CARBOHYDRATE POLYMERS
·
2021
·
IF 9.381
Tianzhu Shi,Zhengfeng Xie,Zhu Zhu,Wei Shi,Yucheng Liu,Minyao Liu
In the present study, a new potential adsorbent for the separation and removal of heavy metal ions was prepared using hydrazide modification. Characterization of structural and chemical properties of the absorbent indicated the dialdehyde sodium alginate (DSA) grafted adipic acid dihydrazide (AAD) plays a crucial role. The adsorption process correlated well with Freundlich isotherm and pseudo-second-order kinetics models . Additionally, the adsorption capacities for Hg 2+ , Pb 2+ , Cd 2+ , and Cu 2+ were 7.833, 2.036, 4.766, and 3.937 mmol g −1 , respectively. The thermodynamic parameter for the sorption demonstrated the process is endothermic and spontaneous. FT-IR and XPS analysis revealed the combination of chelation interactions and ion exchange between nitrogen, oxygen atoms and heavy metal ions. Moreover, after 10 times adsorption–desorption recycles, the adsorption efficiency of the adsorbent was slightly decreased. In conclusion, the as-prepared adsorbent has great potential in practical water pollution purification .
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials
·
2019
·Vol. 12
·期 18
·2923
·
IF 2.972
You Luo,Haiqing Liu,Shanzhong Yang,Jiarui Zeng,Zhenqiang Wu
The aim of this work was to develop green and bioactive films with sodium alginate incorporating guava leaf extracts. Seven formulations were performed with a different sodium alginate: Guava leaf water extract (WE)/ethanolic extract (EE) proportions (100:0, 90:10, 85:15, 80:20), and glycerol were used as a plasticizer. The HPLC-PDA analysis showed the main phenolic compounds in WE were gallic acid, ellagic acid, quercetin-3-O-β-D-xylopyranoside, avicularin and quercetin. The main polyphenols in EE were rutin, isoquercitrin, quercetin-3-O-β-D-xylopyranoside, avicularin, quercitrin, quercetin and kaempferol. Guava leaf extracts could greatly enhance the antioxidant activity, antibacterial activity, tensile strength and water solubility of the sodium alginate film as well as the water barrier property, while inducing a decrease in the moisture content and elongation at the break. The FTIR and SEM analyses indicated that intermolecular hydrogen bonding between the guava leaf extract and sodium alginate resulted in a more compact structure in the composite films. These results indicated that sodium alginate-guava leaf extract films might be developed into antiradical and antimicrobial food packaging materials.Keywords:bioactive film;sodium alginate;guava leaf extract;polyphenol;antioxidant;antibacterial
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymers
·
2019
·Vol. 11
·期 8
·1239
·
IF 3.164
Yiying Yue,Xianhui Wang,Qinglin Wu,Jingquan Han,Jianchun Jiang
Hydrogels have been widely used in water purification. However, there is not much discussion and comparison about the effects of different nanofillers on the reinforcement and adsorption performances of hydrogels, which can be subjected to rapid water flow and possess strong adsorption ability. In this work, polyacrylamide (PAAM)-sodium alginate (SA) interpenetrating polymer network-structured hydrogels were prepared by in situ polymerization. PAAM formed the first flexible network and SA constructed the second rigid network. Three kinds of inorganic nanoparticles including carbon nanotubes (CNTs), nanoclays (NCs), and nanosilicas (NSs) were incorporated into a PAAM-SA matrix via hydrogen bond. The obtained hydrogels exhibited a macroporous structure with low density (≈1.4 g/cm3) and high water content (≈83%). Compared with neat PAAM-SA, the hydrogels with inorganic nanoparticles possessed excellent mechanical strengths and elasticities, and the compression strength of PAAM-SA-NS reached up to 1.3 MPa at ε = 60% by adding only 0.036 g NS in a 30 g polymer matrix. However, CNT was the best filler to improve the adsorption capacity owing to its multi-walled hollow nanostructure, and the adsorption capacity of PAAM-SA-CNT was 1.28 times higher than that of PAAM-SA. The prepared hydrogels can be potential candidates for use as absorbents to treat wastewater.Keywords:hydrogel;inorganic nanofillers;interpenetrating polymer network;mechanical behavior;adsorption properties
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2019
·
IF 4.784
Hong Zhang,A.M. Omer,Zhaohong Hu,Li-Ye Yang,Chao Ji,Xiao-kun Ouyang
