In this work, gelatin (G)-polyacrylamide (PAAm)-based interpenetrating polymer network (IPN) hydrogels involving maleic acid (MA) was prepared using by radical polymerization. Full-IPN and semi-IPN ...hydrogels were synthesized by using glutaraldehyde and ethylene glycol dimethacrylate (EGDMA) as a crosslinker. The water absorbency of hydrogels was investigated, and the values increased with MA and G. The chemical structures of full-IPN and semi-IPN hydrogels were tested by Fourier Transform Infrared Spectroscopy (FTIR). Morphological test was done by using Scanning Electron Microscope/ Energy Dispersive X-ray Spectroscopy (SEM/EDX). Thermal properties were examined with Differential scanning calorimeter (DSC) analyzer and Thermogravimetric analysis (TGA). The mechanical analysis was performed with Zwick Universal Testing Machine. Thermal and mechanical stabilities of full-IPN hydrogel was higher than semi-IPN. The efficiency of adsorption parameters (contact time, initial feed concentration, and pH) on Chromium (VI) ion adsorbing property of Full-IPN hydrogel was also determined. Isotherms were explained with the Langmuir or Freundlich equations. According to the results of both isotherms, it can be said that the hydrogel surface was homogeneous, and the adsorption of Chromium (VI) occurred in a monolayer.
Bu çalışmada, jelatin (G) -poliakrilamid (PAAm) bazlı, maleik asit (MA) içeren iç içe geçen polimer ağı (IPN) hidrojelleri, radikal polimerizasyon kullanılarak hazırlanmıştır. Tam-IPN ve yarı-IPN hidrojeller, çapraz bağlayıcı olarak glutaraldehit ve etilen glikol dimetakrilat (EGDMA) kullanılarak sentezlendi. Hidrojellerin su emiciliği incelendi ve değerler MA ve G ile arttı. Tam IPN ve yarı IPN hidrojellerin kimyasal yapıları Fourier Dönüşümü Kızılötesi Spektroskopisi (FTIR) ile test edildi. Taramalı Elektron Mikroskobu/ Enerji Dağılımlı X-ışını Spektroskopisi (SEM/EDX) kullanılarak morfolojik test yapıldı. Termal özellikler Diferansiyel taramalı kalorimetre (DSC) analizörü ve Termogravimetrik analiz (TGA) ile incelenmiştir. Mekanik analiz, Zwick Universal Test Makinesi ile yapıldı. Tam IPN hidrojelin termal ve mekanik stabiliteleri yarı IPN'den daha yüksekti. Tam-IPN hidrojelinin Krom (VI) iyonu adsorbe etme özelliği üzerindeki adsorpsiyon parametrelerinin (temas süresi, başlangıç besleme konsantrasyonu ve pH) etkinliği de belirlendi. İzotermler Langmuir veya Freundlich denklemleriyle açıklandı. Her iki izotermin sonucuna göre, hidrojel yüzeyinin homojen olduğu ve Krom (VI) adsorpsiyonunun bir tek tabakada meydana geldiği söylenebilir.
Green synthesis of silver nanoparticles was carried out using leaf extract from Calluna vulgaris. The formation of nanoparticles was confirmed through the emergence of a surface plasmon resonance ...band in ultraviolet-visible spectroscopy. The characterization conducted using various microscopic techniques revealed that the nanoparticles mostly ranged in size from approximately 20 to 70 nm. Analysis, including Fourier transform infrared spectrometry, X-ray diffraction, and energy-dispersive X-ray spectroscopy, confirmed the chemical, crystalline structure, and presence of silver, respectively. The synthesized nanoparticles exhibited notable stability with an average zeta potential of -23.1 ± 0.6 mV. Evaluation of their antibacterial activity against Staphylococcus aureus and Escherichia coli demonstrated significant efficacy with diameters of inhibition zones measuring 10.23 ± 0.54 mm and 15.38 ± 0.32 mm, respectively. Additionally, the nanoparticles displayed a remarkable inhibition of approximately 88% against E. coli biofilm formation at a concentration of 100 μg/mL. They also exhibited unique photocatalytic performances. This research contributes to the literature in this field by producing new silver nanoparticles with cost-effectiveness, stability, antibacterial, antioxidant, antibiofilm, and photocatalytic properties, while using a previously untapped plant extract for this purpose.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
pH-Sensitive alginate (ALG)/sodium carboxymethylcellulose (CMC) hydrogels were synthesized using a novel technique to utilize as a drug carrier in this study. The characterization of hydrogels was ...performed using FTIR (Fourier-transformed infrared spectroscopy), SEM(scanning electron microscopy), TGA (thermogravimetric analysis), DSC (differential scanning calorimetry), gel content and mechanical tests. The last technique is new and it is compared with the most well-known ionic crosslinking method to investigate the effectiveness of the technique. Gel content, degradation and thermal and mechanical stabilities were found to be higher. Swelling and degradation behaviors of hydrogels were studied in simulating gastric juice of pH 1.2 or simulating intestinal fluid of pH 6.8 and simulating colon fluid of pH 7.4 at 37 °C. The maximum swelling degree was observed at pH 7.4, and the minimum swelling degree was obtained at pH 1.2. An Anti-arrhythmics drug, propranolol hydrochloride (PPN), was loaded