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polymeric nanoparticles developed by vitamin E-modified aliphatic polycarbonate polymer to promote oral absorption of oleanolic acid

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Asian Journal of Pharmaceutical Sciences 2017年第6期12卷 586-593页

作者： Wenjuan Zhang Chufan Liang Hao Liu Zhenbao Li Rui Chen Mei Zhou Dan Li Qing Ye Cong Luo Jin Sun School of Pharmacy Shenyang Pharmaceutical UniversityNo.103Wenhua RoadShenyang 110016China HAISCO(Shenyang)Pharmaceutical Co.Ltd. ShenyangChina School of Pharmacy BioMolecular Sciences DepartmentThe University of MississippiOxfordMS 38677USA School of Continuing Education Shenyang Pharmaceutical UniversityNo.103Wenhua RoadShenyang 110016China Municipal Key Laboratory of Biopharmaceutics School of PharmacyShenyang Pharmaceutical UniversityNo.103Wenhua RoadShenyang 110016China

Oleanolic acid (OA) exhibited good pharmacological activities in the clinical treatment of hypoglycemia, immune regulation, acute jaundice and chronic toxic hepatitis. However, the oral delivery of OA is greatly limited by its inferior water solubility and poor intestinal mucosa permeability. Herein, we developed a novel polymeric nanoparticle (NP) delivery system based on vitamin E modified aliphatic polycarbonate (mPEG-PCC-VE) to facilitate oral absorption of OA. OA encapsulated mPEG-PCC-VE NPs (OA/mPEG-PCC-VE NPs) showed uniform particle size of about 170 nm with high drug loading capability (8.9%). Furthermore, the polymeric mPEG-PCC-VE NPs, with good colloidal stability and pH-sensitive drug release characteristics, significantly enhanced the in vitro dissolution of OA in the alkaline medium. The in situ single pass intestinal perfusion (SPIP) studies performed on rats demonstrated that the OA/m PEG-PCC-VE NPs showed significantly improved permeability in the whole intestinal tract when compared to OA solution, especially for duodenum and colon. As a result, the in vivo pharmacokinetics study indicated that the bioavailability of OA/m PEG-PCC-VE NPs showed 1.5-fold higher than commercially available OA tablets. These results suggest that mPEGPCC-VE NPs are a promising platform to facilitate the oral delivery of OA.

关键词： Oleanolic acid polymeric nanoparticles mPEG-PCC-VE Oral delivery

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Characterization of changes in extracellular polymeric substances and heavy metal speciation of waste activated sludge during typical oxidation solubilization processes

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Journal of Environmental Sciences 2019年第6期31卷 146-158页

作者： Qiongying Xu Huidi Wang Qiandi Wang Weijun Zhang Dongsheng Wang Faculty of Materials Science and Chemistry China University of Geosciences School of Environmental Studies China University of Geosciences Hubei Provincial Engineering Research Center of Systematic Water Pollution Control State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Biopolymer solubilization is considered to be the rate-limiting stage of anaerobic digestion of waste activated sludge(WAS). Oxidation processes have been proven to be effective in disrupting sludge flocs and causing solubilization of the solid biopolymers. In this study,WAS was treated by NaNO2 or H2 O2 oxidation at p H of 2. The changes in extracellular polymeric substances properties and the speciation of heavy metals were investigated. The results revealed that both NaNO2 and H2 O2 treatments were effective in solubilizing organics in WAS, while the conversion of biopolymers in the two treatment processes was different. Free nitrous acid destroyed the gel network structure of EPS, and organic materials were released from the solid phase to the supernatant. Indigenous peroxidase catalyzed H2 O2 to produce hydroxyl radicals which caused significant solubilization of biopolymers, and the protein-like substances were further degraded into micro-molecule polypeptides or amino acids at high dosages of H2 O2. During the oxidation processes, Zn, Cd and Cu, with excellent mobility, tended to migrate to the supernatant, and thus were easy to remove through the liquid–solid separation process. Ni and As showed moderate migration ability, of which the residual fraction tended to transform into reducible and soluble fractions. With poor mobility, Cr and Pb mainly existed in the forms of residual and oxidizable fractions, which were difficult to dissolve and remove from WAS. Both NaNO2 and H2 O2 treatment resulted in the enhancement of sludge solubilization efficiency and heavy metal mobility in WAS, but different heavy metals showed distinct migration and transformation behaviors.

