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1.
Food Chem ; 463(Pt 1): 141098, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39265405

RESUMEN

A simple and effective ultrasound-assisted dispersive micro solid-phase extraction (UA-dµSPE) method was developed for the spectrophotometric determination of traces maneb in food and water. In this study, a new hybrid block copolymer poly (vinyl benzyl chloride-b-dimethyl aminoethyl methacrylate) (Pvb-DMA) was synthesized and characterized using techniques such as FTIR, SEM-EDX. The synthesized Pvb-DMA was used as an adsorbent for the extraction of maneb for first time in this study. The effects of different experimental variables such as pH, adsorbent amount, sample volume, eluent type were optimized. The statistical toll factorial design was applied to estimate the individual and combined impact of parameters on the extraction of maneb. The applicability of different solvents such as acetone, methanol, ethanol, tetrahydrofuran, acetonitrile for maneb recovery from adsorbent was tested. The detection and quantification limits were found to be 3.3 ng mL-1 and 10.0 ng mL-1, respectively. In addition, the preconcentration factor and linear range was obtained 300 and 10-500 ng mL-1. The extraction recovery and relative standard deviation were found to be 95 % and 2.8 %, respectively.

2.
J Food Sci ; 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39218807

RESUMEN

A wide range of active agents, synthetic and natural agents such as essential oils, chitosan and polyphneols consisting of curcumin, gallic acid, anthocyanins, and catechins have been used in order to develop antimicrobial packaging systems, and among them, natural polyphenolic compounds, specially curcumin (Cur) has great potential due to effective biological activities in developing food packaging material. Quercetin (Quer) is also the mostly studied flavonol as a color-changing indicator in the food industry and has been already developed as a realistic alternative for smart and active food packaging. The reason for choosing these two polyphenolic compounds is that they simultaneously possess many beneficial properties such as antioxidant, antibacterial, antiviral, antitumoral, and anti-inflammatory effects. Additionally, the main objective of the study is to combine polypropylene (PP), which is the most preferred and cost-effective polymer in the packaging industry, with these active ingredients, rather than using more expensive polymer types. In this context, PP-Quer or PP-Cur membranes, which are new experiences based on these literatures were chemically characterized by Fourier transform infrared spectroscopy, and the surface morphology of these composite membranes was characterized by scanning electron microscopy. The antibacterial response against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria species was investigated. Furthermore, the reactive oxygen species generation and anticancer activity of these composite membranes using human colorectal adenocarcinoma (HT-29) were observed. We proposed that PP-Quer or PP-Cur composite membranes can be a potential candidate as active packaging material in the food industry.

3.
Food Chem ; 457: 140114, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-38909453

RESUMEN

The aim of this study was to develop a practical orbital shaker-assisted magnetic solid phase extraction (OSA-MSPE) method for the determination of lead by FAAS. A new magnetic poly linoleic acid-polystyrene-polydimethylsiloxane (PSt-PLina-PDMS) hydrophobic graft copolymer was synthesized and characterized by NMR, FT-IR, SEM-EDX, DSC, TGA, BET and used as adsorbent for the extraction of Pb (II). This adsorbent can be used at least 50 times without any decrease of its adsorption properties for the adsorption and elution of analyte ions. Several analytical parameters including pH, adsorbent amount, sample volume, shaking time, etc. were optimized. Multivariate optimization was used for the investigation of different parameters. The linear range at optimum operating condition was 1.7-84 µg L-1. The limit of detection (LOD) and limit of quantification (LOQ) were 0.5 µg L-1, 1.7 µg L-1, respectively. Intraday and interday relative standard deviation (RSD %), enhancement factor (EF) and adsorbent capacity were found as 1.9%, 3.3%, 166.7, 50 mg g-1, respectively. OSA-MSPE method was tested with certified reference materials including LGC-6010 (Hard Drinking Water), NCS ZC73032 Celery and CS-M-3 Control Sample Microelements in Mushroom Powder for the accuracy. Experimental results for lead were confirmed with certified values. Present method was successfully applied to various liquid and solid food samples. The OSA-MSPE method has some important features such as selective, sensitive, low LOD, LOQ and RSD, pre-concentration factor (PF) and high enhancement factor (EF). High tolerance limits against matrix ions were achieved.