onto the obtained hydrogels as a model drug. Encapsulation efficiency (%) and drug loading amount (g/g) of ALG/CMC hydrogels synthesized by a new technique were found to be 61–68.4% and 0.152–0.171 g/g, respectively. The values of initial burst release at 15 min (%), drug released at 7 h (%) and equilibrium drug release were researched. Different kinetic model parameters (zero-order, first-order, Higuchi, and Korsmeyer–Peppas models) were calculated to investigate the drug release mechanism. The engineered hydrogels displayed controlled swelling capacity, cavitary surfaces, more porosity, high degradation resistance, gel content, thermal and mechanical properties and controlled drug release. These findings suggest that hydrogels synthesized by this new technique may be useful as a drug delivery system.
Graphical abstract
Abstract
In this study, a series of semi-interpenetrating polymer network (IPN) hydrogels were prepared as a support material for lipase immobilization. Hydrogels were synthesized via free radical ...polymerization in different compositions of chitosan (Cs), acrylamide (AAm), and citraconic acid (CA). The swelling values of the hydrogels were found to be 240-400%. Depending on the swelling results, Cs-P(AAm-co-CA)-2 hydrogel was chosen for lipase immobilization. Three different types of immobilization technique were carried out. Lipase release behaviors were investigated, and immobilization yields of three immobilization methods were compared, and the maximum immobilization yield value was determined for entrapment method.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Sodium carboxymethyl cellulose (NaCMC) and carrageenan (CG) hydrogels were synthesized for potential use in the growth of wheatgrass plant. The water absorbency and gel content properties of prepared ...hydrogels were investigated. Water absorbency was reduced with increasing the amounts of polymer and crosslinker, in contrast with gel content results. The treatment of hydrogels with soil enhanced the water retention capacity of soil. Zinc micronutrient was loaded in both hydrogels by classic entrapment method. The zinc release behavior of hydrogels in water and soil were determined and the release rate decreased with high gel content and crosslinking density. The influence of zinc-loaded hydrogel on the wheatgrass plant performance were also investigated by using pot experiments. The growth of the wheatgrass
(Triticum aestivum)
was obviously increased by the use of zinc-loaded hydrogels. The increase in plant performance by using these hydrogels suggests that prepared hydrogels can be used as a controlled fertilizer system in agriculture fields.
Black cumin seed pulp (C), as well as biochar (CC) produced via pyrolysis of black cumin seed pulp were used to remove methylene violet 2B (MV) and basic yellow 28 (BY28) from aqueous solution. ...Adsorption isotherms and kinetics were applied at 10, 25, and 35 °C. The adsorption of methylene violet 2B and basic yellow 28 on the black cumin seed pulp and biochar surface was exothermic; the heat of adsorption values were lower than 0. The adsorption capacities of BY28-C, BY28-CC, MV-C, and MV-CC were 212.8, 625, 164, and 909 mg g-1 at 25 °C, respectively. The adsorption of black cumin seed pulp and biochar data were examined with the Freundlich, Langmuir, Temkin, Dubinin-Radushkevich (D-R), and Flory-Huggins (F-H) isotherm models. The kinetics of the adsorption were fitted to the pseudo first-order and pseudo second order equations. The pseudo second order equation gave a better fit than the pseudo first-order equation.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
A series of nanoporous sodium carboxymethyl cellulose (NaCMC) hydrogel beads were prepared using FeCl3 ionic crosslinker by changing polymer and crosslinker percentages (%). Characteristics of the ...hydrogels were investigated by gel content, swelling test, degradation test, Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR), Scanning Electron Microscope/Energy Dispersive X-ray Analysis (SEM/EDX), and Atomic Force Microscopy (AFM). Swelling experiments were studied by changing time, temperature, and pH. The swelling percentage (S%) regularly decreased with increasing the amounts of polymer and crosslinker, in contrast with gel content results. NaCMC hydrogels were found to be sensitive to pH variations. The degradation test showed that hydrogels had good stability and their degradation period varied from 30 to 36 days. According to SEM analysis, NaCMC hydrogels had mostly nanoporous structure. The average granule and pore sizes of the least swollen NaCMC-12 hydrogel were found to be 13.1±0.3 nm and 82.1±3.2 nm. The elemental compositions of hydrogels were determined with EDX. The minimum average surface roughness (Ra) and root mean square roughness (Rms) parameters were found to be 15.7±1.9 nm and 20.3±2.2 nm for NaCMC-12 hydrogels by AFM. Due to their good morphologies, stabilities, and swelling behaviors, NaCMC hydrogels can be suitable for biomaterial applications.
