查找使用阿拉丁产品的科研文献

“One-pot” preparation and adsorption performance of chitosan-based La3+/Y3+ dual-ion-imprinted thermosensitive hydrogel

Kaiqi Ding,Ying You,Liweng Tang,Xinyue Zhang,Ziyu Qin,Xueqiong Yin

Temperature-sensitive materials are increasingly of deep interest to researchers. Ion imprinting technology is widely used in the field of metal recovery. In order to solve the problem of rare earth metal recovery, we designed a temperature-sensitive dual-imprinted hydrogel adsorption product (CDIH) with chitosan as the matrix, N-isopropylacrylamide as a thermally responsive monomer , and La 3+ and Y 3+ as the co-templates. The reversible thermal sensitivity and ion-imprinted structure were determined by differential scanning calorimetry , Fourier transform infrared spectrometer, Raman spectra , Thermogravimetric analysis , X-ray photoelectron spectroscopy , Scanning electron microscopy and X-ray energy spectroscopy various characterizations and analyses. The simultaneous adsorption amount of CDIH for La 3+ and Y 3+ was 87.04 mg/g and 90.70 mg/g, respectively. The quasi-secondary kinetic model and Freundlich isotherms model well described the adsorption mechanism of CDIH. It's worthy to mention that CDIH could be well regenerated through washing with deionized water at 20 °C, with a desorption rate of 95.29 % for La 3+ and 96.03 % for Y 3+ . And after 10 cycles of reuse, 70 % of the adsorption amount could be maintained, revealing excellent reusability. Furthermore, CDIH expressed better adsorption selectivity to La 3+ and Y 3+ than its non-imprinted counterparts in a solution containing six metal ions .

A chitosan-optimized polyethyleneimine/polyacrylic acid multifunctional hydrogel for reducing the risk of ulcerative arterial bleeding

Panxianzhi Ni,Sheng Ye,Shuting Xiong,Meng Zhong,Jing Shan,Tun Yuan,Jie Liang,Yujiang Fan,Xingdong Zhang

Ulcerative arterial bleeding is characterized by sudden onset, rapid disease development, and high mortality, which is a great challenge for clinicians to treat, specially bleeding in areas where endoscopic operation is difficult, or in the case of diffuse bleeding, tumor bleeding, and recurrent bleeding. Herein, we proposed a novel treatment strategy using biomaterials to protect the wound and isolate the erosion of digestive tract contents to prevent arterial bleeding in advance. By introducing chitosan to construct multihydrogen-bonding and an electrostatic interaction system, we developed polyethyleneimine/polyacrylic acid/chitosan (PEI/PAA/CS) multifunctional hydrogel. The new hydrogel is characterized by ultrafast gelation, strong tissue adhesion, gastric acid resistance, burst resistance, biocompatibility, hemostasis, and tissue repair. The addition of CS significantly improved the tissue adhesion, biocompatibility, hemostasis, and tissue repair ability of the hydrogel. The PEI/PAA/CS hydrogel could adhere to the ulcer surface and form a protective layer on the wound to prevent arterial bleeding. Importantly, the PEI/PAA/CS hydrogel also has the ability to stop bleeding and promote wound repair, which has been demonstrated in a variety of hemorrhage models in rats and rabbits. All of these factors indicate that the PEI/PAA/CS hydrogel is a promising biomaterial for reducing the risk of ulcerative arterial bleeding.

A lubricant and adhesive hydrogel cross-linked from hyaluronic acid and chitosan for articular cartilage regeneration

Haofeng Qiu,Junjie Deng,Rufang Wei,Xiang Wu,Shengjia Chen,Yanyu Yang,Chenyang Gong,Lingling Cui,Zhangyong Si,Yabin Zhu,Rong Wang,Dangsheng Xiong