Asunto(s)
Contaminación de Alimentos , Plomo , Poliestirenos , Extracción en Fase Sólida , Contaminantes Químicos del Agua , Extracción en Fase Sólida/métodos , Extracción en Fase Sólida/instrumentación , Contaminación de Alimentos/análisis , Plomo/aislamiento & purificación , Plomo/análisis , Plomo/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Poliestirenos/química , Adsorción , Polímeros/química , Ácido Linoleico/análisis , Ácido Linoleico/aislamiento & purificación , Ácido Linoleico/química , Dimetilpolisiloxanos/química , Límite de Detección
4.
Front Chem ; 12: 1367451, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38549839

RESUMEN

This work refers to the synthesis and characterization of poly (3-hydroxybutyrate)-b-oligo (2-ethyl oxazoline) (oligoEtOx). Cationic ring-opening polymerization of 2-ethyl oxazoline yielded poly (2-ethyl oxazoline) (oligoEtOx) with a hydroxyl end. Carboxylic acid-terminated PHB was reacted with oligoEtOx via dicyclohexylcarbodiimide chemistry to obtain PHB-b-oligoEtOx conjugates. The obtained PHB-b-oligoEtOx conjugates were successfully characterized by 1H- and 13C NMR, FTIR, DSC, and size exclusion chromatography. PHB-b-oligoEtOx conjugates can be promising biologic active materials.

5.
Food Chem ; 446: 138871, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38432133

RESUMEN

A new graft copolymer composed of polystyrene and polylinoleic acid (PLinas) with the sodium salt of iminodiacetate (Ida) was synthesized and used as an adsorbent. The vortex-assisted dispersive solid-phase micro-extraction (VA-dSPµE) method was used for the extraction and pre-concentration of chromium. Multivariate methodologies, such as factorial design and 3D surface plots, were applied for screening and optimizing effective extraction parameters. The influence of diverse analytical parameters, such as pH, sample volume, and interfering ions, on the extraction of chromium was studied. The calibration standard curve exhibited a linear range from 0.01 to 0.50 µg L-1. The relative standard deviation and limit of detection were found to be 1.65 % and 0.003 µg L-1, respectively. Extraction recoveries were found in the range of 96 to 99 % by using certified reference materials (CRMs). The adsorbent capacity of PLinas-Ida was found to be 112 mg g-1. The VA-dSPµE method demonstrated its effectiveness in the pre-concentration and determination of chromium within samples of foodstuffs by graphite furnace-atomic absorption spectrometry (GF-AAS).


Asunto(s)
Cromo , Extracción en Fase Sólida , Extracción en Fase Sólida/métodos , Polímeros/química , Microextracción en Fase Sólida/métodos , Espectrofotometría Atómica/métodos
6.
Foods ; 12(19)2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-37835273

RESUMEN

Background: Cadmium (Cd) is a very toxic and carcinogenic heavy metal even at low levels and it is naturally present in water as well as in food. Methods: A new polyvinyl benzyl xanthate (PvbXa) was synthesized and used as a new adsorbent in this work. It contains pendant sulfide groups on the main polystyryl chain. Using this new adsorbent, PvbXa, a vortex-assisted dispersive solid-phase microextraction (VA-dSPµE) procedure was developed for the determination of cadmium from food and water samples via flame atomic absorption spectrophotometry (FAAS). Synthesized PvbXa was characterized by 1H Nuclear magnetic resonance (NMR) Spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), and X-ray Photoelectron Spectroscopy (XPS). The different parameters of pH, sample volume, mixing type and time, sorbent amount, and eluent time were optimized using standard analytical methods. Results: The optimized method for assessment of Cd in food and water samples shows good reliability. The optimum conditions were found to be a 0.20-150 µg L-1 linear range, 0.06 µg L-1 LOD, 0.20 µg L-1 LOQ, 4.3 RSD %, and a preconcentration factor of 160. Conclusions: The statistically experimental variables were utilized using a central composite design (CCD). The present method is a low-cost, simple, sensitive, and very effective tool for the recovery of Cd.