关键词： Extracellular polymeric substances(EPS) Oxidation Biopolymers solubilization Biodegradability Heavy metals

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Emerging polymeric biomaterials and manufacturing techniques in regenerative medicine

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Aggregate 2022年第5期3卷 59-81页

作者： Dan Xia Jiatian Chen Zhongyang Zhang Mingdong Dong Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology School of Materials Science and EngineeringHebei University of TechnologyTianjinChina Interdisciplinary Nanoscience Center(iNANO) Aarhus UniversityAarhusDenmark

The current demand for patients’organ and tissue repair and regeneration is continually increasing,where autologous or allograft is the golden standard treatment in the clinic.However,due to the shortage of donors,mismatched size and modality,functional loss of the donor region,possible immune rejection,and so forth,the application of auto-/allo-grafts is frequently hindered in many cases.In order to solve these problems,artificial constructs structurally and functionally imitating the extracellular matrix have been developed as substitutes to promoting cell attachment,proliferation,and differentiation,and ultimately forming functional tissues or organs for better tissue regeneration.Particularly,polymeric materials have been widely utilized in regenerative medicine because of their ease of manufacturing,flexibility,biocompatibility,as well as good mechanical,chemical,and thermal properties.This review presents a comprehensive overview of a variety of polymeric materials,their fabrication methods as well applications in regenerative medicine.Finally,we discussed the future challenges and perspectives in the development and clinical transformation of polymeric biomaterials.

关键词： polymeric biomaterials utilized

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polymeric nanoparticles of poly(2-oxazoline),tannic acid and doxorubicin for controlled release and cancer treatment

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Chinese Chemical Letters 2020年第2期31卷 501-504页

作者： Lin Liu Liying Yin Hang Bian Ning Zhang Department of Chemistry Northeast Normal UniversityChangchun 130024China School of Material Science and Engineering Jilin Jianzhu UniversityChangchun 130118China

A straightforward coassembly strategy was developed for the preparation of polymeric nanoparticles driving by the intermolecular hydrogen bond between neutral poly(2-methyl-2-oxaozline)(PMeOx),tannic acid(TA) and doxorubicin hydrochloride(Dox).The occurrence of the hydrogen-bonding amongst the different functionalities within the formed nanoparticles was verified by infrared(IR) spectroscopy.Scanning electron microscopy(SEM),dynamic light scattering(DLS),UV-vis absorption and photoluminescent measurements indicated the rapid formation of uniform and water dispersible/stable nanoparticles.The relative poor stability of PMeOx-TA-Dox in fetal bovine serum(FBS) solution enabled the rapid separation of Dox and PMeOx-TA,facilitating the release of Dox and its entrance into cellular nuclei as revealed by confocal laser scanning microscopy(CLSM).The presented strategy may provide an efficient alternative for the construction of multifunctional nanomedicines.

关键词： polymeric nanoparticle Poly(2-oxazoline) Drug delivery Self-assembly Doxorubicin

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Use of polymeric sub-micron ion-exchange resins for removal of lead,copper,zinc,and nickel from natural waters

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Journal of Environmental Sciences 2019年第1期31卷 247-254页

作者： Audrey Murray Banu ?rmeci Department of Civil and Environmental Engineering Carleton University

This research investigated the removal capacity of polymeric sub-micron ion-exchange resins(SMR) for removal of lead, copper, zinc, and nickel from natural waters in competition with natural organic matter(NOM). polymeric SMR particles were created and tested to ensure that they were adequately dispersed in the solution. They removed little NOM(10%or less) from river water and wastewater, indicating that competition from NOM was not a major concern. SMR were able to remove 82% ± 0.2% of lead, 46% ± 0.6% of copper, 55% ±20% of zinc, and 17% ± 2% of nickel from river water spiked with 500 μg/L of each. Similarly,in wastewater, they were able to remove 86% ± 0.1% of lead, 38% ± 0.8% of copper, 28% ± 1%of zinc, and 11% ± 1% of nickel.

