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A polymeric platform for immunodiagnostic bioassay was constructed based on biostable polymeric support and two functional monomers, low-fouling methacryloyloxyethyl phosphorylcholine (MPC) and acrylic acid (AAc), by a photografting polymerization approach. Covalent binding of antibody to pAAc chains was achieved by activating carboxyl with NHS/EDC partner. The resultant surface showed obvious suppression of nonspecific protein adsorption and platelet adhesion relative to the control sample, exhibiting good anti-bioadhesion performances. Based on the polymer-supported matrix, a highly sensitive antibody-antigen specific recognition was confirmed in both native plasma and diluted human plasma due to the enhanced antibody loading capacity and lowered bioadhesion as compared to the reference., (Copyright © 2013 Elsevier B.V. All rights reserved.)

The development of technologies for a biomedical detection platform is critical to meet the global challenges of various disease diagnoses. In this study, an inert cycloolefin polymer (COP) support was modified with two-layer polymer brushes possessing dual functions, i.e., a low fouling poly[poly(ethylene glycol) methacrylate] [p(PEGMA)] bottom layer and a poly(acrylic acid) (PAA) upper layer for antibody loading, via a surface-initiated photoiniferter-mediated polymerization strategy for fluorescence-based immunoassay. It was demonstrated through a confocal laser scanner that, for the as-prepared COP-g-PEG-b-PAA-IgG supports, nonspecific protein adsorption was suppressed, and the resistance to nonspecific protein interference on antigen recognition was significantly improved, relative to the COP-g-PAA-IgG references. This strategy for surface modification of a polymeric platform is also applicable to the fabrication of other biosensors.

Biomaterial-associated infections critically compromise the functionality and performance of the medical devices, and pose a serious threat to human healthcare. Recently, natural DNase enzyme has been recognized as a potent material to prevent bacterial adhesion and biofilm formation. However, the vulnerability of DNase dramatically limits its long-term performance in antibacterial applications. In this work, DNase-mimicking polymer brushes were constructed to mimic the DNA-cleavage activity as well as the macromolecular scaffold of the natural DNase. The bacteria repellent efficacy of DNase-mimicking polymer brush-functionalized surface was comparable to that of the DNase-functionalized surface. More importantly, due to their inherent stability, DNase-mimicking polymer brushes presented the much better performance in inhibiting bacterial biofilm development for prolonged periods of time, as compared to the natural DNase. The as-developed DNase-mimicking polymer brush-functionalized surface presents a promising approach to combat biomaterial-associated infections. [ABSTRACT FROM AUTHOR]

Abstract: Hyaluronic acid (HA) is an important component of extracellular matrix (ECM) in many tissues, providing a hemocompatible and supportive environment for cell growth. In this study, glycidyl methacrylate-hyaluronic acid (GMHA) was first synthesized and verified by proton nuclear magnetic resonance (1H NMR) spectroscopy. GMHA was then grafted to the surface of biomedical elastomer poly (styrene-b-(ethylene-co-butylene)-b-styrene) (SEBS) via an UV-initiated polymerization, monitored by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). The further improvement of biocompatibility of the GMHA-modified SEBS films was assessed by platelet adhesion experiments and in vitro response of murine osteoblastic cell line MC-3T3-E1 with the virgin SEBS surface as the reference. It showed that the surface modification with HA strongly resisted platelet adhesion whereas improved cell–substrate interactions. [Copyright &y& Elsevier]

Abstract: In this work, in order to enhance the grafting degree, N-vinyl pyrrolidone (NVP) was used to assist the melt grafting of the macromonomer-poly(ethylene glycol) methyl ether methacrylate (PEGM)-which has good hemocompatible property, onto styrene-b-(ethylene-co-butylene)-b-styrene (SEBS) elastomer with free radical initiator. The grafting degree of PEGM with NVP assistance was increased by at least 4-fold to those without NVP. In addition, side reactions such as homopolyerization of the PEGM monomer during the melt grafting process could be largely reduced in the NVP-assisted system. Both the hydrophilicity and hemocompatibility of the PEGM modified SEBS were highly improved. Comparing to virgin SEBS, the amount of fibrinogen adsorption was reduced by up to 75% in the NVP-assisted grafting samples. [Copyright &y& Elsevier]

Abstract: This work described the graft polymerization of a zwitterionic polymer, [3-(methacryloylamino)propyl]-dimethyl(3-sulfopropyl) ammonium hydroxide (MPDSAH), onto polypropylene non-woven fabric (NWF) membrane via O2 plasma pretreatment and UV-irradiated technique. The surfaces of the modified NWF membranes were principally characterized using attenuated total reflectance Fourier transform infrared spectroscopy (FTIR-ATR), X-ray photoelectron spectroscopy (XPS), and static water contact-angle measurement. The wettability was measured by water contact angle and equilibrium water adsorption. It was found that the water contact angles for the membranes decreased from 123° to 17° with increasing grafting density of poly(MPDSAH) from 0 to 349.2μg/cm2, while the equilibrium water adsorption reached a maximum at the grafting density of 120.5μg/cm2. The decreases of protein adsorption and platelet adhesion on the modified membrane revealed the enhancement protein resistance and excellent resistance to platelet adhesion due to the incorporation of zwitterionic poly(MPDSAH). Besides, microfiltration experiments were carried out to test the antifouling properties. Water flux recovery ratio was achieved as high as 90% for the modified membrane with respect to only about 30% for the neat NWF membrane. [Copyright &y& Elsevier]

Abstract: Polypropylene (PP) was modified with 2-hydroxyethyl acrylate (HEA) by solution radical grafting to introduce active hydroxyl groups on polypropylene backbone (PP-g-HEA). Then the biomimic monomer, 2-methacryloyloxyethyl phosphorycholine (MPC), was grafted onto the surface of PP-g-HEA film (PP-g-HEA-g-MPC) by redox graft polymerizations with ceric(IV) ammonium nitrate as an initiator. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) showed that the HEA and MPC were introduced onto PP molecular chains and the copolymer, PP-g-HEA-g-MPC were formed. The water contact angle measurements demonstrated that the final modified PP film exhibited a better hydrophilic surface compared to the neat PP film. The platelets adhesion on the neat PP, PP-g-HEA and PP-g-HEA-g-MPC film was examined by scanning electron microscopy (SEM). It was found that a large number of platelets were adhered and activated on the surface of neat PP and PP-g-HEA films, while the number of platelets on PP-g-HEA-g-MPC surface was decreased remarkably. The result revealed that the introduction of poly(MPC) onto the PP surface improved the hemocompatibility of PP substantially. [Copyright &y& Elsevier]