7.
Environ Sci Pollut Res Int ; 30(33): 79904-79915, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37286840

RESUMEN

As a novel adsorbent, an opioid silver-morphine-functionalized polypropylene was synthesized through a one-pot reaction at room temperature and successfully used for the simple one-pot photocatalytic degradation catalyst of methyl orange removal from wastewater. UV spectral analysis reveals a special reference to the excitation of surface plasmon resonance as the main characteristic of the polymer-Ag nanocomposite in toluene solution peak at 420 nm in AgPP-mrp catalyst. The 1H NMR spectrum showed no sign of Ag NP peaks revealing small size distribution in the channels of morphine-functionalized polypropylene polymer. The morphology of silver nanoparticle-doped polymer through scanning electron microscopy (SEM-EDX) reveals PP-mrp with continuous matrix and Ag NPs (0.87 wt%). Furthermore, photocatalytic degradation of methyl orange was investigated on AgPP-mrp catalyst spectrophotometrically under solar irradiation in waste effluent, demonstrating high degradation efficiency. According to experimental findings, silver nanoparticles (AgPP-mrp) achieved high degradation capacities of 139 mg/g equivalent to 97.4% of photodegradation in a little period of time (35 min), as associated with previously stated materials and follow pseudo-second-order kinetic degradation tail of a high regression coefficient (R2 = 0.992). The suggested techniques offer a linear reaction for MO over the pH range of 1.5 to 5 and a degradation temperature of 25 to 60 °C. Central composite design and response surface methodology statistics recommend pH of the reaction medium and time as important variables for methyl orange degradation on AgPP-mrp photocatalytic. AgPP-mrp on the photocatalytic phenomenon based on heterojunction catalytic design producing electron holes (e-), as well as superoxides for the successful degradation of methyl orange.


Asunto(s)
Nanopartículas del Metal , Nanocompuestos , Nanopartículas del Metal/química , Plata/química , Polipropilenos , Morfina , Nanocompuestos/química , Catálisis
8.
Food Chem ; 425: 136523, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37295209

RESUMEN

A new polyoleic acid-polystyrene (PoleS) block/graft copolymer was synthesized and applied as adsorbent for ultrasound assisted dispersive solid phase microextraction (UA-DSPME) of Sb(III) in different bottled beverages and analysis using hydride generation atomic absorption spectrometry (HGAAS). Adsorption capacity of the PoleS was 150 mg g-1. Several sample preparation parameters such as sorbent amount, solvent type, pH, sample volume and shaking time were optimized (based on central composite design (CCD) approach) and evaluated in respect to the recovery of Sb(III). The method revealed a high tolerance limit of matrix ions presence. Under optimized conditions, linearity range, the limit of detection, the limit of quantitation, extraction recovery, enhancement factor, preconcentration factor were 5-800 ng L-1, 1.5 ng L-1, 5.0 ng L-1, 96%, 82, 90, respectively. Accuracy of the UA-DSPME method was confirmed based on different certified reference materials and standard addition method. Factorial design was utilized to estimate the influences of variables of recovery of Sb(III).


Asunto(s)
Microextracción en Fase Líquida , Microextracción en Fase Sólida , Microextracción en Fase Sólida/métodos , Poliestirenos/química , Espectrofotometría Atómica/métodos , Bebidas/análisis , Polímeros/análisis , Límite de Detección
9.
J Microencapsul ; 40(3): 197-215, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36881484

RESUMEN

Current artificial ligaments based on polyethylene terephthalate (PET) are associated with some disadvantages due to their hydrophobicity and low biocompatibility. In this study, we aimed to modify the surface of PET using polyethylene glycol (PEG)-terminated polystyrene (PS)-linoleic nanoparticles (PLinaS-g-PEG-NPs). We accomplished that BMP-2 in two different concentrations encapsulated in nanoparticles with an efficiency of 99.71 ± 1.5 and 99.95 ± 2.8%. While the dynamic contact angle of plain PET surface reduced from 116° to 115° after a measurement periods of 10 s, that of PLinaS-g-PEG-NPs modified PET from 80° to 17.5° within 0.35 s. According to in vitro BMP2 release study, BMP-2 was released 13.12 ± 1.76% and 45.47 ± 1.78% from 0.05 and 0.1BMP2-PLinaS-g-PEG-NPs modified PET at the end of 20 days, respectively. Findings from this study revealed that BMP2-PLinaS-g-PEG-NPs has a great potential to improve the artificial PET ligaments, and could be effectively applied for ACL reconstruction.