In this work, composite hydrogel beads based on magnetic bentonite/carboxymethyl chitosan/sodium alginate (Mag-Ben/CCS/Alg) were fabricated and their ability to adsorb copper ions in water was studied. The structure and properties of the composite were characterized via SEM, FTIR, XPS, TGA , VSM, and Zeta potential tests. The effects of the adsorbent dosage, adsorption time, pH, temperature, and initial concentration of Cu(II) on the adsorption results were studied. The results showed that Mag-Ben/CCS/Alg reached equilibrium after 90 min of adsorption, the removal rate of Cu(II) was 92.62 ± 0.39%, and the maximum adsorption capacity was 56.79 mg/g (30 °C). The removal rate of Cu(II) by Mag-Ben/CCS/Alg still remained above 80% after recycling four times. The adsorption process of Cu(II) by Mag-Ben/CCS/Alg occurred in accordance with the quasi-second-order kinetic model and Langmuir adsorption isotherm. The adsorption process was spontaneous and endothermic.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CELLULOSE
·
2018
·Vol. 25
·期 6
·3533-3544
·
IF 3.809
Yang Jin,Xia Yunfei,Xu Peng,Chen Beibei
Abstract To overcome the poor mechanical properties of biomass aerogels in oil/water separations, three different freeze-casting methods were used including direct freezing, unidirectional freezing, and bidirectional freezing with sodium alginate (SA) aerogels reinforced with cellulose nanofibrils (CN). After chemical crosslinking and silane modification, compression testing revealed that the SA/CN aerogels with parallel lamellar microstructures prepared by bidirectional freezing exhibited super-elasticity with the minimal energy dissipation of ~ 0.04 in each cycle, a maximum compressive stress of 80.4 kPa, and minimal plastic deformation at ~ 4.15%. Additionally, the water and oil contact angle of the surface of the lamellar SA/CN aerogel was 148.7° and 0°, respectively. By combining the super-elasticity and hydrophobicity/superoleophilicity, the lamella SA/CN aerogels could be reused for the separation of oil/water mixture with oil absorption capacities up to 34 times its weight. Furthermore, the lamellar SA/CN aerogel could continuously separate oil/water mixtures with the assistance of a pump. Therefore, the present study offers a simple and environmentally friendly method for fabrication of super-elastic and hydrophobic/superoleophilic biomass aerogels that are applied to continuous removal of oil from water. Graphical Abstract
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2018
·
IF 13.325
Peng Li,Gong Jinghua,Ma Jinghong
Electro-responsive hydrogels have attracted great attentions because the electric stimuli is easy to be applied and controlled. Thus, it is expected to generate electro-responsive hydrogel fiber to improve electro-response rate. In this paper, graphene oxide/hydrolyzed polyacrylamide/sodium alginate (GO/HPAM/SA) hydrogel fibers were prepared by microfluidic spinning. The structure and morphologies of hydrogel fibers were characterized by FTIR and SEM. The electro-response behaviours were also studied. The results indicate that GO/HPAM/SA hydrogel fibers exhibit bending deformation in an electric field. In Na 2 SO 4 solution, the hydrogel fibers first bend toward the cathode, and then bend toward the anode. It is suggested the bending of the hydrogel fibers is caused by two major factors, one is the osmotic pressure difference, another is the pH gradient induced by electrochemical reactions. Keywords Electro-responsive hydrogel fiber Bending behaviour Osmotic pressure difference pH gradient
✓ 已验证
产品关联
DOI
高影响因子
POLYMER BULLETIN
·
2018
·Vol. 76
·期 1
·87-102
·
IF 1.589
Guo Ting,Zhang Ning,Huang Jinbao,Pei Ying,Wang Fang,Tang Keyong
To improve the durability and bioavailability of alginate, a one-step extrusion method was successfully applied to prepare alginate/gelatin core–shell beads. Gelatin cross-linked with glutaraldehyde was used as the core, while sodium alginate was used as the shell. To evaluate the effect of the sodium alginate shell on the in vitro drug release properties of the beads for biomedical applications, two drug models were used: water-soluble metformin hydrochloride and water-insoluble indomethacin. The structure and properties of different core–shell beads were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy and swelling tests. The results showed that the beads consist of obvious inner core and outer skin layer which coats the surface stably. In addition, the core–shell structure improved the thermal stability of the beads and the entrapment efficiency reached 90% with a sodium alginate shell. As demonstrated, there is a gradual decrease in the swelling degree as the GTA or alginate concentration increases. For indomethacin, the cumulative release was 8.7% after 360 min in HCl buffer. The anomalous transport mechanism was the predominant factor affecting the release behavior of the metformin hydrochloride-loaded beads and indomethacin loaded beads were controlled by case-II transport. This work suggests that the core–shell structure could improve the swelling properties and drug release behavior of the beads.
