CARBOHYDRATE POLYMERS
·
2010
·
IF 3.167
Kai Liu,Xiao-feng Li,Xiao-min Li,Bei-hai He,Guang-lei Zhao
Pectins or polygalacturonic acids (PGA) were originated from alkaline peroxide bleaching of mechanical pulps and considered as the dominant troublesome substance, which seriously decreased the runability of the paper machine in process water closure. To find wide application of enzymes in lowering PGA concentration in papermaking industries, cross-linked chitosan beads were prepared. Results showed that the PGA-absorption capability of chitosan beads was greatly affected by its cross-linking degree. The activity of immobilized pectinase on cross-linked chitosan beads were also investigated and the highest activity of binary immobilized pectinase on cross-linked chitosan was achieved using 1.00% of activating reagent or 0.005% of glutaraldehyde. Cationic demand of PGA solutions was obviously lowered by increasing the temperature of enzymatic treatment. GPC analysis showed a sharp decrease in the molecular weight of PGA after enzymatic treatment. Besides, operational stability of the immobilize pectinase was analyzed to evaluate its application potential.
研究领域:
制浆造纸工程
·
生物化学与分子生物学
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产品关联
DOI
高影响因子
BIOMACROMOLECULES
·
2024
·
IF 5.5
Zhimin Luo,Yunan Yuan,Ling Li,Dayang Xie,Chong Liu,Tong Li,Zhaopei Guo,Kai Hao,Yanhui Li,Huayu Tian
Poly(amino acid)s (PAAs) are one kind of favorable biopolymer that can be used as a drug or gene carrier. However, conventional ring-opening polymerization of PAAs is slow and needs a strict anhydrous environment with an anhydrous reagent as well as the product without enough high molecular weight (Mn), which limits the expanding of PAAs’ application. Herein, we took BLG-NCA as the monomer to quickly synthesize one kind of high Mn amphiphilic copolymer, poly(ethylene glycol)-b-poly(γ-benzyl-l-glutamic acid) (PEG-PBLG), by relay polymerization with a simple one-pot method within 3 h in mild conditions (open air, moisture insensitive). In the polymerization process, ring-opening polymerization-induced self-assembly in sodium bicarbonate aqueous solution first occurred to obtain low Mn PEG-PBLG seeds without purification. Then γ-benzyl-l-glutamate N-carboxyanhydride (BLG-NCA) dichloromethane solution was added into PEG-PBLG seeds directly and stirred vigorously to form am emulsion; during this process, the amphiphilic PEG-PBLG seeds will anchor on the interface of DCM and water to ensure the concentration of α-helix rigid PBLG in DCM to maintain the following relay polymerization. Then, high Mn PEG-PBLG was obtained in mild conditions in one pot. We found that the α-helix rigid structure was essential for relay polymerization by studying the synthetic speed of amphiphilic copolymer with different secondary structures. MOE simulation results showed that PBLG and BLG-NCA tended to form a double hydrogen bond, which was beneficial to relay polymerization because of higher local concentrations that can produce more double hydrogen bonds. Our strategy can quickly obtain high Mn PEG-PBLG (224.9 KDa) within 3 h from PEG-NH2 and BLG-NCA in one pot and did not need an extra initiator. After deprotection, the poly(ethylene glycol)-b-poly(l-glutamate acid) (PEG-PGA) with high Mn as a second product can be used as an excellent antitumor drug carrier. The high Mn PEG-PGA can achieve an encapsulation rate of 86.7% and a drug loading rate of 47.3%, which is twice that of the low Mn PEG-PGA. As a result, the synthesis of PEG-PBLG by relay polymerization simplified the process of PEG-PAA polymerization and increased the Mn. In addition, this method opened a way to obtain other kinds of high Mn PEG-PBLG values in the future.
