modified polymer
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2021 ◽  
Vol 15 (1) ◽  
pp. 18
Author(s):  
Raphael Mietzner ◽  
Ramona Pawlak ◽  
Ernst R. Tamm ◽  
Achim Goepferich ◽  
Rudolf Fuchshofer ◽  
...  

A root cause for the development and progression of primary open-angle glaucoma might be the loss of the Schlemm’s canal (SC) cell function due to an impaired Angiopoietin-1 (Angpt-1)/Tie2 signaling. Current therapeutic options fail to restore the SC cell function. We propose Angpt-1 mimetic nanoparticles (NPs) that are intended to bind in a multivalent manner to the Tie2 receptor for successful receptor activation. To this end, an Angpt-1 mimetic peptide was coupled to a poly(ethylene glycol)-poly(lactic acid) (PEG-PLA) block co-polymer. The modified polymer allowed for the fabrication of Angpt-1 mimetic NPs with a narrow size distribution (polydispersity index < 0.2) and the size of the NPs ranging from about 120 nm (100% ligand density) to about 100 nm (5% ligand density). NP interaction with endothelial cells (HUVECs, EA.hy926) as surrogate for SC cells and fibroblasts as control was investigated by flow cytometry and confocal microscopy. The NP–cell interaction strongly depended on the ligand density and size of NPs. The cellular response to the NPs was investigated by a Ca2+ mobilization assay as well as by a real-time RT-PCR and Western blot analysis of endothelial nitric oxide synthase (eNOS). NPs with a ligand density of 25% opposed VEGF-induced Ca2+ influx in HUVECs significantly which could possibly increase cell relaxation and thus aqueous humor drainage, whereas the expression and synthesis of eNOS was not significantly altered. Therefore, we suggest Angpt-1 mimetic NPs as a first step towards a causative therapy to recover the loss of SC cell function during glaucoma.


2021 ◽  
Author(s):  
Zhenggong Wang ◽  
Xiaofan Luo ◽  
Kuan Lu ◽  
Shouwen Zhu ◽  
Yanshao Yang ◽  
...  

Abstract Trade-off between permeability and nanometer-level selectivity is an inherent shortcoming of membrane-based separation of molecules, while most highly porous materials with high adsorption capacity lack solution processability and stability for achieving adsorption-based molecule separation. We hereby report a hydrophilic amidoxime modified polymer of intrinsic microporosity (AOPIM-1) as a membrane adsorption material to selectively adsorb and separate small organic molecules from water with ultrahigh processing capacity. The membrane adsorption capacity for Rhodamine B reaches 26.114 g m−2, 10~1000 times higher than previously reported adsorptive membranes. Meanwhile, the membrane achieves >99.9% removal of various nano-sized organic molecules with water flux 2 orders of magnitude higher than typical pressure-driven membranes of similar rejections. This work confirms the feasibility of microporous polymers for membrane adsorption with unprecedented capacity, and provides the possibility of adsorptive membranes for molecular separation.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Soheila Naderi ◽  
Akbar Esmaeili

AbstractExtract oils from plants used in 3D polysaccharides modified with natural protein polymer modified polymer scaffolds can help to reduce blood pressure. This study aimed to use extract oils from plant (EOP)as blood pressure-reducing, bind them to magnetic iron nanoparticles (Fe3O4@NPs), then bind them to polymeric 3D print scaffolds [chitosan, polylactic acid, and polyurethane (CS/PLA/PU), modified with natural protein and finally separate them. This method made it possible to investigate different variables for nanoparticles. In this project, synthesis polymer, modified gelatin (Mo-Ge), PEGylation, extract oils from plant loading and release process in nanocarrier with different concentrations were examined and cell proliferation was optimized. The results show that 75% of the extract oils from plant loaded on iron magnetic nanoparticles containing PEGylated polymer scaffolds was released. Cell proliferation was performed for the sample. In this process, modification of scaffolding with polysaccharides modified with natural protein and extract oils from plant increased the efficiency of nanoparticles among the studied Allium sativum and Zingiber officinale. The size of A. sativum and Z. officinale were 29.833 nm and 150.02 nm size, respectively. These behaved very similarly to each other and A. sativum had the biggest effect in lowering blood pressure. The application of extract oils from plant in 3D mode scaffolding has not been studied before and this is the first analysis to do so, using nanoparticles.