✓ 已验证
DOI
高影响因子
JOURNAL OF BIOMATERIALS APPLICATIONS
·
2018
·
IF 2.082
Jingwen Wu,Guohou Miao,Zhichao Zheng,Zhengmao Li,Wen Ren,Caijuan Wu,Yuanjing Li,Zhu Huang,Lan Yang,Lvhua Guo
Drug delivery and release are a major challenge fabricating bone tissue engineering. In this study, we fabricated new sustained release hydrogel scaffolds composited of mesoporous bioactive glass, sodium alginate and gelatin by a three-dimensional printing technique. Naringin and calcitonin gene-related peptide were used as drugs to prepare drug-loaded scaffolds by direct printing or surface absorption. The physicochemical properties of the scaffolds and the drug release profiles of the two drug-loading models were investigated. We also examined the biocompatibility of the scaffolds, as well as the effect of the released medium on the proliferation and osteogenic differentiation of human osteoblast-like MG-63 cell. The results showed that the scaffolds had a high porosity (approximately 80%) with an interconnected cubic pore structure, rough surface morphology, bioactivity and strong biocompatibility. Furthermore, the naringin or calcitonin gene-related peptide co-printed into the scaffold displayed a steady sustained release behaviour for up to 21 days without an initial burst release, while both naringin and calcitonin gene-related peptide absorbed onto the surface of the scaffold were completely released within two days. MG-63 cells cultured with the extraction containing released drugs displayed promoted cell proliferation and the expression of osteogenesis-related genes more effectively compared with the drug-free extractions. Therefore, these results demonstrate that the developed mesoporous bioactive glass/sodium alginate/gelatin sustained release scaffolds provide a potential application for bone tissue engineering.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIO-MEDICAL MATERIALS AND ENGINEERING
·
2014
·Vol. 24
·期 1
·633-641
·
IF 0.847
Zhao Peng,Deng Cuijun,Xu Hongzhen,Tang Xing,He Hailong,Lin Chao,Su Jiansheng
Photo-crosslinked chitosan-gelatin scaffolds were fabricated and applied for chondrocyte culture in vitro. Photocurable methacryloyl chitosan was synthesized and characterized by FTIR and 1H NMR, respectively. Microstructure and mechanical properties of the chitosan-gelatin scaffold treated with or without EDC as crosslinking agent were analyzed by scanning electronic microscopy (SEM), compression and viscoelastic measurement. It is demonstrated that EDC-treated chitosan-gelatin scaffold possesses better porous structure and improved mechanical properties. Photo-crosslinked chitosan-gelatin scaffold could be further integrated in sodium alginate hydrogel using calcium chloride to support proliferation of chondrocytes for over 21 days and maintain spherical phenotype, as evaluated by AlamarBlue assay and SEM, respectively, implying that the chitosan-gelatin-hydrogel system exhibits great cyto-biocompatibility. Results of this study show that photo-crosslinked chitosan-gelatin scaffold in sodium alginate hydrogel is suited as a scaffold candidate for cartilage tissue engineering.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ULTRASONICS SONOCHEMISTRY
·
2016
·
IF 4.556
Liping Feng,Yanping Cao,Duoxia Xu,Shaojia Wang,Jie Zhang
In this study, the effects of ultrasound with different ultrasonic frequencies on the properties of sodium alginate (ALG) were investigated, which were characterized by the means of the multi-angle laser light scattering photometer analysis (GPC-MALLS), rheological analysis, circular dichroism (CD) spectrometer and scanning electron microscope (SEM). It showed that the molecular weight (M w ) and molecular number (M n ) of the untreated ALG was 1.927 × 10 5 g/mol and 4.852 × 10 4 g/mol, respectively. The M w of the ultrasound treated ALG was gradually increased from 3.50 × 10 4 g/mol to 7.34 × 10 4 g/mol while the M n of ALG was increased and then decreased with the increase of the ultrasonic frequency. The maximum value of M n was 9.988 × 10 4 g/mol when the ALG was treated by ultrasound at 40 kHz. It indicated that ultrasound could induce ALG degradation and rearrangement. The number of the large molecules and small molecules of ALG was changed by ultrasound. The value of d n /d c suggested that the ultrasound could enhance the stability of ALG. Furthermore, it was found that ALG