研究领域:
聚合物化学
·
材料科学
·
药学
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产品关联
DOI
PubMed
高影响因子
Materials Today Advances
·
2026
·
IF 8
Jiabao Xiong,Yuan Wang,Lijun Zhu,Zhong Du,Le Guo,Jiayi Ding,Chi Zhang,Siyiti Amuti,Junhua Hu,Chao Wang,Biao Dong,Nuernisha Alifu
Overcoming thermoresistance and achieving precise, efficient tumor therapy remain major challenges. Heat shock protein 70 (HSP70) expression and autophagy activation are two major cellular defense mechanisms associated with thermal resistance. However, strategies that target both mechanisms to improve tumor treatment efficacy remain limited. Herein, this study presents a novel type of near-infrared II (NIR-II)-responsive theranostic nanoplatform (IR-820@γ-PGA/Arg NPs, PIRA NPs) that integrates photothermal therapy (PTT), photodynamic therapy (PDT), nitric oxide (NO)-mediated gas therapy (GT), and dual-pathway inhibition mechanisms to overcome thermal resistance. The theranostic nanoplatform utilizes a γ-polyglutamic acid (γ-PGA) to encapsulate the NIR-II dye IR-820, which forms stable J-aggregates to improve NIR-II fluorescence emission and photothermal conversion efficiency. The nanoplatform adsorbs L-arginine (Arg) and releases NO under 808 nm laser excitation, exhibiting excellent photothermal properties and NIR-II fluorescence emission for precise tumor treatment. PIRA NPs overcome photothermal resistance via two pathways: suppressing HSP70-mediated thermoresistance and disrupting the autophagy-lysosomal degradation pathway (LC3B/p62 axis) through Arg-derived NO generation. This dual-pathway blockade effectively neutralizes tumor defenses, achieving a 92.7% tumor inhibition rate with minimal systemic toxicity. The γ-PGA framework enhances the stability of J-aggregates and their biocompatibility, further improving therapeutic efficacy. This work provides a versatile nanotherapeutic platform based on a promising strategy for reversing thermoresistance and achieving highly efficient cancer therapy.
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产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2019
·
IF 6.044
Zongrui Tong,Jueying Yang,Lizhi Lin,Ruiqi Wang,Bin Cheng,Yu Chen,Liansheng Tang,Jianying Chen,Xilan Ma
In the present work, a poly(γ-glutamic acid)/alginate/silver nanoparticle (PGA/Alg/AgNP) composite microsphere with excellent antibacterial and hemostatic properties was prepared by the in situ UV reduction and emulsion internal gelation method, and its potential application for antibacterial hemostatic dressing was explored. Well dispersed AgNPs were in situ synthesized by a UV reduction method with alginate as stabilizer and reductant. The AgNPs showed excellent antibacterial activities against both gram-negative and gram-positive bacteria. Additionally, the AgNPs prepared by the in-situ UV reduction exhibited better biocompatibility and antibacterial effects than those prepared by the conventional chemical reduction method. PGA/Alg/AgNP composite microspheres were then prepared with the AgNPs by an emulsion internal gelation method. Such microspheres were found to be a porous and hollow network with pH-sensitive swelling properties and excellent hemostatic performance, indicating its application potentials as an advanced antibacterial hemostatic material.
研究领域:
材料科学
·
纳米技术
·
生物医学工程
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产品关联
DOI
PubMed
高影响因子
ELECTROCHIMICA ACTA
·
2022
·
IF 7.336
Ming-Jia Guo,Cheng-Cheng Xiang,Yi-Yang Hu,Li Deng,Si-Yu Pan,Chao Lv,Shou-Xiao Chen,Hao-Tian Deng,Cheng-Dong Sun,Jun-Tao Li,Yao Zhou,Shi-Gang Sun
Silicon (Si) is considered to be one of the most suitable anode materials for high energy density lithium-ion batteries due to its high theoretical specific capacity. However, the practical application of Si anode is limited by its huge volume change, leading to the rupture of electrode during cycling. In this study, a natural polymer of poly-glutamic acid ( γ -PGA) is derived from nattomycin gum and poly-acrylic acid (PAA) through thermal cross-linking method and served as a dual force cross-linked binder. The two polymers are firmly bonded by dehydration to form the cross-linked γ -PGA-PAA binder with stable ester bonds, which readily creates hydrogen bonding forces with the hydroxyl groups on Si surface. The γ -PGA-PAA exhibits robust mechanical properties to achieve excellent electrochemical performance of Si-based electrode. When the γ -PGA-PAA is used as binder of Si nanoparticle anodes, the capacity retention of Si/ γ -PGA-PAA electrode can reach 63.1% after 300 cycles at charge/discharge current density of 420 mA g −1 with a mass loading of about 0.7 mg cm −2 . As a comparison, the capacity retentions of the Si/PAA and Si/ γ -PGA electrodes are respectively 8.7 and 17.9% under the same conditions. At higher current density of 2940 mA g −1 , the capacity retention of Si/PAA electrode has dropped dramatically to 23.3%, and the Si/ γ -PGA-PAA electrode keeps still high-capacity retention of 72.5% after 400 cycles, while the Si/ γ -PGA electrode can only last 40 cycles. When the three binders are applied to SiO electrode with 1 mg cm −2 loading, the γ-PGA-PAA binder yields also the highest capacity retention of 87.3% after 100 cycles at 160 mA g −1 , while those corresponding to PAA and γ-PGA binders are 81.3% and 74.9%, respectively. XPS characterization results indicate that the γ -PGA-PAA binder has a strong adhesion to Si particles. This cross-linked binder network of γ -PGA-PAA effectively enhances the cycling performance and maintains the structural integrity of Si and SiO electrodes.