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In this study, positively charged monomers were grafted onto negatively charged membranes via UV radiation to improve the antifouling/antibiofouling properties of the polymeric membrane and the stability of the modification layer. The surface properties, morphologies, antifouling and antibiofouling properties, and stability of the modified membranes were systematically characterized. Results indicated that the introduction of [2-(methacryloyloxy) ethyl] trimethylammonium chloride (MTAC) monomers onto polyethersulfone (PES)/sulfonated polyethersulfone (SPES) membranes effectively increased the surface hydrophilicity. Meanwhile, the surfaces were neutralized with ~0 mV zeta potential in pH 3-10. Moreover, the formation of a polyampholytic copolymer and the antibacterial ability of MTAC considerably improved the antibiofouling properties of the modified membranes. The MTAC-grafted PES/SPES membranes showed excellent antifouling/antibiofouling properties during the treatment of various types of wastewater, including bovine serum albumin solution, oil/water emulsion, and bacterial suspension. Therefore, this study provides a simple and effective method of constructing stable and antifouling membranes for sustainable water treatment., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

To overcome the organic-/bio- fouling of the membrane, a dual-functional ultrafiltration membrane containing quaternary ammonium and zwitterionic polymers via quaternization and surface radical polymerization was designed, and its antifouling and antibacterial behavior was studied. In this work, poly(vinylidene fluoride)/poly(methyl methacrylate-co-dimethylamino-2-ethyl methacrylate) (PVDF/P(MMA-co-DMAEMA)) blend membrane was quaternized by p-chloromethyl styrene (p-CMS), and the double bonds were introduced onto the membrane surface, which further participated in the polymerization of zwitterionic monomers on the membrane surface. The results indicated that the resultant membrane exhibited obviously improved hydrophilicity and weak positive charge (isoelectric point, 7.49). The membrane presented higher flux recovery ratio and lower protein adhesion compared with the pure PVDF membrane. Meanwhile, the membrane showed high-efficiency broad-spectrum antibacterial performance, that is, the bacteria killing efficiency of S. aureus and E. coli reached 98.2% and 97.0%, respectively. Moreover, the membrane effectively inhibited bacterial adhesion, which is important for the long-term antibacterial properties of membrane. This antifouling and antibacterial PVDF membrane may have potential in the long-term filtration process, especially when dealing with microbiologically contaminated water., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

To improve the permeability and antifouling properties of polyvinyl chloride (PVC) ultrafiltration (UF) membrane, amphiphilic sulfonated polysulfone (SPSF) was introduced into PVC matrix. Three types of PVC/SPSF blend membranes containing different SPSF with the sulfonation degree (SD) of 20%, 30%, and 50% were fabricated by non-solvent induced phase separation (NIPS) process. The excellent compatibility between PVC and SPSF was confirmed by differential scanning calorimetry (DSC). Surface chemical compositions, morphology, roughness, charge, hydrophilicity, permeability and antifouling properties of the pristine PVC membrane and the PVC/SPSF blend membranes were systematically compared and characterized. Due to the improved hydrophilicity and endowed negative charge, the blend membrane showed high water permeability (i.e. 880 L m -2 h -1 bar -1 ), high bovine serum albumin (BSA) rejection (i.e. 95.7%), and high flux recovery ratio (i.e. 96%), which outperformed ever reported and commercialized PVC membranes. Furthermore, the permeability and rejection properties of PVC/SPSF UF membranes were maintained after soaking in acidic and alkaline solutions for 30 days, indicating their outstanding acid and alkali tolerance. Therefore, SPSF was expected as a potential versatile modifier for fabricating high performance UF membranes., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

To enhance hexavalent chromium (Cr(VI)) removal performance under acidic conditions, the nanofiltration (NF) membrane with enhanced negative charge was fabricated via introducing 2, 5-diaminobenzenesulfonic acid (DABSA) into polyamide layer. The control membrane (NF-P) was directly prepared from piperazine and 1, 3, 5-benzenetricarbonyltrichloride. Surface chemical compositions, morphology, surface charge, pore size, permeability and pH-dependent separation performance of the fabricated membranes were characterized. The membranes showed the similar water permeance (∼11.5 L m -2  h -1  bar -1 ) and Na 2 SO 4 rejections (∼98%) under neutral environments. The DABSA introduced NF membrane (NF-PD) was negatively charged in the pH range of 2.5-11, while the isoelectric point for NF-P was ∼pH 4.0. Cr(VI) removal ability was then evaluated under various concentrations and pH environments. The results indicated that NF-PD showed the better Cr(VI) rejection performance in all tested conditions than NF-P, especially under acidic environments (e.g., pH 4 and pH 5). Moreover, there was a fluctuation of the rejection with the increase of Cr(VI) concentration under acidic environments, which was mainly caused by the formation of Cr 2 O 7 2- species. The harmful Cr(VI) was efficiently removed by the NF membrane with enhanced negative charge under acidic environments, which indicated the wider application range of the NF membrane., (Copyright © 2019 Elsevier Inc. All rights reserved.)