Trauma-induced articular cartilage damages are common in clinical practice. Hydrogels have been used to fill the cartilage defects and act as extracellular matrices for cell migration and tissue regeneration. Lubrication and stability of the filler materials are essential to achieve a satisfying healing effect in cartilage regeneration. However, conventional hydrogels failed to provide a lubricous effect, or could not anchor to the wound to maintain a stable curing effect. Herein, we fabricated dually cross-linked hydrogels using oxidized hyaluronic acid (OHA) and N -(2-hydroxypropyl)-3-trimethylammonium chitosan chloride (HTCC) methacrylate (HTCCMA). The OHA/HTCCMA hydrogels, which were dynamically cross-linked and then covalently cross-linked by photo-irradiation, showed appropriate rheological properties and self-healing capability. The hydrogels exhibited moderate and stable tissue adhesion property due to formation of dynamic covalent bonds with the cartilage surface. The coefficient of friction values were 0.065 and 0.078 for the dynamically cross-linked and double-cross-linked hydrogels, respectively, demonstrating superior lubrication. In vitro studies showed that the hydrogels had good antibacterial ability and promoted cell proliferation. In vivo studies confirmed that the hydrogels were biocompatible and biodegradable, and exhibited a robust regenerating ability for articular cartilage. This lubricant-adhesive hydrogel is expected to be promising for the treatment of joint injuries as well as regeneration.

The mimicked cell penetration peptides of chitosan derivates with low molecular weight for transdermal enhancement studies

Jianhua Lv,Meihua Jiang,Yaru Fang,Wenchang Zhang,Mi Wu,Fanghao Zheng,Kaijun Lei,Lei Shang,Yan Zhao

The biomimetic chitosan derivatives synthesized by chemical coupling of L-arginine onto chitosan with low molecular weight, named Arg-CS, which was prepared by mimicking the arginine-rich peptides, to achieve the permeability performance of Cell-penetrating peptides (CPPs). The physicochemical properties of the Arg-CSs were characterized via Attenuated total reflection Fourier transform infrared (ATR-FTIR) and 1 H-nuclear magnetic resonance spectroscopy ( 1 H NMR), and high-performance liquid chromatography (HPLC). The thermal stability of Arg-CS was improved by approximately 80 °C, compared to the pure chitosan. The maximum cumulative amounts of aspirin for Arg-CS 4.7 k, Arg-CS 5.2 k, and Arg-CS 6.3 k were 32.85 µg/cm 2 , 22.98 µg/cm 2 , and 17.51 µg/cm 2 at 8 h, respectively, presenting a phenomenon of increasing of aspirin permeation with decreasing molecular weight of Arg-CS. Arg-CS with low molecular weight was more conducive to improve the penetration of aspirin by changing the secondary structure of keratin from β-sheets to random coil. The molecular docking also suggested that Arg-CS had stronger affinity to keratin by strong hydrogen bond interactions. These results indicated that the nonirritant and thermally stable Arg-CS with lower molecular weight can be used to enhance the permeation of aspirin and applied in the field of transdermal drug delivery.

Antimicrobial and Mechanical Properties of Ag@Ti3C2Tx-Modified PVA Composite Hydrogels Enhanced with Quaternary Ammonium Chitosan

Linxinzheng Guo,Kun Hu,Haibo Wang

Polyvinyl alcohol (PVA) is a polymeric material with good biocompatibility, excellent hydrophilicity, and a large number of hydroxyl groups. However, due to its insufficient mechanical properties and poor inhibition of bacteria, it has a lack of applications in wound dressings, stent materials, and other fields. In this study, a simple method was used to prepare composite gel materials: Ag@MXene-HACC-PVA hydrogels with a double-network structure were prepared using an acetal reaction. Due to the double cross-linked interaction, the hydrogel has good mechanical properties and is resistant to swelling. The adhesion and bacterial inhibition were enhanced due to the addition of HACC. In addition, the strain sensing properties of this conductive hydrogel were stable, and the GF (specification factor) was 1.7617 at 40–90% strain. Therefore, the dual-network hydrogel with excellent sensing properties, adhesion properties, antibacterial properties, and cytocompatibility has potential applications in biomedical materials, especially as a tissue engineering repair material.

Multifunctional hydrogel wound dressing with rapid on-demand degradation property based on aliphatic polycarbonate and chitosan

Qida Zong,Xinxuan Peng,Yan Ding,Huiying Wu,Chang Lu,Jing Ye,Wei Sun,Jinwei Zhang,Yinglei Zhai

The multifunctional hydrogel dressings are effective strategy to treat chronic wounds of diabetes. In addition, the ability of selective degradation on demand to change dressings could provide better patient compliance. Here, an injectable, self-healing hydrogel with rapid degradability on-demand is designed to promote the healing of diabetes wounds. The block copolymer formed by aldehyde modified aliphatic cyclic carbonate monomer with polyethylene glycol (MBP) and chitosan (CS) were crosslinked through the Schiff base bond to obtain a hydrogel with excellent injectability and self-healing ability. Due to the presence of carbonate bonds in MBP, it showed the rapid on-demand degradation characteristics triggered by N -acetylcysteine (NAC). At the same time, gallic acid (GA) was loaded into the hydrogel, giving the hydrogel dressing antioxidant. In vivo and in vitro experiments showed that the hydrogel wound dressing possesses good natures, such as antibacterial, antioxidant, and friendly cell compatibility, which could promote wound healing. Overall, the multifunctional hydrogel wound dressings with rapid on-demand degradation characteristics are more practical for clinical applications.