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2025
·
IF 5.4
Qiuyang Zhang,Ruirui Ma,Kunpeng Jia,Shunhang Dong,Jie Chen,Changjiang Pan
Titanium and its alloys, as the most prevalent materials for orthopedic implants, face two critical challenges in clinical practice: inadequate osseointegration and susceptibility to bacterial infection. To resolve these issues, a multifunctional coating (TNT+XGPP) was developed on Ti implants via three steps: electrochemical anodization to construct TiO 2 nanotube (TNT), hydrothermal loading of bone-affinity Ga 3+ ions (TNT+XG) at different concentrations, and carbodiimide-mediated grafting of γ-polyglutamic acid (γ-PGA) via a polydopamine intermediate layer. The morphology, composition, surface wettability, and ion release behavior of the prepared coatings were thoroughly characterized. The coatings were assessed for early-stage osteoblast growth behavior, Ca-P apatite formation capacity, and antibacterial activity. The characterization results confirmed that Ga 3+ ions and γ-PGA were successfully incorporated into TiO 2 nanotubes, significantly enhancing hydrophilicity. The TNT+XGPP coating, in conjunction with the nanotubes, Ga 3+ ions at appropriate concentrations (5, 20, and 50 mM), and γ-PGA, not only facilitated osteoblast adhesion and proliferation, but also upregulated the expression of osteogenic functional factors (e.g., alkaline phosphatase, osteocalcin, and runt-related transcription factor-2). In contrast, an elevated concentration of Ga 3+ ions (100 mM) in the coating exerted a certain inhibitory effect against osteoblast growth. The TNT+XGPP coating accelerated the in-situ deposition of bone-like Ca-P apatite, attributing to the synergy of γ-PGA and Ga 3+ ions. The released Ga 3+ ions exerted remarkable antibacterial effects against E. coli and S. aureus , with their concentration positively associated with antibacterial activity. This work offers a novel strategy for enhancing the bone affinity and antibacterial properties of Ti-based orthopedic implants.
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DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2023
·Vol. 30
·期 30
·75681-75693
·
IF 5.8
Kang Fei,Lv Qilin,Fan Jingbiao,Zhang Yun,Song Yuling,Ren Xueqin,Hu Shuwen
Soil acidification is a worldwide eco-environmental problem detrimental to plant growth and threatening food security. In this study, calcium poly(aspartic acid) (PASP-Ca) and calcium poly-γ-glutamic acid (γ-PGA-Ca) were obtained through cation exchange and used to mitigate soil acidity owing to high solubility and complexing capability. Three rates at 6.7, 13.4, and 20.1 g kg −1 , denoted as PASP-Ca1, PASP-Ca2, and PASP-Ca3, and γ-PGA-Ca (7.4 g kg −1 ) were surface-applied and compared with conventional lime (CaCO 3 , 2.5 g kg −1 ) along with control in two soil layers (top soil 0–10 cm, subsoil 10–20 cm). After leaching, various soil properties and aluminum fractions were measured to assess their ameliorative performance and mechanisms. Although lime achieved the highest soil pH (6.91) in the topsoil followed by PASP-Ca and γ-PGA-Ca (pH: 5.57–6.33), it had less effect on subsoil increase (5.3) vs. PASP-Ca and γ-PGA-Ca (pH: 5.44–5.74). Surface-applied PASP-Ca demonstrated efficiency in elevating soil pH and reducing exchangeable acidity, mainly as exchangeable Al 3+ , whereas γ-PGA-Ca addition superiorly improved soil pH buffering capacity (pHBC). Moreover, PASP-Ca and γ-PGA-Ca addition improved organic carbon by 34.4–44.9%, available P by 4.80–20.71%, and cation exchange capacity (CEC) by 6.19–29.2%, thus greatly enhanced soil fertility. Ca 2+ from polyAA-Ca promoted the displacement of exchangeable Al 3+ or H + from soil colloid, which were subsequently complexed or protonated and facilitated leaching. Additionally, the transformation into stable organo-aluminum fractions via complexation inhibited further hydrolysis. Under PASP-Ca or γ-PGA-Ca addition, the saturation of aluminum in cation exchange complex was reduced 2.91–7.81% compared to the control without addition amendments. Thus, PASP-Ca and γ-PGA-Ca can serve as potent ameliorants to alleviate soil acidity and aluminum toxicity for sustainable agricultural development.
