Structure and protein separation efficiency of poly(N-isopropylacrylamide) gels: Effect of synthesis conditions

Kayaman, Nilhan; Kazan, Dilek; Erarslan, Altan; Okay, Oğuz; Baysal, Bahatti̇n M.

doi:10.1002/(sici)1097-4628(19980131)67:5<805::aid-app5>3.0.co;2-x

Cited by 85 publications

(53 citation statements)

References 20 publications

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“…However, as the PNIPAAm hydrogel is heated above LCST, the polymer chains collapse abruptly and phase separation occurs. Such a unique phase transition of the PNIPAAm hydrogel upon external temperature changes has been investigated widely [15].…”

Section: Introductionmentioning

confidence: 99%

Synthesis, rheological behavior and swelling properties of copolymer hydrogels based on poly(N-isopropylacrylamide) with hydrophilic monomers

Seddiki¹,

Aliouche²

2013

Bull. Chem. Soc. Eth.

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ABSTRACT. In this study, hydrogels of poly(N-isopropylacrylamide-co-acrylamide) and poly(Nisopropylacrylamide-co-acrylic acid) having a thermoresponsive character were prepared by aqueous free-radical co-polymerization using the ammonium persulfate/N,N,N', N'-tetramethylethylenediamine (APS/TEMED) redoxpair initiator system in the presence of N,N'-methylenebisacrylamide (MBAAm) crosslinker. (NIPAAm-co-AAm) and (NIPAAm-co-AAc) hydrogels with different thermoresponsive properties were obtained by fixing the initial NIPAAm/AAm mole ratio and and (NIPAAm-co-AAc) mole ratio to 80/20 and changing the crosslinker concentration. The copolymers were characterized with infrared spectroscopy (IR) and differential scanning calorimetry (DSC) techniques. The swelling response of the copolymers networks as a function of time, temperature and swelling environment has been observed to be dependent on both structural aspects of the polymers and swelling environment. The swelling has been observed to be decrease with increase in MBAAm in the copolypolymers networks. Rheological behavior was studies in oscillatory module. All copolymers have a viscoelastic behaviour. We note that the elastic modulus G' increases with increasing hydrophilic monomers.

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Section: Introductionmentioning

confidence: 99%

Synthesis, rheological behavior and swelling properties of copolymer hydrogels based on poly(N-isopropylacrylamide) with hydrophilic monomers

Seddiki¹,

Aliouche²

2013

Bull. Chem. Soc. Eth.

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“…Chemical cross-linking seems to be a more suitable method for the purpose of this study, although it could be toxic to the bacteria. The most commonly used free radical initiator consists of N,N,NЈ,NЈ-tetramethylethylenediamine (TEMED) and peroxodisulfate (potassium or ammonium salt) (15,(43)(44)(45)(46)(47) and works by polymerization of the methacrylate groups (48). However, TEMED is toxic to microbes and was not considered in this work (49).…”

Section: Resultsmentioning

confidence: 99%

Engineering of bio-hybrid materials by electrospinning polymer-microbe fibers

Liu

Rafailovich

Malal

et al. 2009

Proc. Natl. Acad. Sci. U.S.A.

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Although microbes have been used in industrial and niche applications for several decades, successful immobilization of microbes while maintaining their usefulness for any desired application has been elusive. Such a functionally bioactive system has distinct advantages over conventional batch and continuous-flow microbial reactor systems that are used in various biotechnological processes. This article describes the use of polyethylene oxide 99-polypropylene oxide 67-polyethylene oxide99 triblock polymer fibers, created via electrospinning, to encapsulate microbes of 3 industrially relevant genera, namely, Pseudomonas, Zymomonas, and Escherichia. The presence of bacteria inside the fibers was confirmed by fluorescence microscopy and SEM. Although the electrospinning process typically uses harsh organic solvents and extreme conditions that generally are harmful to bacteria, we describe techniques that overcome these limitations. The encapsulated microbes were viable for several months, and their metabolic activity was not affected by immobilization; thus they could be used in various applications. Furthermore, we have engineered a microbe-encapsulated cross-linked fibrous polymeric material that is insoluble. Also, the microbe-encapsulated active matrix permits efficient exchange of nutrients and metabolic products between the microorganism and the environment. The present results demonstrate the potential of the electrospinning technique for the encapsulation and immobilization of bacteria in the form of a synthetic biofilm, while retaining their metabolic activity. This study has wide-ranging implications in the engineering and use of novel bio-hybrid materials or biological thin-film catalysts.biofilm ͉ cross-linking ͉ immobilization ͉ microbial ͉ Zymomonas

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“…Nonporous cylindrical PNIPA gels (PNIPA-2) were prepared by the copolymerization of NIPA with 0.5 mol % of MBAA in Teflon tubes (internal diameter: 6 mm) at a temperature below 5 C according to Kayaman's paper. 17 Porous spherical PNIPA gel (PNIPA-3) containing 2 mol % MBAA prepared by sedimentation polymerization was used.…”

Section: Methodsmentioning

confidence: 99%

Synthesis and Swelling/De-swelling Behavior of Core-Shell Type Gel Consisting of Two Different Poly(N-alkylacrylamide) Gel Layers

Iizawa

Terao

Ohuchida

et al. 2007

Polym J

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ABSTRACT:When poly(acrylic acid) gel-1,8-diazabicyclo-[5,4,0]-7-undecene salt (DAA) was placed in N-methyl-2-pyrrolidone containing an excess of alkylamine and triphenylphosphine, selective amidation occurred from the surface to give the corresponding DAA-poly(N-alkylacrylamide) (PNAA) core-shell type gel, consisting of an unreacted DAA core and a quantitatively amidated shell layer. Further amidation of the DAA-PNAA core-shell type gel with a second alkylamine afforded a novel core-shell type gel consisting of two PNAA layers: PNAA(2) and PNAA(1). Thermal properties of the resulting core-shell type gels, such as swelling/de-swelling behavior, were measured in water at various temperatures. The resulting cylindrical PNAA(2)-PNAA(1) core-shell type gels were resistant to marked deformation caused by swelling/de-swelling because of their axial symmetry. In contrast, the semi-cylindrical double-layer gel prepared from the cylindrical poly(N-isopropylacrylamide)-poly(N-n-propylacrylamide) core-shell type gel was markedly bent in water at temperatures between the lower critical solution temperatures of both layers.

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Structure and protein separation efficiency of poly(N-isopropylacrylamide) gels: Effect of synthesis conditions

Cited by 85 publications

References 20 publications

Synthesis, rheological behavior and swelling properties of copolymer hydrogels based on poly(N-isopropylacrylamide) with hydrophilic monomers

Synthesis, rheological behavior and swelling properties of copolymer hydrogels based on poly(N-isopropylacrylamide) with hydrophilic monomers

Engineering of bio-hybrid materials by electrospinning polymer-microbe fibers

Synthesis and Swelling/De-swelling Behavior of Core-Shell Type Gel Consisting of Two Different Poly(N-alkylacrylamide) Gel Layers

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