Construction of carboxymethyl chitosan-based nanoparticles of hypoxia response for co-loading doxorubicin and tanshinone IIA

Mengli Lu,Li Ma,Juncan Li,Jie Li,Miao Tong,Fuli Dai,Feiyu Song,Xueqiong Zhang,Tong Qiu

As a first-line drug for breast cancer chemotherapy, the effectiveness of doxorubicin (DOX) is challenged by high doses and high toxicity. Studies showed the combination of Tanshinone IIA (TSIIA) and DOX could enhance the efficacy of DOX for cancer and reduce the toxic effects to normal tissues. Unfortunately, free drugs are easily metabolized in the systemic circulation, which are less prone to aggregation at the tumor site to exert anticancer efficacy. In present study, we prepared a carboxymethyl chitosan-based hypoxia-responsive nanoparticles loaded with DOX and TSIIA for the treatment of breast cancer. The results demonstrated that these hypoxia-responsive nanoparticles not only improved the delivery efficiency of the drugs but also enhanced the therapeutic efficacy of DOX. The average size of nanoparticles was about 200–220 nm, the optimal drug loading and encapsulation efficiency of TSIIA in DOX/TSIIA NPs were 9.06 % and 73.59 %, respectively. Hypoxia-responsive behavior were recorded in vitro, while the synergistic efficacy is significantly exhibited in vivo and the tumor inhibitory rate was 85.87 %. Notably, TUNEL assay and immunofluorescence staining verified that the combined nanoparticles exerted a synergistic anti-tumor effect by inhibiting tumor fibrosis, decreasing the expression of HIF-1α and inducing tumor cell apoptosis. Collectively, this carboxymethyl chitosan-based hypoxia-responsive nanoparticles could have promising application prospect for effective breast cancer therapy.

A ROS-response hyaluronic acid-coated/chitosan polymer prodrug for enhanced tumour targeting efficacy of SN38

Jianpeng Qin,Meng Sun,Yanli Zhen,Ji Li,Dongkai Wang

Softening and enriching polarity of chitosan backbone as a bifunctional binder for high-performance sulfur cathode

Sai-Sai Deng,Li Deng,Zong-Kui Liu,Jun-Ke Liu,Jing Zhang,Shi-Jun Xie,Ming-Jia Guo,Yao Zhou,Jun-Tao Li

Lithium-sulfur batteries have attracted much attention because of their high energy density; their long-term stability suffers from the shuttle effect of polysulfides and the volume variation of sulfur during charging and discharging process. Herein, by chemically grafting highly flexible and polar poly(N-aryloylglycamide) (PNAGA) segments onto the linear backbone of the naturally abundant, hard and brittle chitosan, a hyper-branched and 3D-linked aqueous binder was prepared, which has stronger binding strength and is more flexible than the pristine chitosan or the commercial PVDF . Moreover, owing to the presence of affluent diamide groups in the PNAGA branches, the grafted binder demonstrates much better ability for capturing polysulfides. When applied in sulfur cathode, the binder is bifunctionally effective, which can suppress the shuttle behaviors of the polysulfides and well maintain the interfacial intimacy, thus enabling excellent long-term cycling stability. After 300 cycles at 0.2 C, the relevant battery still retains 843.1 mAh g  −   1 , spelling a retention rate 49.4% and 69.6% higher than those using PVDF and the pristine chitosan, respectively; even under a high sulfur loading of 5.2 mg cm −2 , the battery can still operate steadily more than 100 cycles at 0.2 C, maintaining a specific capacity above 620.1 mAh g  −   1 .