研究领域:
农业科学
·
环境科学
·
土壤学
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产品关联
DOI
PubMed
高影响因子
Environmental Science-Nano
·
2022
·Vol. 9
·期 8
·2906-2921
·
IF 9.473
Jiachen Huang,Jianquan Luo,Xiangrong Chen,Shichao Feng,Yinhua Wan
Nanofiltration (NF) membranes have been widely applied in wastewater treatment. However, their wider applications and further popularization are still hindered owing to severe membrane fouling and decreasing cleaning efficiency. In this study, Fenton/Fenton-like agents with a strong foulant degradation ability are prepared and selected, and their influence on the physicochemical properties of polyamide (PA) NF membranes and cleaning efficiency are systematically investigated. It is found that the secondary fouling caused by ferric hydroxide precipitates makes the conventional Fenton agent unsuitable for membrane cleaning. Then, a Fenton-like agent with magnetic Fe3O4 nanoparticles modified by γ-poly-glutamic acid (γ-PGA) and L-histidine (L-His) is prepared for membrane cleaning with a low concentration of hydrogen peroxide (<1 mM). Therein, the γ-PGA coating significantly inhibits the agglomeration of nanoparticles by improving their hydrophilicity/dispersibility and reduces their adsorption on the membrane as well as metal ion leaching. More importantly, the imidazole functional groups of L-histidine endow Fe3O4 nanoparticles with a higher affinity for hydrogen peroxide, thus ameliorating their catalytic activity for foulant degradation. Combining alkaline cleaning and Fenton-like catalysis cleaning, the stubborn pore fouling can be almost fully removed (100% and 95% for dead-end and cross-flow filtrations, respectively) because the alkali-induced pore swelling effect would enlarge the membrane pores and enhance the mass transfer of free radicals (˙O2− and ˙OH) into the pores and the release of oxidated foulants. Such a magnetic cleaning agent can be easily recovered and reused for green and sustainable membrane cleaning.
研究领域:
环境科学
·
化学工程
·
材料科学
·
水处理
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DOI
高影响因子
ACS Biomaterials Science & Engineering
·
2019
·
IF 4.511
Jinbiao Gao,Baiqing Yu,Chao Li,Wei Wang,Ming Xu,Zhong Cao,Xiaoyan Xie,Jie Liu
Gene therapy is one of the promising solutions in cancer therapeutics. Ultrasound-mediated gene delivery showed great potential as a noninvasive strategy for gene therapy. However, the efficiency of gene transfection and incorporation of multiple functions remain key challenges in the development of gene delivery systems. In this study, we developed perfluoropentane (PFP) and gold nanorods (AuNRs) loading nanodroplets for photothermal-enhanced ultrasound-mediated imaging and gene transfection. The nanodroplet theranostic system was formulated with fluorinated cationic poly(aspartamide) based polymer that encapsulated PFP, AuNRs, and plasmid DNA and was stabilized with a negatively charged poly(glutamic acid)-g-MeO-poly(ethylene glycol) (PGA-g-mPEG) coating. The nanodroplets presented good stability, biocompatibility, and DNA binding stability. Upon treatment with both near-infrared and ultrasound energy, the photothermal and ultrasound-responsive system exerted a synergistic effect, in which strong adsorption of light induced hyperthermia that promoted the phase transition of PFP and the following ultrasound irradiation, generating strong acoustic cavitation and sonoporation, thus leading to enhanced ultrasound contrast imaging and gene transfection efficiency both in vitro and in vivo.