treated by ultrasound at 50 kHz tended to be closer to a Newtonian behavior, while the untreated and treated ALG solutions exhibited pseudoplastic behaviours. Moreover, CD spectra demonstrated that ultrasound could be used to improve the strength of the gel by changing the ratio of M/G, which showed that the minimum ratio of M/G of ALG treated at 135 kHz was 1.34. The gel-forming capacity of ALG was correlated with the content of G-blocks. It suggested that ALG treated by ultrasound at 135 kHz was stiffer in the process of forming gels. The morphology results indicated that ultrasound treatment of ALG at 135 kHz increased its hydrophobic interaction and interfacial activity. This study is important to explore the effect of ultrasound on ALG in improving the physical properties of ALG as food additives, enzyme and drug carriers.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Mengshuo Du,Yingying Wang,Youyu Cao,Wenzhi Tang,Zhonghong Li
Metal–organic frameworks (MOFs) are attractive adsorbents for heavy metal capture due to their superior stability, easy modification, and adjustable pore size. However, their inherent microporous structure poses challenges in achieving a higher adsorption capacity. Defect engineering is considered a simple method to create hierarchical MOFs with larger pores. Here, we employed l-aspartic acid as a mixed linker to bind Zr4+ clusters in competition with fumaric acid of MOF-801 to create defects, and the pore size was increased from 4.66 to 15.65 nm. Mercaptosuccinic acid was subsequently used as a postexchange ligand to graft the resultant MOF-801 by acid-ammonia condensation to further expand the pore size to 22.73 nm. Notably, the −NH2, −COOH, and −SH groups contributed by these two ligands increased the adsorption sites for Pb(II). The obtained defective MOF-801 with larger pores was thereafter loaded onto sodium alginate to form aerogel beads as adsorbents, and an adsorption capacity of 375.48 mg/g for Pb(II) was achieved, which is ∼51 times that of pristine MOF-801. The aerogel beads also exhibited outstanding reusability with a removal efficiency of ∼90.23% after 5 cycles of use. The adsorption mechanism of Pb(II) included ion-exchange interaction, as well as chelation interactions of Pb–O, Pb–NH2, and Pb–S. The versatile combination of defect engineering and composite beads provides novel inspirations for MOF modification for boosting heavy metal adsorption.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanomaterials
·
2024
·Vol. 14
·期 23
·1925
·
IF 4.4
Yi Hu,Hongwei Wang,Xianliang Ren,Fang Wu,Gaobin Liu,Shufang Zhang,Haijun Luo,Liang Fang
Pore structural regulation is expected to be a facile way to enhance the adsorption performance of MXene. In this work, spherical foam composites consisting of Ti3C2Txand sodium alginate (SA) were synthesized via a vacuum freeze-drying technique. By varying the solution volume of Ti3C2Tx, four distinct Ti3C2Tx@SA spherical foams with honeycomb-like and lamellar structures with a pore diameter in the range of 100–300 μm were fabricated. Their methylene blue (MB) adsorption performances were then systematically compared. The results revealed that the honeycomb-like porous-structured spherical foams have a significantly higher adsorption capacity than their lamellar counterparts. Notably, the Ti3C2Tx@SA honeycomb-like porous foam exhibited a remarkable maximum adsorption capacity (qm) of 969 mg/g, positioning it at the forefront of MB adsorbent materials. Respective analysis of the adsorption kinetics, thermodynamics, and isotherm model indicated that this MB adsorption of Ti3C2Tx@SA honeycomb-like porous foam is characterized to be a physical, endothermic, and monolayer adsorption. The Ti3C2Tx@SA honeycomb-like porous foam also demonstrated excellent resistance to ion interference and good reusability, further attesting to its substantial potential for practical applications. X-ray photoelectron spectroscopy (XPS) analysis was employed to elucidate the adsorption mechanism, which was found to involve the synergistic effect of electrostatic adsorption and amidation reaction. This work not only offers new avenues for the development of high-performance adsorption materials but also provides crucial insights into the structural design and performance optimization of porous materials.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）