extraction solvent volume. Linear ranges and detection limits were 20–1,200 μg L−1 and 6 μg L−1 for UA-DSPME and 10–800 μg L−1 and 3 μg L−1 for UA-DLLME. Relative standard deviation (RSD) of less than 4% were obtained for UA-DSPME and UA-DLLME methods. The reusability showed that the ZnFe2O4 adsorbent could extract SMX up to five cycles of adsorption/desorption without significant reduction in its efficiency. Also, interference studies showed that the presence of different cations and anions did not significantly interfere in the extraction of SMX. The outcomes of real-time samples analysis showed that the extraction of SMX for both methods was in the range of 92.44%–99.12%. The results showed the developed methods are simple, sensitive, and suitable for SMX preconcentration in environmental water and biological samples

Synthesis of lignin nanoparticles from Oxytenanthera abyssinica by nanoprecipitation method followed by ultrasonication for the nanocomposite application

Lignin nanoparticles (LNPs) have a wide range of potential uses in the biomedical and environmental fields. They are used to prepare antioxidants, food packaging material, energy storage, cosmetics, thermal/light stabilizers, reinforced materials, and drug delivery. In this study, LNPs were prepared from soda lignin obtained from Oxytenanthera abyssinica using dioxane, acetone, ethanol, and acid-base solvents through the nanoprecipitation method, followed by an ultrasonic process. These methods produced four different LNPs with yields in the range of 28.5% to 88.9%. Scanning electron microscope (SEM) showed that the spherical-shaped LNPS (100–400 nm) were obtained using the acetone solvent, while irregularly shaped LNPs were formed by dioxane (150–400 nm), ethanol (40–200 nm) and acid-base (100–800 nm) solvents. The maximum zeta potential of the LNPAS samples was |-35.1 mV|, determined by the dynamic light scattering (DLS), with a particle size distribution between 91.28 and 458.7 nm. According to the energy-dispersive X-ray spectrometer (EDX) results, the sample contains the elements C, O, Si, Na, and Mo. X-ray powder diffraction (XRD) analysis showed very small crystallinity sizes ranging from 0.31 to 0.35 nm. Proton nuclear magnetic resonance (H-NMR) and Fourier transformation infrared Spectroscopy (FTIR) were used to find the functional groups in the synthesized LNPs. The Thermogravimetric analysis (TGA) peak showed that LNPS was thermally stable, and rapid mass loss occurred between 300 and 415 °C. Differential Scanning Calorimetry (DSC) data shows that the highest exothermic peaks are obtained at 345.2 °C. Synthesis of LNPs by dissolving isolated soda lignin in acetone, ethanol, dioxane, and acid-base solvents was quickly recovered, cheap, and eco-friendly. The synthesized are free of sulfur; they do not use toxic solvents such as Tetrahydrofuran (THF), Dimethyl sulfoxide (DMSO), and Dimethylformamide (DMF). Thus, they provide benefits for high-value-added Nanocomposite applications such as bio-based nonmaterial and food packaging materials. Acid-base nanoprecipitation procedure is the best approach regarding stability and size, but the acetone nanoprecipitation method is preferable regarding shape

Synthesis of lignin nanoparticles from Oxytenanthera abyssinica by nanoprecipitation method followed by ultrasonication for the nanocomposite application

Lignin nanoparticles (LNPs) have a wide range of potential uses in the biomedical and environmental fields. They are used to prepare antioxidants, food packaging material, energy storage, cosmetics, ther-mal/light stabilizers, reinforced materials, and drug delivery. In this study, LNPs were prepared from soda lignin obtained from Oxytenanthera abyssinica using dioxane, acetone, ethanol, and acid-base solvents through the nanoprecipitation method, followed by an ultrasonic process. These methods produced four different LNPs with yields in the range of 28.5% to 88.9%. Scanning electron microscope (SEM) showed that the spherical-shaped LNPS (100-400 nm) were obtained using the acetone solvent, while irregularly shaped LNPs were formed by dioxane (150-400 nm), ethanol (40-200 nm) and acid-base (100-800 nm) solvents. The maximum zeta potential of the LNPAS samples was |-35.1 mV|, determined by the dynamic light scattering (DLS), with a particle size distribution between 91.28 and 458.7 nm. According to the energy-dispersive X-ray spectrometer (EDX) results, the sample contains the elements C, O, Si, Na, and Mo. X-ray powder diffraction (XRD) analysis showed very small crystallinity sizes ranging from 0.31 to 0.35 nm. Proton nuclear magnetic resonance (H-NMR) and Fourier transformation infrared Spectroscopy (FTIR) were used to find the functional groups in the synthesized LNPs. The Thermogravimetric analysis (TGA) peak showed that LNPS was thermally stable, and rapid mass loss occurred between 300 and 415 degrees C. Differential Scanning Calorimetry (DSC) data shows that the highest exothermic peaks are obtained at 345.2 degrees C. Synthesis of LNPs by dissolving isolated soda lignin in acetone, ethanol, dioxane, and acid-base solvents was quickly recovered, cheap, and eco-friendly. The synthesized are free of sulfur; they do not use toxic solvents such as Tetrahydrofuran (THF), Dimethyl sulfoxide (DMSO), and Dimethylformamide (DMF). Thus, they provide benefits for high-value-added Nanocomposite applications such as bio-based nonmaterial and food packaging materials. Acid-base nanoprecipitation procedure is the best approach regarding stability and size, but the acetone nanopre-cipitation method is preferable regarding shape