Asunto(s)
Ligamento Cruzado Anterior , Nanopartículas , Ligamento Cruzado Anterior/cirugía , Tereftalatos Polietilenos , Proteína Morfogenética Ósea 2
10.
Food Chem ; 403: 134475, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36358104

RESUMEN

A novel one step route for the synthesis of tannic acid, lipoic acid and menthol functionalized polyvinyl chloride, PVC, (PVC-Tann, PVC-Lip, PVC-Mnt) and chlorinated polypropylene, PP-Cl, (PP-Mnt, PP-Lip) was applied imparting antioxidative properties to the newly-formed materials. The resulting modified polymers were characterized by stress-strain mechanical measurement, 1H NMR, gel permeation chromatography (GPC) and thermogravimetric (TGA) analysis. Linseed oil, owing to its high linolenic acid content, was used to track the autoxidation process. The chloride functional groups were reacted with the hydroxyl/carboxylic acid of the natural compounds in the presence of a base. Linseed oil was poured into the natural compound functionalized PVC covered Petri dish to undergo autoxidation under white light. Each of the PVC- and PP-Cl-based polymers was active in delaying autoxidation. The PP-Mnt series and PP-Lip polymers all delayed autoxidation by 8 days over the PP-Cl precursor material. The autoxidation process was further confirmed by monitoring peroxide formation in the exposed linseed oil samples through differential scanning calorimeter (DSC) analysis.


Asunto(s)
Ácido Tióctico , Cloruro de Vinilo , Cloruro de Polivinilo/química , Polipropilenos , Mentol , Taninos , Aceite de Linaza , Polímeros/química
11.
Food Chem ; 395: 133607, 2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-35802978

RESUMEN

A new and novel poly(vinyl benzyl dithiocarbonate-dimethyl amino ethyl methacrylate) block copolymer (Pvb-DMA-Xa) as adsorbent was synthesized for the vortex-assisted dispersive solid phase microextraction (VA-DSPME) of patulin from apple products and dried fruits using Uv-visible spectrophotometer. The characterization of synthesized Pvb-DMA-Xa block copolymer was performed with Fourier Transform Infrared spectroscopy (FTIR-ATR) technique. Analytical characteristics such as pH, sorbent amount, adsorption time, eluent type and its volume, desorption time and adsorption capacity were optimized. Limit of detection (3Sb/m) and limit of quantitation (10Sb/m) were found 0.3 and 1.0 ng mL-1. Linear dynamic range (LDR), relative standard deviation (RSD) and recovery values were found in the range of 1-30 ng mL-1, 2.1-2.7 % and 93.5-97.3 %, respectively. Enhancement factor (EF) was found 193. The accuracy of the method was confirmed with standard addition method and analyzing of samples by reference method.


Asunto(s)
Malus , Patulina , Frutas/química , Límite de Detección , Malus/química , Metacrilatos , Patulina/análisis , Polímeros/química , Microextracción en Fase Sólida/métodos
12.
Food Chem ; 393: 133464, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-35751221

RESUMEN

A newly synthesized xanthate functionalized chlorinated polypropylene (PP-Xa) was used as adsorbent for the orbital shaker based on dispersive solid phase microextraction (OS-DSPME) of caffein from several tea, coffee, energy drink, coca-cola and chocolate samples using UV-vis. spectrophotometer. Synthesized PP-Xa was characterized using Fourier Transform Infrared spectroscopy (FTIR-ATR) and nuclear magnetic resonance spectroscopy (1H NMR). Various parameters like pH, PP-Xa amount, extraction time, type of eluent and its volume were optimized. Linear range, detection limit (LOD), limit of quantification (LOQ), relative standard deviation (RSD), recovery values, and enrichment factor (EF) were found 90-1000 µgL-1, 27.3 µg L-1, 90 µg L-1, 1.9-2.6%, 98 ± 2%, and 167, respectively. Adsorption capacity of PP-Xa was found 271.9 mg g-1. Standard addition and reference method were used for confirm the accuracy of present method.