研究领域:
生物医学工程
·
纳米技术
·
癌症治疗
·
分子生物学
·
医学成像
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产品关联
DOI
PubMed
高影响因子
Biomaterials Science
·
2023
·
IF 6.6
Tingwu Liu,Wen Sun,Xu Zhang,Donghua Xu,Mingzhe Wang,Qiuyan Yan,Jinghua Yin,Shifang Luan
Massive bleeding and wound infection due to severe traumas pose a huge threat to the life and health of sufferers; therefore, it is of clinical importance to fabricate adhesives with rapid hemostatic and superior antibacterial capabilities. However, the weak wet adhesion and insufficient function of existing bioadhesives limits their practical application. In this study, a sandcastle worm protein inspired polyelectrolyte self-coacervate adhesive of poly-γ-glutamic acid (PGA) and lysozyme (LZM) was developed. The adhesive exhibited strong underwater adhesion to various surfaces (>250 kPa for solid plates and >50 kPa for soft tissues) and maintained a 80 kPa even when soaked in water for 7 days. Rat liver and tail defect bleeding models revealed that the hemostatic efficiency was superior to that of commercial samples. The in vitro antimicrobial tests showed that the bacterial inhibition to Staphylococcus aureus and Escherichia coli reached almost 100%. Additionally, the infected wound regeneration model demonstrated that the healing rate of the adhesive group was about 100% within 15 days, which was greater than that of the control group. In vitro and in vivo experiments proved that this facilely prepared adhesive will be a promising material to fulfil the integration functions for rapid wound closure and facilitating wound healing.
研究领域:
材料科学
·
生物医学工程
·
伤口愈合
·
止血
·
抗菌技术
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产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry B
·
2022
·Vol. 10
·期 22
·4261-4273
·
IF 7.571
Hui Guo,Fangzhe Liu,Enqi Liu,Shanshan Wei,Wenbo Sun,Baoqiang Liu,Guoying Sun,Lehui Lu
Micelles as nanocarriers not only offer new opportunities for early diagnosis and treatment of malignant cancers but also encounter numerous barriers in the path of efficient delivery of drugs to diseased areas in the body. To address these issues, we developed a pH/GSH responsive nano-prodrug micelle (NLG919/PGA–Cys–PPA@Gd) with a high drug-loading ratio and controlled drug release performance for MRI-guided tumor photodynamic therapy (PDT) and immune synergistic therapy. Under normal conditions, theranostic nanomicelles remained stable and in a photo-quenched state. Upon accumulation in the tumor site, however, the micelles demonstrated tumor microenvironment (TME) triggered photoactive formed-PPA (a photosensitizer) and NLG919 (an indoleamine 2,3-dioxygenase (IDO) inhibitor) release because the amide bonds of PGA–Cys–PPA and the disulfide linkage of Cys were sensitive to pH and GSH, respectively. More importantly, these micelles could avoid the undesired PPA leakage in blood circulation due to the conjugation between PPA and polymers. Furthermore, the obtained micelles could also enhance the contrast of T1-weighted MRI of tumors by virtue of their high relaxivity (r1 = 29.85 mM−1 s−1). In vitro and in vivo results illustrated that the micelles had good biocompatibility and biosafety. On the basis of the efficient drug delivery strategies in PDT and IDO pathway inhibition, this intelligent dual-drug delivery system could serve as an effective approach for MRI guided combination therapy of cancer.
研究领域:
纳米技术
·
癌症治疗
·
磁共振成像（MRI）
·
药物递送系统
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光动力疗法
·
免疫疗法
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产品关联
DOI
PubMed
高影响因子
EUROPEAN POLYMER JOURNAL
·
2021
·
IF 4.598
Yang Chen,Jie Zhang,Wenhao Xiao,Anfu Chen,Zhixian Dong,Jinbao Xu,Wenhua Xu,Caihong Lei
1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU) was used as organocatalyst to reinvestigate the ring-opening polymerization (ROP) of ε -caprolactone (CL) with benzyl alcohol (BnOH) initiator in bulk at 90 °C considering the unsuccessful ROP of CL at RT in previously reported publications. Kinetic study indicates that the PCLs could be well-designed with a controlled/living character of polymerization. The use of functional initiators, such as 2-hydroxyethyl methacrylate (HEMA), propargyl alcohol (PGA), 6-azido-1-hexanol (AHA) and methoxy poly(ethylene glycol) (mPEG) leads to end-functionalized PCLs. Accordingly, the block copolymerization of CL with δ-valerolactone (VL), trimethylene carbonate (TMC) and lactide (LA) successfully proceeded to give PCL- b -PVL, PCL- b -PTMC and PCL- b -PLA copolymers. Finally, the reaction mechanism was studied with DFT calculations and NMR measurements.
研究领域:
高分子化学
·
材料科学
·
有机化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）