Journal of Polymers and the Environment最新文献

Dye pollution in wastewater is a persistent environmental challenge, with synthetic dyes posing significant threats to aquatic ecosystems and human health. This review article examines the potential of cellulose-based aerogels as a sustainable solution for removing dyes from wastewater. Cellulose aerogels, owing to their high porosity, large surface area, and tailorable surface chemistry, have emerged as promising adsorbent materials for dye remediation. The review outlines the sources and classification of dyes, highlighting their environmental and health implications. It then provides a comprehensive overview of various dye removal methodologies, critically analyzing their advantages and limitations and underscoring the need for effective and sustainable treatment technologies. The preparation of cellulose aerogels, including natural, regenerated, and cellulose derivative variants, is discussed, along with surface modification strategies to enhance their dye adsorption capabilities. Detailed characterization techniques and the assessment of dye removal performance are also covered. The review concludes by synthesizing the key findings and outlining recommendations for future research, such as developing innovative cellulose aerogel formulations, conducting life-cycle assessments, and fostering collaborative efforts to accelerate the adoption of these technologies in wastewater treatment applications. This review aims to contribute to the advancement of sustainable and efficient dye removal solutions using cellulose-based aerogels.

A novel pH sensitive antibiotic carrier hydrogel was synthesized having sustained drug releasing capabilities. The in-situ polymerization of Graphene oxide (GO), Polyvinyl pyrrolidone (PVP), and Carboxymethyl cellulose (CMC) of varying stoichiometry having Ca²⁺ as a linker yielded ternary nanocomposite hydrogels GO/PVP/CMC-II and GO/PVP/CMC-III. The physicochemical, structural, morphological and swelling properties of the binary nanocomposite GO/PVP and ternary nanocomposite hydrogels, GO/PVP/CMC were investigated using FTIR, XRD, SEM, TEM, TGA and DTA. FTIR and XRD confirm successive formation of ternary hydrogels. The hydrogels swelling studies at various pH levels viz. 4.5, 7 and 9.2, show that the swelling ability can be proportionally correlated with CMC concentration. To ensure the efficacy of this innovative hydrogel drug release application, an in vitro Ampicillin loading and release efficiency experiment at pH 7.2 (close to blood pH 7.3–7.5) was performed. Ternary hydrogels GO/PVP/CMC-II and GO/PVP/CMC-III exhibited sustained drug loading and release kinetics (72 h).

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The combination of natural and synthetic polymers for nanomedicine development had many advantages, including less toxicity, biocompatibility, prolonged circulation, higher stability, and ease of surface modification. Here, a novel folic acid-conjugated Camptothecin-loaded-poly (lactic-co-glycolic) acid-glutenin nanoparticles (FA-CPT-PLGA-Glu NPs) was fabricated to treat breast cancer. FA-CPT-PLGA-Glu NPs target breast cancer cells via upregulated folate receptors and delivered their toxic payloads without disrupting healthy cells. First, CPT-loaded PLGA NPs were created using a modified emulsification/evaporation technique. Second, Glu-based CPT-PLGA NPs were synthesized using a layer-by-layer assembly, and their physiochemical properties were validated. CPT encapsulation efficiency and loading capacity into PLGA-Glu NPs were 74.95 ± 1.34% and 4.78 ± 1.08%, respectively. CPT-PLGA-Glu NPs exhibited sustained and controlled release of loaded-CPT from NPs, and the highest content was released in an acidic environment (pH 5.3), which will be advantageous for cancer treatment. Later, FA-CPT-PLGA-Glu NPs were synthesized by simple conjugation chemistry. The fabricated FA-CPT-PLGA-Glu NPs were around 100 nm in size, with a spherical form and crystalline nature. FA-CPT-PLGA-Glu NPs show strong cytotoxicity activity, and its IC₅₀ value was 16.33 µg × mL^− 1 against breast cancer cell line (MCF-7). This folate-receptor-targeted NPs are more effectively internalized into MCF-7 cells, causing ROS generation, cell growth inhibition, and apoptosis. The activity of caspase-3 and − 9 causes MCF-7 cells apoptosis by internalized CPT. Further, internalized CPT induces potential loss of mitochondrial transmembrane and damages the nuclear integrity of the cancer cells. These results showed that the FA-CPT-PLGA-Glu NPs target upregulated folate receptors on the surface of MCF-7 cells.

