INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2019
·
IF 4.784
Kewang Zheng,Wei Li,Wei Wang,Hujian Chen,Chaofan Huang,Qiaolin Ren,Caiqin Qin
Adsorption of metal impurities from transformer oil was studied using a novel porous membrane. A solution of N , O ‑carboxymethyl‑chitosan (CMC) and sodium phytate (SP) was blended to prepare a novel porous membrane for the metal impurities adsorption from transformer oil. The chemical structure of the membranes was characterised by their FTIR spectra, scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and video camera observations. The effects of the SP content of the membrane, contact time, and contact temperature on adsorption of copper, iron, and aluminium impurities were studied. The FTIR spectra and thermogravimetric curves of the membranes indicated good compatibility between CMC and SP. The SEM and video camera observations suggested that CMC-SP composite membranes had a mature, porous structure. The experimental results showed that the SP content significantly affected the adsorption capacity of a CMC membrane. The maximum adsorption percentages of elemental copper, iron, and aluminium were 88.12%, 82.35%, and 80.36% when the SP ratio was 80% at 60 °C.
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POLYMER TESTING
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2019
·
IF 2.943
Ning Yan,Xiao-Fang Wan,Xin-Sheng Chai
This paper reports on a novel method for rapid determination of the degree of deacetylation (DD) of chitosan samples by headspace gas chromatography (HS-GC). In this method, overdose of an acid is added to protonate the free amino groups in chitosan, which further reacts with bicarbonate (as an alkali titrant) in a close vial. Based on measuring the HS-GC signal for CO 2 vs. the volume of HCO 3 − added by a stepwise titration, two transition points can be obtained. The DD value is calculated by net volume of HCO 3 − consumed, i.e., by the R NH 3 + groups in chitosan. The results showed that the present method has a good measurement precision (RSD < 0.82%) and accuracy (relative differences < 6.46% when compared with the results measured by a reference method). Since the HS-GC can perform an automated sample reaction equilibration and measurement, it could be much more efficient than the existing methods in the batch sample analysis.
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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2019
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IF 4.784
Shuchun Gan,Bo Xu,Xiong Zhang,Jianhao Zhao,Jianhua Rong
Physically cross-linked double-network (DN) hydrogels are capturing more and more attention due to their good mechanical properties and self-recovery ability. However, they usually suffer from complicated preparation process and fussy performance regulation, which severely limit their applications in many fields. Herein, we fabricated a physically cross-linked poly(vinyl alcohol)-(2-hydroxypropyltrimethyl ammonium chloride chitosan) (PVA-HACC) DN hydrogels without organic solvents or toxic cross-linking agents via a simple two-step method of freezing/thawing and immersion processing. The effects of immersion time and concentration of Na 3 Cit solution on the structures and mechanical properties of the hydrogels were investigated. The obtained hydrogels exhibited excellent mechanical properties including high elastic modulus (1.44 MPa), high strength (a maximal tensile fracture stresses of 4.14 MPa and a maximal compressive stresses of over 70 MPa at 98% strain), and superior fracture toughness (17.09 MJ/m 3 ). In addition, good self-recovered property and anti-fatigue performance were realized for the hydrogels owing to the reversible HACC ionic networks. The preparation of PVA-HACC DN hydrogels offers a new guidance for the design and synthesis of environmentally friendly DN hydrogels with outstanding mechanical properties and broad application prospects.
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ACS Biomaterials Science & Engineering
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2019
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IF 4.511
Ruitao Zou,Suyan Shan,Libin Huang,Zhi Chen,Tom Lawson,Mimi Lin,Lu Yan,Yong Liu
The noninvasive and real-time detection of glucose sugar from tears is promising for the early diagnosis and treatment of chronic diseases such as diabetes. However, its realization is a big challenge. A suitable biosensor electrode that can closely fit the eye and be electrochemically sensitive is still unrealized. In this work, nitrogen-doped graphene (N-G) was used as an ophthalmic electrode in a high-performance intraocular biosensor. The use of N-G has been reported elsewhere before as it is highly electroactive and so has a particular use in biosensors. We hereby present a novel procedure for making carboxylated chitosan-functionalized nitrogen-containing graphene (GC–COOH) by using a one-step ball-milling process. This process does not use toxic chemicals, flammable gases, or a high temperature. It is thus particularly easy to perform. The fabricated nanomaterial had a high electroactivity and was easily assembled as a glucose biosensor by the immobilization of glucose oxidase. The thus constructed biosensor has a high sensitivity at 9.7 μA mM–1 cm–2, a broad linear range at 12 mM, and a good detection limit of 9.5 μM. It was able to maintain this activity after a month of storage. We also report the intraocular use of this constructed biosensor. The as-prepared GC–COOH was found to be highly biocompatible to ophthalmologic cells such as corneal epithelial and retinal pigment epithelium cells. No change in the intraocular pressure or the corneal structure was measured in a New Zealand white rabbit model. The as-assembled sensor was worn by the animals for more than 24 h without undue impact. This result confirmed the biosensor’s potential for intraocular application in the clinic. Its assembly into a useful sensor shown here has great potential to provide real-time monitoring of glucose levels in tear fluids of patients with high sugar levels.