We demonstrate the preparation and properties of poly(vinylidene fluoride) (PVDF) filtration membranes modified via surface zwitterionicalization mediated by reactive core-shell silica nanoparticles (SiO2 NPs). The organic/inorganic hybrid SiO2 NPs grafted with poly(methyl meth acrylate)-block-poly(2-dimethylaminoethyl methacrylate) copolymer (PMMA-b-PDMAEMA) shell were prepared by surface-initiated reversible addition fragmentation chain transfer (SI-RAFT) polymerization and then used as a membrane-making additive of PVDF membranes. The PDMAEMA exposed on membrane surface and pore walls were quaternized into zwitterionic poly(sulfobetaine methacrylate) (PSBMA) using 1,3-propane sultone (1,3-PS) as the quaternization agent. The membrane surface chemistry and morphology were analyzed by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM), respectively. The hydrophilicity, permeability and antifouling ability of the investigated membranes were evaluated in detail. It was found that the PSBMA chains brought highly-hydrophilic and strong fouling resistant characteristics to PVDF membranes due to the powerful hydration of zwitterionic surface. The SiO2 cores and PMMA chains in the hybrid NPs play a role of anchors for the linking of PSBMA chains to membrane surface. Compared to the traditional strategies for membrane hydrophilic modification, the developed method in this work combined the advantages of both blending and surface reaction., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Signal regulatory protein (SIRP) α, a transmembrane protein belonging to the immunoglobulin superfamily, is a receptor for CD47. The interaction between SIRPα and CD47 plays an important role in regulating the phagocytosis of leukemia cells and leukemia stem cells (LSCs) by macrophages. Blocking antibodies against CD47 have been shown to promote phagocytosis of LSCs by macrophages. Here, we consider an alternative way to interrupt the interaction between CD47 and SIRPα. We expressed the extracellular domains of the human SIRPα (hSIRP(ext)) and the human CD47 (hCD47(ext)) in Escherichia coli as Trx fusion proteins, and purified them by using affinity chromatography. We show that the purified fusion protein Trx-SIRP(ext) could interact in vitro with Trx-hCD47(ext). Moreover, Trx-SIRP(ext) could effectively bind to Jurkat T-ALL cells, which expressed CD47 at a high level. CD47(ext), on the other hand, bound to human macrophages. In vitro phagocytosis assay showed that these fusion proteins could enhance the phagocytosis of Jurkat cells by macrophage, with Trx-hSIRP(ext) showed a higher efficiency than Trx-CD47(ext). These results indicated that the soluble Trx-hSIRP(ext) and Trx-CD47(ext) polypeptides could be alternative molecules to interrupt CD47-SIRPα interaction between leukemia cells and macrophages, and might be potentially useful for the targeted therapy of leukemia., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Superhydrophilic organic/inorganic hybrid surfaces have been fabricated on blend membranes of poly(vinylidene fluoride) (PVDF) and poly(styrene-alt-maleic anhydride) (SMA). The blend membranes were prepared from PVDF/SMA mixed solution with N,N-dimethylacetamide (DMAc) as solvent by immersion-precipitation phase inversion process. The gained blend membranes were immersed into γ-aminopropyltriethoxysilane (APTS) solution to generate SMA/silica hybrid surfaces by the reaction between anhydrides and APTS. The hybrid surfaces chemical compositions, morphologies and hydrophilicity were investigated in detail. It demonstrates that the hybrid surfaces possess micro-nano hierarchical structure and display superhydrophilicity property and good stability. Finally, the reaction and formation mechanism of the superhydrophilicity hybrid surface was discussed., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Chinese mitten crab Eriocheir sinensis is one of the most important aquaculture crustacean species in China. A cDNA library was constructed from mixed tissues of E. sinensis challenged with LPS. Eight genes involved in immune response were identified from 319 single colonies. Among them, two different C-type lectin-like domain (CTLD)-containing proteins were firstly identified in Chinese mitten crab. The full-length cDNA sequences of two C-type lectin-like domain (CTLD)-containing proteins named EsCTLDcp-1 and EsCTLDcp-2 were cloned by 5' RACE. The deduced amino acid sequences of EsCTLDcp-1 and EsCTLDcp-2 possessed several conserved features of C-type lectin subfamily. The tissue distribution of EsCTLDcp-1 and EsCTLDcp-2 was examined by Real-time PCR. In the normal Chinese mitten crab, the expression of EsCTLDcp-2 was detected in all tested tissues such as haemolymph, muscle, intestine, gill, heart, gonad and hepatopancreas, whereas in muscle, intestine, gill, heart and hepatopancreas for EsCTLDcp-1. The highest expressions of EsCTLDcp-1 and EsCTLDcp-2 were both observed in hepatopancreas. LPS significantly induced the expression of EsCTLDcp-1 and EsCTLDcp-2 in the hepatopancreas at the different time points. The induced fold change of EsCTLDcp-1 and EsCTLDcp-2 increased significantly from 2 h for EsCTLDcp-1 and 4 h for EsCTLDcp-2, and reached a maximum at 12 h, then dropped at 24 h. A differential pattern was found in Chinese mitten crab challenged with Chinese mitten crab pathogen Aeromonas hydrophila. The expression of EsCTLDcp-1 increased significantly at 2 h post-challenge crabs with A. hydrophila, then decreased at 4 h and 8 h, after that increased at 12 h and 24 h. The expression of EsCTLDcp-2 was decreased at the all time points. All these data suggest a differential role of EsCTLDcp-1 and EsCTLDcp-2 in the crab innate immune response to bacterial infection., (Copyright © 2010 Elsevier Ltd. All rights reserved.)