关键词： Water Wastewater Heavy metals Ion exchange polymeric submicron resin Natural organic matter (NOM)

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Porous polymeric Catalysts Constructed from Vinylated Functionalities

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Accounts of Materials Research 2022年第7期3卷 772-781页

作者： Qi Sun Feng-Shou Xiao Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China

CONSPECTUS:Porous organic polymers(POPs)have revolutionized the production of advanced catalytic materials with unique features such as a large surface area,tunable pore structure,ease of functionalization with a wide range of functional groups,and the ability to function as hosts for encapsulation of functional species,making them appealing for task-specific applications.Although numerous POP-based catalysts have been developed,they are rarely used as a common tool for preparatory-scale operations in laboratories.

关键词： Porous operations polymeric

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Synthesis and evaluation of cationic polymeric micelles as carriers of lumbrokinase for targeted thrombolysis

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Asian Journal of Pharmaceutical Sciences 2019年第2期14卷 144-153页

作者： Yang Pan Xiahui Wang Zongning Yin Key Laboratory of Drug Targeting and Drug Delivery Systems West China School of Pharmacy Sichuan University

To achieve targeted thrombolysis, a targeted delivery system of lumbrokinase(LK) was constructed using RGDfk-conjugated hybrid micelles. Based on the specific affinity of RGDfk to glycoprotein complex of GP Ⅱ b/Ⅲ a expressed on the surface of membrane of activated platelet, LK loaded targeted micelles(LKTM) can be delivered to thrombus. The hybrid micelles were composed of polycaprolactone-block-poly(2-(dimethylamino) ethyl methacrylate)(PCL-PDMAEMA), methoxy polyethylene glycol-block-polycaprolactone(mPEG-PCL)and RGDfk conjugated polycaprolactone-block-polyethylene glycol(PCL-PEG-RGDfk). PCLPDMAEMA was synthesized via ring open polymerization(ROP) and atom transfer radical polymerization(ATRP). PCL-PEG-RGDfk was synthesized via ROP and carbodiimide chemistry. The prepared LKTM was characterized by dynamic light scattering(DLS) and transmission electron microscope(TEM). Colloidal stability assay showed the prepared LKTM was stable. Biocompatibility assay was performed to determine the safe concentration range of polymer. The assay of fluorescent distribution in vivo demonstrated that LKTM can be efficiently delivered to thrombi in vivo. Thrombolysis in vivo indicated the thrombolytic potency of LKTM was optimal in all groups. Notably, the laboratory mice treated with LKTM exhibited a significantly shorter tail bleeding time compared to those treated with LK or LK-loaded micelles without RGDfk, which suggested that the targeted delivery of LK using RGDfk-conjugated hybrid micelles effectively reduced the bleeding risk.

关键词： Targeted thrombolysis Lumbrokinase polymeric micelles ATRP ROP

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Grafting polymeric sulfur onto carbon nanotubes as highly-active cathode for lithium–sulfur batteries

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Journal of Energy Chemistry 2020年第3期29卷 27-33页

作者： Junfeng Wu Siyu Ding Shihai Ye Chao Lai Institute of New Energy Material Chemistry School of Materials Science and EngineeringNational Institute for Advanced MaterialsNankai UniversityTianjin 300350China School of Chemistry and Materials Science Jiangsu Normal UniversityXuzhou 221116JiangsuChina

Lithium–sulfur(Li–S)batteries are being explored as promising advanced energy storage systems due to their ultra-high energy density.However,fast capacity fading and low coulombic efficiency,resulting from the dissolution of polysulfides,remain a serious challenge.Compared to weak physical adsorptions or barriers,chemical confinement based on strong chemical interaction is a more effective approach to address the shuttle issue.Herein,we devise a novel polymeric sulfur/carbon nanotube composite for Li–S battery,for which 2,5-dithiobiurea is chosen as the stabilizer of long-chain sulfur.This offers chemical bonds which bridge the polymeric sulfur and carbon nanotubes.The obtained composite can deliver an ultra-high reversible capacity of 1076.2 m Ahg^-1(based on the entire composite)at the rate of 0.1 C with an exceptional initial Coulombic efficiency of 96.2%,as well as remarkable cycle performance.This performance is mainly attributed to the reaction reversibility of the obtained polymeric sulfur-based composite during the discharge/charge process.This was confirmed by density functional theory calculations for the first time.