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A new biomass-based carboxymethyl inulin modified chitosan material was designed and synthesized as an adsorbent for the Cu (II) removal from aqueous solutions, in which carboxymethyl inulin (CMI) with specific degree of substitution (DS) was prepared by optimal three steps alkalization-etherification processes, and then moderately crosslinked with chitosan by DMTMM. The structure and morphology of CMI-CS were characterized using fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), brunauer–emmett–teller (BET) and thermogravimetric analysis (TGA) analyses. The effects of CMI dosage, adsorption time, adsorption temperature, pH and initial Cu (II) concentration on the adsorption capability of CMI-CS to Cu (II) were investigated. The adsorption capacity of the adsorbent for Cu (II) was 49.4 mg/g under the conditions of CMI and CS mass ratio 3:2, pH 6, and adsorption time for 90 min. Its adsorption kinetics fitted the pseudo-second-order model, and adsorption isotherms followed by the Freundlich and the Temkin models well. XPS, FTIR, and SEM were used to explore the adsorption mechanism. The results demonstrated chemisorption and physisorption coexist in the adsorption process. The nitrogen-containing groups and oxygen-containing functional groups of CMI-CS adsorbent participated in the adsorption of Cu (II) through electrostatic interaction and chelation. Based on the above traits, the biomass-based adsorbent shows promising application in wastewater treatment.

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Attempts were made to produce osteoinductive three- dimensional (3D) porous scaffolds with interconnected pores. Among the synthetic polymers, poly (ε- caprolactone) (PCL) was proven to be highly biocompatible and osteoinductive. However, it suffers from shrinkage due to high crystallinity and fast crystal growth. Here, we used polylactic acid, which is a rigid, low- crystalline and biocompatible polymer, as the major phase blended with PCL comprising the minor phase. However, these two polymers are highly incompatible and the PCL minor phase tend to form large droplets, distributing it unevenly throughout the continuous phase. Here, we used cellulose nanocrystals (CNCs), as a hydrophilic and osteoinductive nanoparticle, to suppress coalescence of PCL droplets and a tri-block copolymer of PCL-PEG-PCL (BCP) to reduce the interfacial tension of the two phases. 3D foams were prepared using thermally-induced phase separation and salt leaching and the porosity and pore size was tuned using CNC and BCP. The biocompatibility of the 3D scaffolds was evaluated by MG63 cell lines and the results indicated high biocompatibility. The scaffolds were also quite successful at inducing the osteogenesis of hMSCs. The specimen containing 10% BCP and 1.0% CNC had the highest calcium deposition with the highest expression of bone- specific genes.

The discharge of industrial wastewater containing Cr(VI) can severely damage the surrounding environment and cause serious threats to human health. Exploring high-performance adsorbents to rapidly remove Cr(VI) could be a popular idea for solving this problem. Herein, a composite (Fe₃O₄@CS-APTMS) was fabricated by using Fe₃O₄ as the core coated with chitosan and then functionalized with APTMS for simultaneous Cr(VI) reduction and adsorption. Although the APTMS grafting and the cross-linking reaction covered the Fe₃O₄@CS-APTMS surface with more obvious folding and wrinkling and blocked the interior pores, the graft-rich amino functional groups could effectively enhance the acidic pH adaptability and the performance of Fe₃O₄@CS-APTMS to achieve an adsorption capacity of 269.54 mg g⁻¹ at 298 K and pH 2.0. The primary reaction mechanism involving electrostatic attraction, reduction, and chelation of Cr(VI) has been thoroughly investigated through FTIR, XPS, and DFT analyses. Moreover, the concentration of Cr(VI) (32 mg L⁻¹) in artificial electroplating wastewater substantially decreased to 0.09 mg L⁻¹ post-treatment, significantly below China’s discharge standard (0.2 mg L⁻¹). Furthermore, the composite demonstrated excellent resistance to disturbances and recyclability. Thus, the synthesized composite emerges as a promising alternative material for efficiently treating chromium-containing electroplating wastewater, underscoring the importance of amino-modified materials in Cr(VI) reduction and detoxification in aquatic environments.

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Poly (butylene adipate-co-terephthalate) (PBAT) foam is a green and promising candidate to replace traditional oil-based polymer foam in the fields of buffer packaging, sporting goods and biomedicine, because of its admirable toughness, good resilience properties and excellent biodegradability. Herein, a novel methodology using the combination of autoclave foaming and vacuum foaming was reported to prepare chain-extended PBAT (CPBAT)/graphene nanosheets (GNPs) microcellular foams with high volume expansion ratio (VER). Compared with that prepared by single autoclave foaming, PBAT microcellular foams prepared by the combination of autoclave foaming and vacuum foaming possessed a higher VER up to 7.60, which had an increase of 324.58%. GNPs were used for the achievement of the filling modification of PBAT, which increased the cell density and compression properties of PBAT foams. When GNPs content were 2 phr, the compressive strength of CPBAT/GNPs2 foam reached 0.82 MPa. Above all, this research will provide a new facile approach to prepare biodegradable microcellular polymer foams with high VER.