Preparing bright Monascus yellow pigments by loading quercetin-Sn(II)- albumin –chitosan: Enhanced stability and bioactivity

Zhenfeng Huang,Huixin Xie,Tingting Hu,Jiarui Zeng,Xiaofei Tian,Zhenqiang Wu

Natural Monascus yellow pigments (MYPs) have received considerable attention due to their great safety and biological activities, but their unsatisfactory color tonality and stability limit their applications. A novel encapsulate system for hydrophilic yellow pigments (HYPs) were investigated through stable ternary nanocomplexes using quercetin-Sn (II), bovine serum albumin (BSA), and chitosan (CS) in this work. Layer-by-layer assembly preparation of HYPs-loaded quercetin-Sn (II)-BSA-CS nanocomplexes were verified by fluorescence spectroscopy, fourier transform infrared spectroscopy , X-ray photoelectron spectra, and 1 H nuclear magnetic resonance. A hyperchromic effect on HYPs was obtained since their maximum ultraviolet absorption wavelength redshifted from 352 nm to 364 nm first due to the interaction with quercetin-Sn (II) and further redshifted to 408 nm due to ternary conjugation, greatly improved the color tonality and dye-uptake. The HYPs-loaded nanocomplexes showed irregular glomerate nanosphere with 252–382 nm of particle size. Their conjugation remitted HYPs degradation under various environmental stresses (thermal, light, and ascorbic acid treatment), and had a great color stability response to pH change. Higher lipid-lowering and antioxidant activities were detected in the nanocomplexes than free HYPs. This study provides a new way for fabricating novel MYPs with great physicochemical stability, bright color and hypolipidemic activities.

Improved hydrophobicity, antibacterial and mechanical properties of polyvinyl alcohol/quaternary chitosan composite films for antibacterial packaging

Fengsong Liu,Xiaowei Zhang,Xinglong Xiao,Qingfei Duan,Hong Bai,Yifang Cao,Yan Zhang,Mahafooj Alee,Long Yu

Polyvinyl alcohol (PVA) and chitosan (CS) are attractive polymeric feedstocks for developing eco-environmental materials. In this work, a biodegradable and antibacterial film was developed based on PVA blending with different long-chain alkyl and different contents of quaternary chitosan through solution casting, in which quaternary chitosan not only acted as an antibacterial agent but also improved hydrophobicity and mechanical properties. A novel peak appeared at 1470 cm −1 in Transform Infrared Spectroscopy (FTIR) and a new C Cl bond spectral peak at 200 eV in X-ray photoelectron spectroscopy (XPS) spectra suggested that CS was successfully modified by quaternary. Besides, the modified films have better antibacterial effects against Escherichia ( E. coli ) and Staphylococcus ( S. aureus ) and present stronger antioxidant properties. Optical properties demonstrated that the light transmittance on both UV and visible light showed a decreasing trend with the increase of the quaternary chitosan contents. Whereas the composite films have enhanced hydrophobicity than PVA film. Furthermore, the composite films had higher mechanical properties, in which Young's modulus , tensile strength , and elongation at break were 344.99 MPa, 39.12 MPa, and 507.09 %, respectively. This research demonstrated that the modified composite films could extend the shelf of life on antibacterial packaging.

Development of propolis extract-loaded nanoparticles with chitosan and hyaluronic acid for improving solubility and stability

Do Hee Kim,Eun Woo Jeong,Youjin Baek,Hyeon Gyu Lee

Propolis extract (PE) is a natural polyphenol with various biological activities; however, its application is limited due to low solubility and instability. To overcome these drawbacks, we encapsulated PE in nanoparticles (PE-loaded nanoparticles, PE-NP) using chitosan (CS) and hyaluronic acid (HA) as wall materials. We examined the physicochemical characteristics (size, polydispersity index, zeta potential, and entrapment efficiency) of PE-NP prepared with the various ratios of CS to HA and core to the wall material, and confirmed the optimal ratio for the formulation of PE-NP as 4:7 and 1:2, respectively. In addition, PE-NP significantly increased the solubility of PE by 2.43-fold compared to that of free PE ( p  < 0.05). Moreover, the retention rate of total flavonoid content (TFC) in PE-NP was significantly higher than that in free PE after the heat treatment (90 °C) for 24 h ( p  < 0.05). Furthermore, PE-NP showed significantly higher retention rates of TFC and DPPH radical scavenging effects than free PE after storage for 4 weeks at 30 and 50 °C ( p  < 0.05). In conclusion, these findings suggest that PE-NP may be a promising approach to enhance the solubility and stability of PE and could provide helpful information for expanding the application of PE.