关键词： Lithium–sulfur batteries polymeric sulfur Carbon nanotubes DFT calculations High capacity

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Insight into the distribution of metallic elements in membrane bioreactor: Influence of operational temperature and role of extracellular polymeric substances

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Journal of Environmental Sciences 2019年第2期31卷 111-120页

作者： He Wang Xiufen Li Xinhua Wang Yueping Ren Laboratory of Environmental Biotechnology School of Environmental and Civil EngineeringJiangnan University Jiangsu Key Laboratory of Anaerobic Biotechnology

The distribution of metallic elements in a submerged membrane bioreactor(MBR) was revealed at different temperatures using inductively coupled plasma-optical emission spectrometry(ICP-OES), and the role of extracellular polymeric substances(EPS) was probed by integrating scanning electron microscopy(SEM) with confocal laser scanning microscopy(CLSM) over long-term operation. More metallic elements in the influent were captured by suspended sludge and built up in the fouling layer at lower temperature. The concentration of metallic elements in the effluent was 5.60 mg/L at 10°C operational temperature, far lower than that in the influent(51.35 mg/L). The total contents of metallic elements in suspended sludge and the membrane fouling layer increased to 40.20 and 52.19 mg/g at 10°C compared to 35.14 and 32.45 mg/g at 30°C, and were dominated by the organically bound fraction. The EPS contents in suspended sludge and membrane fouling layer sharply increased to 37.88 and 101.51 mg/g at 10°C, compared to 16.87 and 30.03 mg/g at 30°C. The increase in EPS content at lower temperature was responsible for the deposition of more metallic ions. The strong bridging between EPS and metallic elements at lower temperature enhanced the compactness of the fouling layer and further decreased membrane flux. This was helpful for understanding the mechanism of membrane fouling at different operational temperatures and the role of EPS, and also of significance for the design of cleaning strategies for fouled membranes after long-term operation.

关键词： Membrane bioreactor Metallic elements Extracellular polymeric substances

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Evaluation of the secondary structures of protein in the extracellular polymeric substances extracted from activated sludge by different methods

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Journal of Environmental Sciences 2019年第6期31卷 128-136页

作者： Benyi Xiao Yu Liu Meng Luo Tang Yang Xuesong Guo Hao Yi Research Center for Eco-Environmental Sciences Chinese Academy of Sciences University of Chinese Academy of Sciences Beijing ZEHO Waterfront Ecological Environment Treatment Company South China Institute of Environmental Sciences Ministry of Environmental Protection

The changes of protein secondary structures in the extracellular polymeric substances(EPS) extracted from activated sludge by four different methods were studied by analyzing the amide I region(1700–1600 cm-1) of the Fourier transform infrared spectra and model protein test. The results showed the molecular weight distribution of organic matter extracted by centrifugation, heating and cation exchange resin(CER) was similar, while the EPS extracted by centrifugation(Control) and CER had similar fluorescent organic matter. The protein secondary structures of extracted EPS by the four methods were different. The similarities of protein secondary structures between the EPS extracted by CER with the Control were the highest among the four extracted EPS. Although the EPS yield extracted by formaldehyde + NaOH method were the highest, its protein secondary structures had the lowest similarity with those extracted by the Control. Additionally, the effects of centrifugation and CER extraction on the secondary structures of bovine serum albumin were also lower than that of other extraction processes. CER enables the second maximum extraction of EPS and maximum retention of the original secondary structure of proteins.

关键词： Activated sludge Different extraction methods Extracellular polymeric substances Protein secondary structure

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