Glioblastoma multiforme is one of the most vascularized and invasive solid tumors because it constantly needs to be vascularized due to the production of angiogenic factors, including vascular endothelial growth factor and epidermal growth factor. As a result, scientists are searching for complementary, alternative, or even combination medicines with fewer adverse effects and high efficacy. One type of statin that is effective in treating some forms of cardiovascular disease is Atorvastatin, which is also recognized as a suitable therapeutic option for inhibiting the growth of angiogenesis and coronary vessel pathogenesis. In the current research, we synthesized and characterized magnetic Fe₃O₄–chitosan nanoparticles loaded with Atorvastatin (ch/Fe/ATV), and we evaluated their anti-tumor efficiency in-vivo as well as their anti-proliferative, apoptotic, and the cell cycle arrest effects on the C6 glioma cell line in-vitro. In C6 cells, it was discovered that ch/Fe/ATV was useful in inducing ROS, apoptosis-induced cell death, and suppression of proliferation. During the in-vivo stage of the study, it was shown that ch/Fe/ATV could effectively reduce tumor development and improve the survival rate of animal models of GBM. qRT-PCR findings in this study demonstrate that ch/Fe/ATV may down-regulate anti-apoptotic factors including Bcl-2, VEGF, and BDNF, which are critical factors in tumor growth, and up-regulate apoptotic factors such as BAX, Caspase 3, and p53. Additionally, we discovered that applying a magnet to the tumor site helped increase the amount of ATV doses delivered to the tumor using ch/Fe/ATV nanoparticles.

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After the application of Zn–SA–chitosan bionanoconjugates (BNCs), the physio-biochemical responses of two wheat varieties WH-1124 (heat resistant) and WH-542 (heat sensitive) under terminal heat stress(THS) were assessed in the current study. Zn (Zinc) and SA (Salicylic acid) were slowly released by BNCs to maintain nutrient availability for plants.Application of BNCs enhanced wheat production by enhancing seedling emergence, seed vigour index, and cellular redox homeostasis through antioxidant status regulation, enhanced photosynthetic rate, and cellular and osmotic stability which are essential for stress resistance and plant growth. BNCs (0.01–0.16% w/v) administration at booting and anthesis stages fabricated cellular homeostasis by reducing oxidative damage by suppressing malondialdehyde (MDA), and hydrogen peroxide (H₂O₂) restoring proline, and its metabolizing enzymes in flag leaf. Comparing control plants treated with, BNCs (0.08%) considerably slowed the loss of carotenoid and chlorophyll levels in both wheat cultivars. Furthermore, foliar treatment of BNCs boosted the activities of superoxide dismutase, catalase, peroxidase, ascorbate peroxidase, glutathione reductase, and glutathione peroxidase in both flag leaf and developing grains on exposure of late sown wheat to THS. BNCs (0.08%) not only promoted early maturity but also significantly slowed the plant height reduction from 12.6% in the control group to just 8.7%. Similarly, the reduction in spike length with awns, and grain yield per pot was controlled to just 5.5% from 7.9% in control.Early emergence, vigorous germination, and early flowering by BNCs synergistically helped the wheat plant in mitigating THS and giving better productivity by providing enough time for grain filling.

Poly(hydroxyalkanoates) (PHAs) are emerging as sustainable materials in packaging and medical device industries. Nevertheless, the high cost and the need to improve the mechanical properties have limited their widespread use. Blending with other bio-based polymers, such as poly(lactic acid) (PLA), has been proposed in previous studies. This study investigates the effects of temperature, azodicarbonamide (AZ, foaming agent), boron nitride (BN, filler), and multilayer film/foam coextrusion on the properties of a blend containing an amorphous PHA and PLA. The effect of twin-screw micro-compounder temperature (185 °C & 205 °C) and BN concentrations of 1, 2, 3, 5, and 10 wt% (185 °C) on the properties of the PHA/PLA blend were investigated using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and tensile testing. Design of experiments (DoE) was used to find the optimal concentrations of AZ and BN (205 °C) using JMP® software. The response surface analysis predicted an optimal design based on the target response levels (modulus, tensile strength, strain at break, and toughness). This formulation was prepared and characterized using DSC, TGA, tensile, and melt flow index (MFI) measurements. Finally, this formulation was processed via film/foam coextrusion and examined using scanning electron microscopy (SEM) and density measurements. This study demonstrated that AZ and BN can be used to manipulate the mechanical properties and crystallinity of PHA/PLA blends, while reducing the overall material cost via density reduction (20–21% for the optimal formulation). Furthermore, reducing the concentration of AZ using the I-optimal design in this study could alleviate the toxicity concerns for food packaging.