Asunto(s)
Cafeína , Microextracción en Fase Sólida , Bebidas/análisis , Límite de Detección , Polipropilenos , Extracción en Fase Sólida/métodos , Microextracción en Fase Sólida/métodos
13.
J Biomater Appl ; 36(9): 1599-1616, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35043697

RESUMEN

Breast cancer is a malignant tumor, which has derived from cells of the breast. Further, a relatively rapid metastasis, and resistance development against all the conventional drug combinations are major clinical issues in breast cancer patients as well as limitations like toxicity, genetic mutation, and metastasis make difficult the use of conventional therapy methods such as chemotherapy, radiotherapy, and local surgery. Therefore, considering the urgent needs, and high death rate in breast cancer cases, the development of new diagnosis and treatment regimens which diagnosed at the early stage and protected normal tissues required for clinical applications. Recently, the combination of tumor diagnosis and treatment within a single platform is a novel perspective, and magnetic nanoparticles are potential candidate owing to their low toxic effect, biocompatibility, biological degradability, superior magnetic properties, and targeting ability to overcome the problems of conventional diagnosis and therapy techniques. Considering these restrictions and requirements, the goal of this research was to investigate the potential of an innovative theranostic agent, which is soybean oil-based polystyrene (PS)-g-soybean oil graft copolymer containing AgNPs (PS-Agsbox) for treatment and MRI-based diagnosis of cancer. Herein, we designed targeted magnetic PS-Agsbox nanoparticles carrying thymoquinone (TQ) that is known for its anticancer potential against breast cancer, and herceptin (HER), which is to bind to the HER2 receptor protein on the surface of HER2-positive tumor cells, and acts by blocking the effects of it. We have successfully demonstrated selective binding, effective uptake of HER-conjugated magnetic PS-Agsbox nanoparticles into MDA-MB-231 (human breast carcinoma cells, a HER2-underexpressing cell line) and SKBR-3 (human breast cancer cells, a HER2-overexpressing breast cancer cell line) cell lines while no effect against L929 (mouse fibroblast cell line). Moreover, the magnetic resonance (MRI) properties of HER-conjugated magnetic PS-Agsbox nanoparticles were also confirmed.


Asunto(s)
Neoplasias de la Mama , Nanopartículas , Animales , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Femenino , Humanos , Ratones , Nanopartículas/química , Nanopartículas/uso terapéutico , Poliestirenos/uso terapéutico , Medicina de Precisión , Aceite de Soja , Trastuzumab/uso terapéutico
14.
Food Chem ; 369: 130973, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34507087

RESUMEN

Polystyrene-polyricinoleic acid copolymer containing silver nano particles (AgPSrici) was synthesized and used in separation of molybdenum from different aqueous and foodstuff samples during a dispersive-µ-solid phase extraction approach. The synthesized nano particles were verified using Fourier transform infraredspectroscopy. An electrothermal atomic absorption spectrometry has been used for measurement of the studied ions. AgPSrici amount pH, sample volume, elution solvent kind, and the time of extraction were the effective parameters that were optimized by one-variable-at-one-time method. Analytical data of the method was calculated and limit of detection, relative standard deviation, limit of quantification were 0.022 µg L-1, 2.9%, 150, and 0.066 µg L-1, respectively. The synthesized adsorption capacity was obtained 170 mg g-1.Accuracy of the method was studied by performing the method on certified reference materials and the presence of different interfering ions was studied. Molybdenum content of different water and foodstuffs was determined by the introduced method.


Asunto(s)
Microextracción en Fase Sólida , Agua , Límite de Detección , Molibdeno , Poliestirenos , Plata , Extracción en Fase Sólida , Espectrofotometría Atómica
15.
Int J Mol Sci ; 22(13)2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-34281198

RESUMEN

Reconstruction of nerve defects is a clinical challenge. Autologous nerve grafts as the gold standard treatment may result in an incomplete restoration of extremity function. Biosynthetic nerve conduits are studied widely, but still have limitations. Here, we reconstructed a 10 mm sciatic nerve defect in healthy rats and analyzed nerve regeneration in poly (ε-caprolactone) (PCL) conduits longitudinally divided by gold (Au) and gold-cobalt oxide (AuCoO) nanoparticles embedded in poly-propylene poly-ethylene glycol (PPEG) membranes (AuPPEG or AuCoOPPEG) and compared it with unmodified PPEG-membrane and hollow PCL conduits. After 21 days, we detected significantly better axonal outgrowth, together with higher numbers of activated Schwann cells (ATF3-labelled) and higher HSP27 expression, in reconstructed sciatic nerve and in corresponding dorsal root ganglia (DRG) in the AuPPEG and AuCoOPPEG groups; whereas the number of apoptotic Schwann cells (cleaved caspase 3-labelled) was significantly lower. Furthermore, numbers of activated and apoptotic Schwann cells in the regenerative matrix correlated with axonal outgrowth, whereas HSP27 expression in the regenerative matrix and in DRGs did not show any correlation with axonal outgrowth. We conclude that gold and cobalt-oxide nanoparticle modified membranes in conduits improve axonal outgrowth and increase the regenerative performance of conduits after nerve reconstruction.