A series of κ-carrageenan (κ-CG) hydrogels were prepared by using glutaraldehyde (GA) as crosslinker for controlled releasing of copper and manganese micronutrients. The hydrogels were characterized ...by gel content, swelling and degradation tests, Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR) and Scanning Electron Microscope (SEM) observations. The variations of swelling percentages (S%) with time, temperature and pH were determined for all hydrogels. As the amounts of crosslinker increased, S% decreased regularly in contrast to gel content results. The higher swelling values were obtained in basic medium than acidic and neutral mediums for all κ-CG hydrogels. Releasing of copper and manganese micronutrients from κ-CG hydrogels was investigated in water and soil. A simulated releasing model was also applied to estimate the releasing behaviors in agricultural irrigations. In all release studies, the cumulative release values increased with decreasing GA amounts. The release kinetic parameters were also calculated. It was detected that the releasing of micronutrients in soil was slower than that in water.
Green synthesis of silver nanoparticles was carried out using leaf extract from Calluna vulgaris. The formation of nanoparticles was confirmed through the emergence of a surface plasmon resonance ...band in ultraviolet-visible spectroscopy. The characterization conducted using various microscopic techniques revealed that the nanoparticles mostly ranged in size from approximately 20 to 70 nm. Analysis, including Fourier transform infrared spectrometry, X-ray diffraction, and energy-dispersive X-ray spectroscopy, confirmed the chemical, crystalline structure, and presence of silver, respectively. The synthesized nanoparticles exhibited notable stability with an average zeta potential of -23.1 ± 0.6 mV. Evaluation of their antibacterial activity against Staphylococcus aureus and Escherichia coli demonstrated significant efficacy with diameters of inhibition zones measuring 10.23 ± 0.54 mm and 15.38 ± 0.32 mm, respectively. Additionally, the nanoparticles displayed a remarkable inhibition of approximately 88% against E. coli biofilm formation at a concentration of 100 μg/mL. They also exhibited unique photocatalytic performances. This research contributes to the literature in this field by producing new silver nanoparticles with cost-effectiveness, stability, antibacterial, antioxidant, antibiofilm, and photocatalytic properties, while using a previously untapped plant extract for this purpose.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Nanoparticles are used for several commercial applications, especially medical applications, energy-based research, and environmental applications. The usage of nanoparticles is increasing worldwide ...due to their unique properties, so all livings are exposed to these materials deliberately or unknowingly. The toxic nanoparticles disrupt the ecological balance of environment. The accumulation, surface area, particle size or shape of nanoparticles, exposure route, exposure time and dissolution contribute to the toxicity. The production of copper (II) oxide nanoparticles has expanded speedily in the last years so; it is important to know the risks that may be caused by their toxicological risks in ecosystems. This review emphasizes the environmental fate of copper (II) oxide nanoparticles. The environmental fate relates to their shapes, sizes, and physicochemical properties. The updated information on the toxicity of copper (II) oxide nanoparticles to aquatic organisms is given. Copper (II) oxide nanoparticles penetrate directly or indirectly into the organs of aquatic organisms through skin absorption, and/or nutrition. After the exposure, protein denaturation, protein oxidation, DNA damage, oxidative stress, generation of reactive oxygen species, hemolysis, and even cell death occurs in aquatic organisms. This review may assist in interdisciplinary studies to evaluate potential toxicity of copper (II) oxide nanoparticles in aquatic ecosystems.
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