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CARBOHYDRATE POLYMERS
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2019
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IF 6.044
Maruthupandy Muthuchamy,Rajivgandhi Govindan,Kadaikunnan Shine,Veeramani Thangasamy,Naiyf S. Alharbi,Muneeswaran Thillaichidambaram,Jamal M. Khaled,Jun-Li Wen,Khalid F. Alanzi
In this study graphene/chitosan nanoparticles (GR/CS NCs) were developed. The homogenous combination of GR and CS was confirmed by FTIR spectroscopy. The combination of CS with GR sheets reduced the XRD intensity of the GR peak in GR/CS NCs, while TEM images revealed the immobile CS coating of GR sheets. Further, the anti-biofilm activity of GR/CS NCs was tested. The tests showed that the formation of biofilm by Pseudomonas aeruginosa and Klebsiella pneumoniae was inhibited at 40□g/mL GR/CS NCs up to 94 and 92 %, respectively. The intracellular and cell surface damage of the bacteria was observed by CLSM and SEM. Also, GR/CS NCs produced a toxic effect of 90 % on Artemia franciscana at 70□g/mL upon 24 h incubation. The recorded properties of the synthesized GR/CS NCs qualify them as potential agents against multi-drug resistant bacteria.
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Nanotechnology Reviews
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2019
·Vol. 8
·期 1
·645-660
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IF 2.759
Yu Miao,Jiawei Lu,Junhui Yin,Changchun Zhou,Yaping Guo,Shumin Zhou
Melanoma is the most lethal dermal tumor, and a high recurrence rate and skin defects are two main serious problems. An antimelanoma material,which effectively inhibits tumor recurrence and possesses excellent biocompatibility, is urgently needed to treat melanoma. In this study, we developed a novel antitumor Yb 3+ [Yb(NO 3 ) 3 ]containing chitosan hydrogel (Yb-CS hydrogel) by dissolving Yb(NO 3 ) 3 and chitosan in acetic acid solution and forming composite hydrogels by a freeze-drying process after adding NaOH to the mixed solution. In vitro studies demonstrated that the Yb 3+ produces effect of inducing cell death in Yb-CS hydrogel. Moreover, we found that the Yb-CS hydrogel inhibited a focal adhesion kinase (FAK)-dependent signaling pathway and induced B-16 cell anoikis. However, the Yb-CS hydrogel was less effective on L929 normal mouse dermal cells. In vivo studies showed that the Yb-CS hydrogel inhibited the recurrence of melanoma in a mouse bare xenograft tumor model. We concluded that the Yb-CS hydrogel could potentially be used in the antimelanoma field, especially in the inhibition of melanoma recurrence.
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FOOD CHEMISTRY
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2019
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IF 5.399
Tiantian Min,Zhu Zhu,Xiaoli Sun,Zhipeng Yuan,Junwei Zha,Yongqiang Wen
In this work, a multifunctional food packaging composite coating with transparent, biodegradable, antifogging and antibacterial properties was designed and fabricated by quaternary ammonium salt modified chitosan (HACC) and poly (vinyl alcohol) (PVA) via a facile and environment-friendly solution casting method. A simple quaternization modification enabled the coating simultaneously to achieve excellent antifogging and antibacterial functions. The excellent antifogging property of the HACC/PVA composite coating was attributed to the strong water absorbency of quaternary ammonium chitosan and PVA. A nearly 98% transmittance ratio of coated glasses was achieved during antifogging test. In addition, the inhibition rate of the HACC/PVA composite coating kill against Escherichia coli ( E. coli ), Staphylococcus aureus ( S. aureus ) and Botrytis cinerea were up to ~99%. The antibacterial effect was demonstrated by each group of strawberries after storage for 1, 3, 5 days. The multifunctional coating has broad prospects in the application of fruit and vegetable packaging.
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JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
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2019
·Vol. 322
·期 2
·553-559
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IF 1.186
Wu Peng,Wang Yun,Li Yang,Hu Xuewen,Xiu Taoyuan,Yuan Dingzhong,Liu Yan,Wu Zhenyu,Liu Zhirong
In order to reduce the potential toxicity to the environment after treatment of radioactive waste water, an eco-friendly graphene oxide nanoribbons/chitosan (GONRs-CTS) composite was prepared and utilized for adsorption of Th(IV) from aqueous solution. The GONRs-CTS adsorbent was characterized by XRD, FTIR and SEM, indicating that GONRs-CTS contains a large amount of oxygen-containing groups and chitosan was successfully attached to the GONRs surface. The Th(IV) adsorption on GONRs-CTS was endothermic and spontaneous, with the maximum single layer adsorption capacity was 140.6 mg g −1 at pH = 3.0, in the contact time of 12 h. The adsorption process was consistent with pseudo-second-order kinetics and the Langmuir isotherm model.