Asunto(s)
Oro/administración & dosificación , Nanopartículas del Metal/administración & dosificación , Regeneración Nerviosa/efectos de los fármacos , Nervio Ciático/efectos de los fármacos , Animales , Cobalto/farmacología , Femenino , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/metabolismo , Oro/farmacología , Nanopartículas del Metal/química , Regeneración Nerviosa/fisiología , Óxidos/farmacología , Poliésteres/química , Poliésteres/farmacología , Polietilenglicoles/química , Polietilenglicoles/farmacología , Polipropilenos/química , Polipropilenos/farmacología , Prótesis e Implantes , Ratas , Ratas Wistar , Células de Schwann/efectos de los fármacos , Células de Schwann/metabolismo , Nervio Ciático/metabolismo
16.
Food Chem ; 359: 129923, 2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-33964654

RESUMEN

A green and efficient analytical approach was reported for simultaneous preconcentration, and separation of Pb(II) and Cd(II) in water, vegetables, and barbecue samples by dispersive solid-phase microextraction prior to their determination using flame atomic absorption spectrometry. A new poly-3-hydroxy butyrate-polyvinyl triethyl ammonium chloride comb-type amphiphilic cationic block copolymer (PHBvbNCl) was synthesized and characterized. Main variables such as pH, sorbent amount, adsorption time, eluent type, desorption time, and sample volume were optimized. Detection limits and working ranges for Pb(II) and Cd(II) were 0.03 µg L-1, 0.15 µg L-1, 0.1-250 µg L-1 and 0.5-375 µg L-1, respectively. Enhancement factor for Pb (II) and Cd (II) were 114 and 98. The adsorption capacity of PHBvbNCl for Pb(II) and Cd(II) was 175.2 mg g-1 and 152.9 mg g-1. After the accuracy of the method was confirmed by the analysis of certified reference materials, it was successfully applied to real samples. Finally, the analytical performance of the present method was compared with other methods.


Asunto(s)
Cadmio/análisis , Plomo/análisis , Adsorción , Extracción en Fase Sólida , Espectrofotometría Atómica , Agua/química
17.
Sci Rep ; 11(1): 5481, 2021 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-33750835

RESUMEN

We synthesized the poly(methyl methacrylate-co-2-aminoethyl methacrylate (PMaema) amphiphilic copolymer in a form of solid phase adsorbent. Then it was used for separation, preconcentration and determination of trace amount of As(III) ions from foods and waters with hydride generation atomic absorption spectrometry. The PMaema was characterized by fourier transform infrared spectrometer and nuclear magnetic resonance spectrometer. The adsorption of As(III) to the PMaema was also supported using computational chemistry studies. The experimental parameters (pH, PMaema amount, adsorption time and ethanol volume) were optimized using a three-level Box-Behnken design with four experimental factors. We observed linear calibration curve for the PMaema amount in the 10-500 ng L-1 range (R2 = 0.9956). Limit of detection, preconcentration factor and sorbent capacity of PMaema were equal to 3.3 ng L-1, 100 and 75.8 mg g-1, respectively. The average recoveries (spiked at 50 ng L-1) changes in the range of 91.5-98.6% with acceptable relative standard deviation less than 4.3%. After validation studies, the method was successfully applied for separation, preconcentration and determination of trace amount of As(III) from foods and waters.