2021 ◽  
pp. 139-174
Author(s):  
Yuliia Onyshchenko ◽  
Ke Vin Chan ◽  
Nathalie De Geyter ◽  
Rino Morent

2021 ◽  
Vol 2097 (1) ◽  
pp. 012004
Author(s):  
Rui Guo ◽  
Siwei Liu ◽  
Zhenhong Liao ◽  
Ren Liu

Abstract This study is focused on the flotation of a cooper mineral.Chrysocolla is poor flotability, surface porous, high porosity, nonuniform property, so it has strong hydrophilic and difficult dissolution. XRD and SEM were used to detect the properties and surface morphology of chrysocolla. The paper make an experiment, it contain modified polymer adsorption - intermediate metal copper ion connection - collector adsorption testing program. The experiment can exchange mineral surface property which enhancing mineral flotation and hydrophobicity. With the conclusion, the results have a trend that increasing the agents can increase mineral recovery, then mineral recovery reach the stable trend. In the simulation of RSM, mineral recovery is based on 3 factors ammonium, xanthate and agent, those factors interact with each other, simulation find the main factor is agent. RSM response surface method has the function of optimizing test results, improving test efficiency, inputting test influence factors and results, and getting the best test factors and results through test simulation.


2021 ◽  
Vol 906 (1) ◽  
pp. 012033
Author(s):  
Aleksandra Rybak ◽  
Aurelia Rybak ◽  
Jaroslaw Joostberens

Abstract Clean coal technologies (CCT) are all technological solutions that are designed to increase the efficiency of coal combustion, processing and extraction. They are therefore, all the technologies that will help to reduce its environmental nuisance during the production and use of coal and can be introduced at various stages of coal application. Earlier was stated that none of the energy sources (natural gas, crude oil and renewable energy sources), their native resources, the used technologies and the sources of imports are not able to eliminate hard coal from the energy mix of Poland in the near future. That is why the authors began research to create a new clean-coal technology based on the hybrid inorganic-organic membranes, which can be used for elimination of harmful substances generated during coal combustion, especially CO2. This work concerns the study of the inorganic-organic hybrid membranes based on few modified polymer matrices and various inorganic fillers. It was found that incorporation of zeolite 4A into the polymer matrix had significantly changed the gas transport parameters (D, P, S and α). In turn, the mechanical (Rm and E) parameters have increased with the filler content. The application allows the initial selection of ingredients from which the final membrane will be created. The designed technology does not require high financial expenditures, and it is also highly universal. It can be used both in households, heating plants and, above all, in power plants.


ACS Omega ◽  
2021 ◽  
Author(s):  
Tanyaradzwa S. Muzata ◽  
Amanuel Gebrekrstos ◽  
Suprakas Sinha Ray

Author(s):  
Tobias G. Brevé ◽  
Huanhuan Liu ◽  
Antonia G. Denkova ◽  
Rienk Eelkema

Coatings ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1275
Author(s):  
Izabela Betlej ◽  
Renata Salerno-Kochan ◽  
Agnieszka Jankowska ◽  
Krzysztof Krajewski ◽  
Jacek Wilkowski ◽  
...  

This study investigated the effect of the homogenization of bacterial cellulose particles and their reintegration into a membrane on the mechanical and physical parameters of the films produced from them in relation to films made of native cellulose (not subjected to the homogenization process). Bacterial cellulose was obtained from a culture of microorganisms forming a conglomerate of bacteria and yeast, called SCOBY. The research has shown that the mechanical modification of bacterial cellulose contributes to an increase in the elongation of the material. Modified polymer films were characterized by a higher Young’s modulus and a much higher breaking force value compared to native cellulose. The mechanical modification of cellulose contributed to an increase in hygroscopicity and changes in water vapor permeability. The obtained results may provide significant information on the methods of modifying bacterial cellulose, depending on its various applications.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Fatemeh Maleki ◽  
Mobina Gholami ◽  
Rezvan Torkaman ◽  
Meisam Torab-Mostaedi ◽  
Mehdi Asadollahzadeh

AbstractNowadays, radiation grafting polymer adsorbents have been widely developed due to their advantages, such as low operating cost, high efficiency. In this research, glycidyl methacrylate monomers were grafted on polypropylene polymer fibers by simultaneous irradiation of gamma-ray with a dose of 20 kGy. The grafted polymer was then modified using different amino groups and tested for adsorption of cobalt ions in an aqueous solution. Finally, the modified polymer adsorbent with a high efficiency for cobalt ions adsorption was synthesized and tested. Different modes of cobalt ions adsorption were tested in other adsorption conditions, including adsorption contact time, pH, different amounts of adsorbent mass, and different concentrations of cobalt ions solution. The adsorbent structure was characterized with FT-IR, XRD, TG and SEM techniques and illustrated having an efficient grafting percentage and adsorption capability for cobalt removing by batch experiments. The optimum conditions were obtained by a central composite design: adsorbent mass = 0.07 g, initial concentration = 40 mg/L, time = 182 min, and pH = 4.5 with ethylenediamine as a modified monomer and high amination percentage. Kinetics and equilibrium isotherms observation described that the experimental data followed pseudo-second-order and Langmuir models, respectively. The maximum adsorption capacity from Langmuir isotherm capacity is obtained equal to 68.02 mg/g.


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