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CELLULOSE
·
2018
·Vol. 25
·期 8
·4831-4840
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IF 3.809
Li Ya Dan,Li Wan Yun,Chai Hui Hui,Fang Can,Kang Yue Jun,Li Chang Ming,Yu Ling
Cotton thread has been proposed as a new, economically affordable material for the fabrication of microfluidic circuits for use in fast, low-cost, point-of-care diagnostic testing devices. In this work, chitosan, a biocompatible polymer, was used to modify cotton thread to improve its fluidic properties for microfluidic applications. Electrostatic-interaction-mediated adsorption of chitosan on alkaline-scoured thread can effectively increase thread’s solution hydrophilicity and wicking rate. Moreover, the proposed process conserves the thread’s hydrophilicity and fluidic properties even when stored for several months. As a microfluidic platform for enzymatic-reaction-associated colorimetric measurement, the suggested chitosan modification results in the accumulation of more analyte in the detection zone because of the improved flow rate, which enhances the colorimetric signal intensity. In this study, a glucose oxidase-mediated colorimetric glucose assay was demonstrated on a chitosan-modified microfluidic thread-based analytical device (μTAD). A linear range of 1–7.5 mM, a low detection limit of 0.2 mM, and a recovery rate between 93 and 98% was achieved in detecting glucose in artificial urine samples.
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ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
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2018
·Vol. 25
·期 18
·17830-17841
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IF 2.8
Wan Zhonghao,Li Meng,Zhang Qian,Fan Zixi,Verpoort Francis
Magnetic chitosan particles (MCS) were chemically grafted by m-phenylenediamine (mPD) forming a distinctive shell layer with abundant nitrogenous functional groups and used as an adsorbent for the effective removal of Cr(VI) from aqueous solution. By interaction among functional groups in the facile oxidative polymerization process, the grafting of mPD and its polymers on MCS surface was innovatively realized. Through Fourier-transformed infrared spectroscopy, energy dispersive spectrometer, X-ray photoelectron spectroscopy, etc., the chemical properties of MCS before and after modification were characterized and the concurrent reduction-adsorption mechanism in Cr(VI) adsorption by mPD-MCS was carefully analyzed. The maximal Cr(VI) removal performance of mPD-MCS reached 227.27 mg/g, which was significantly better than that of the original MCS. The analysis indicated that Cr(VI) could be efficiently reduced to Cr(III) and the removal of Cr(VI) and Cr(III) was through adsorption and chelation simultaneously by mPD-MCS. Results also indicated that the concurrent reduction-adsorption was enhanced by protonation of nitrogenous functional groups under low pH. The obtained results suggest that mPD-MCS has a good potential in removal and detoxication of Cr(VI) from aqueous solutions.
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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2018
·
IF 3.909
Xin Wang,Le He,Bing Wei,Guoqing Yan,Jun Wang,Rupei Tang
Tumor extracellular matrix (ECM) still remains a major barrier that hinders the diffusion of drug in tumor parenchyma. We design a lactobionic acid (LA) and bromelain dual-functional nanoparticles as doxorubicin carriers. LA can increase the nanoparticles' tumor-targeting ability, while bromelain can enhance the permeation of nanoparticles in tumor parenchyma due to the hydrolytic activity to ECM. The chemical structures of these modified macromolecules were characterized by 1 H NMR, FT-IR and UV spectrum. Drug-loaded nanoparticles as final drug formulations were observed in terms of size, zeta potential and micromorphology. Monolayer cells and three-dimensional cell spheroids were used to investigate the influence of LA and bromelain on the nanoparticles' cellular uptake, cytotoxicity, accumulation and penetration. In vivo drug distribution and antitumor activity results demonstrated that bromelain increased nanoparticles penetration and diffusion ability in tumor area upon the digestion of ECM, leading to higher drug concentration in tumor area and superior antitumor effect.
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HYDROMETALLURGY
·
2018
·
IF 3.3
Qiaoling Xie,Tao Lin,Fuming Chen,Dandan Wang,Bo Yang
Sulphur-containing chitosan, a water-soluble derivative of chitosan, was synthesized by using chitosan and other reagents. This sulphur-containing chitosan was combined with chitosan to recover ultra-trace palladium in HCl medium. The effects of the chelating dosages, pH, chelating precipitation rate, initial Pd concentration and coexisting cations were systematically investigated via chelating precipitation experiments. Under the optimized conditions, greater than 95% of palladium was recovered from the HCl medium, with pH ranging from 2 to 5.5 and proper dosages of chitosan and sulphur-containing chitosan, which were related to the concentration of Pd(II) ions. In addition, the presence of coexisting cations (Cu 2+ , Ni 2+ , Fe 2+ , and Sn 2+ ) had no effect on the recovery rate of palladium. The recovery mechanism of palladium by chitosan and sulphur-containing chitosan was studied via molecular weight analyses, elemental analyses, FT-IR analyses and XPS analyses. The proposed chelating precipitation method was successfully applied to the recovery of ultra-trace palladium in HCl medium.
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