18.
J Biomater Appl ; 36(3): 385-405, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33530824

RESUMEN

Nosocominal infections associated with biofilm formation on urinary catheters cause serious complications. The aim of this study was to investigate the feasibility of the polyurethane (PU) catheter modified with tetracycline hydrochloride (TCH) attached Ag nanoparticles embedded PolyRicinoleic acid-Polystyrene Nanoparticles (PU-TCH-AgNPs-PRici-PS NPs) and the influence on antimicrobial and antibiofilm activity of urinary catheters infected by Escherichia coli and Staphylococcus aureus. For this purpose, AgNPs embedded PRici graft PS graft copolymers (AgNPs-PRici-g-PS) were synthesized via free radical polymerization and characterized by FTIR, HNMR and DSC. AgNPs-PRici-PS NPs were prepared and optimized by the different parameters and the optimized size of nanoparticle was found as about 150 ± 1 nm. The characterization of the nanoparticles and the morphological evaluation were carried out by FTIR and SEM. Short term stability of nanoparticles was realised at 4°C for 30 days. In vitro release profiles of TCH and Ag NPs were also investigated. The formation of biofilm on PU modified TCH-Ag NPs-PRici-PS NPs, was evaluated and the biocompatibility test of the nanoparticles was realized via the mouse fibroblast (L929) and mouse urinary bladder cells (G/G An1). This is the first time that TCH-AgNPs-PRici-PS NPs used in the modification of PU catheter demonstrated high antimicrobial and antibiofilm activities against the urinary tract infection.


Asunto(s)
Antibacterianos/administración & dosificación , Infecciones Relacionadas con Catéteres/prevención & control , Poliestirenos/química , Ácidos Ricinoleicos/química , Plata/administración & dosificación , Infecciones Urinarias/prevención & control , Animales , Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Catéteres/efectos adversos , Catéteres/microbiología , Línea Celular , Portadores de Fármacos/química , Escherichia coli/efectos de los fármacos , Escherichia coli/fisiología , Ratones , Nanopartículas/química , Plata/farmacología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/fisiología
19.
Food Chem ; 344: 128644, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33246682

RESUMEN

This work focuses on the synthesis of novel tannin-functionalized polypropylene copolymers that are designed to inhibit the oxidation of vegetable oils for potential use as packaging materials. An empty glass Petri dish (control), a chlorinated polypropylene-coated glass Petri dish (control) and a series of the tannin-functionalized polypropylene coated glass Petri dishes overlaid with linseed oil were exposed to air and additional white light. Oligomerization of the oxidized linseed oil was assessed by measuring the flow properties of the exposed oil using a viscometer. The antioxidant effect of the tannic acid grafted polypropylene copolymers (PP-Tann) retarded oligomerization of the linseed oil. The molar mass of the linoleic acid overlaid onto the PP-Tann films was the lowest among the tested samples after each time period indicating that tannin-grafted polypropylene may be a promising packaging material for vegetable oils.


Asunto(s)
Antioxidantes/química , Embalaje de Alimentos , Polipropilenos/química , Polipropilenos/síntesis química , Taninos/química , Técnicas de Química Sintética , Oxidación-Reducción , Aceites de Plantas
20.
Food Chem ; 333: 127504, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-32679416

RESUMEN

The aim of this study is to extract zinc and manganese from foods and vegetables using an amphiphilic copolymer adsorbent, poly(styrene)-co-2-vinylpyridine which was synthesized via reversible addition fragmentation chain transfer (RAFT) polymerization from styrene and 2-vinyl pyridine in the presence of a trithiocarbonate and 2,2'-azo-bis isobutyro nitrile (AIBN) in toluene solution under argon at 80 °C. Fourier Transform Infrared (FTIR) and proton nuclear magnetic resonance (1H NMR) spectroscopy were used in the characterization of the obtained copolymer. Under the optimum conditions, several validation variables such as uncertainty measurement, selectivity, robustness, precisions, matrix effects and accuracy were investigated. Taking an adsorption time of 15 min, detection limits of 0.04 µg L -1 and 0.2 µg L-1and 7.9 µg L-1and enrichment factors of 145 and 110 were obtained for Mn(II) and Zn(II), respectively.The method was successfully applied to the analysis of Mn(II) and Zn(II) in foods and vegetables.


Asunto(s)
Manganeso/aislamiento & purificación , Poliestirenos/química , Polivinilos/química , Extracción en Fase Sólida/métodos , Verduras/química , Zinc/aislamiento & purificación , Adsorción , Espectroscopía de Resonancia Magnética , Manganeso/análisis , Polimerizacion , Extracción en Fase Sólida/instrumentación , Espectroscopía Infrarroja por Transformada de Fourier , Zinc/análisis
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