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Preliminary observations of the role of material morphology on protein - electrophoretic transport in gold nanocomposite hydrogels / Jeffery W. Thompson in Industrial & engineering chemistry research, Vol. 49 N° 23 (Décembre 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 23 (Décembre 2010) . - pp. 12104–12110 Titre : Preliminary observations of the role of material morphology on protein - electrophoretic transport in gold nanocomposite hydrogels Type de document : texte imprimé Auteurs : Jeffery W. Thompson, Auteur ; Holly A. Stretz, Auteur ; Pedro E. Arce, Auteur Année de publication : 2011 Article en page(s) : pp. 12104–12110 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Gold  Nanocomposite Résumé : Nanocomposite polymeric hydrogels have potential to play an important role in clinical diagnostics, therapeutic agents, and electroanalytical devices, among other biotechnological applications. However, the relationship between nanocomposite structure (morphology) and transport specifically of proteins has not been systematically described. In this study, polyacrylamide (PAM) nanocomposites have been synthesized containing various compositions and aspect ratios of gold nanoparticles (GNP). These nanocomposite hydrogels have been characterized for morphology, and examined for their ability to change the effective electrophoretic mobility of a model protein, ovum serum albumin (OSA), under a low applied electric field of 6.7 V/cm. Addition of spherical (low aspect ratio) gold nanoparticles reduces the effective mobility of OSA, a result that cannot be explained by the lower effective cross-link density noted in swelling studies. However, the effective mobility of OSA can be predicted using simple tortuous path models, specifically the Lape−Cussler. An increase in aspect ratio of the nanoparticles produced further reductions in mobility, and this reduction was so significant that tortuous path contribution could not explain it. We expect that percolation of the higher aspect ratio gold nanoparticles (as seen in TEM images) led to preferred conduction through the gold network, and therefore resulted in lower mobility in the buffer. The structure−mobility relationships found here help establish one possible regime for transport of proteins through nanocomposite hydrogels. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100291b [article] Preliminary observations of the role of material morphology on protein - electrophoretic transport in gold nanocomposite hydrogels [texte imprimé] / Jeffery W. Thompson, Auteur ; Holly A. Stretz, Auteur ; Pedro E. Arce, Auteur . - 2011 . - pp. 12104–12110. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 23 (Décembre 2010) . - pp. 12104–12110 Mots-clés : Gold  Nanocomposite Résumé : Nanocomposite polymeric hydrogels have potential to play an important role in clinical diagnostics, therapeutic agents, and electroanalytical devices, among other biotechnological applications. However, the relationship between nanocomposite structure (morphology) and transport specifically of proteins has not been systematically described. In this study, polyacrylamide (PAM) nanocomposites have been synthesized containing various compositions and aspect ratios of gold nanoparticles (GNP). These nanocomposite hydrogels have been characterized for morphology, and examined for their ability to change the effective electrophoretic mobility of a model protein, ovum serum albumin (OSA), under a low applied electric field of 6.7 V/cm. Addition of spherical (low aspect ratio) gold nanoparticles reduces the effective mobility of OSA, a result that cannot be explained by the lower effective cross-link density noted in swelling studies. However, the effective mobility of OSA can be predicted using simple tortuous path models, specifically the Lape−Cussler. An increase in aspect ratio of the nanoparticles produced further reductions in mobility, and this reduction was so significant that tortuous path contribution could not explain it. We expect that percolation of the higher aspect ratio gold nanoparticles (as seen in TEM images) led to preferred conduction through the gold network, and therefore resulted in lower mobility in the buffer. The structure−mobility relationships found here help establish one possible regime for transport of proteins through nanocomposite hydrogels. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100291b

Role of nanocomposite hydrogel morphology in the electrophoretic separation of biomolecules / Jyothirmai J. Simhadri in Industrial & engineering chemistry research, Vol. 49 N° 23 (Décembre 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 23 (Décembre 2010) . - pp. 11866–11877 Titre : Role of nanocomposite hydrogel morphology in the electrophoretic separation of biomolecules : a review Type de document : texte imprimé Auteurs : Jyothirmai J. Simhadri, Auteur ; Holly A. Stretz, Auteur ; Mario Oyanader, Auteur Année de publication : 2011 Article en page(s) : pp. 11866–11877 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Nanocomposite  hydrogel  Electrophoretic Résumé : Hydrogels are widely used to produce biomolecular separations in electrophoretic applications, where gel morphology and charge effects combine to produce the separation. Nanocomposite gels are poised to revolutionize this field in both improved handling characteristics and improved separations. Gel morphology and charge effects have traditionally been manipulated by varying the copolymer composition, but recent reports show that novel morphological changes can also be induced in the gel using templating methods and nanoparticle addition. To aid realization of the potential for novel electrically driven separations arising from such novel morphologies, we review here advances in materials development alongside a review of the directions in biomolecule/hydrogel electrophoretic transport modeling. Models for polyelectrolyte transport that are potentially useful for understanding novel behaviors caused by gel morphology are analyzed first. With the perspective of theoretical guidance, we then survey nanocomposite hydrogel morphologies keyed by the nanoparticle and matrix. Finally, we survey as well reports of dramatic improvements in the mechanical properties that may be the key to the early adoption of these new materials in biomolecular separation applications. For modeling, we have identified the different scales involved in biomolecular transport in these materials and provided a taxonomy of transport models that emphasize the role of gel morphology in determining both polyelectrolyte mobility and diffusion. Three aspects for future work unique to nanocomposite gel materials are described: (a) descriptions of the distribution of nanoparticles within the gels; (b) descriptions of the motion of the buffer solution that may include electroosmotic effects for nanoparticles with surface charges; (c) descriptions of the motion of the polyelectrolyte molecule inside the new gel material for a given application. These aspects will help to uncover further quantitative details about the ability of these gels to be tunable for differential mass transport of a given type of molecule. Standard gels, currently, lack a broad flexibility to increase the separation of biomolecules and, in general, are not tunable. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1003762 [article] Role of nanocomposite hydrogel morphology in the electrophoretic separation of biomolecules : a review [texte imprimé] / Jyothirmai J. Simhadri, Auteur ; Holly A. Stretz, Auteur ; Mario Oyanader, Auteur . - 2011 . - pp. 11866–11877. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 23 (Décembre 2010) . - pp. 11866–11877 Mots-clés : Nanocomposite  hydrogel  Electrophoretic Résumé : Hydrogels are widely used to produce biomolecular separations in electrophoretic applications, where gel morphology and charge effects combine to produce the separation. Nanocomposite gels are poised to revolutionize this field in both improved handling characteristics and improved separations. Gel morphology and charge effects have traditionally been manipulated by varying the copolymer composition, but recent reports show that novel morphological changes can also be induced in the gel using templating methods and nanoparticle addition. To aid realization of the potential for novel electrically driven separations arising from such novel morphologies, we review here advances in materials development alongside a review of the directions in biomolecule/hydrogel electrophoretic transport modeling. Models for polyelectrolyte transport that are potentially useful for understanding novel behaviors caused by gel morphology are analyzed first. With the perspective of theoretical guidance, we then survey nanocomposite hydrogel morphologies keyed by the nanoparticle and matrix. Finally, we survey as well reports of dramatic improvements in the mechanical properties that may be the key to the early adoption of these new materials in biomolecular separation applications. For modeling, we have identified the different scales involved in biomolecular transport in these materials and provided a taxonomy of transport models that emphasize the role of gel morphology in determining both polyelectrolyte mobility and diffusion. Three aspects for future work unique to nanocomposite gel materials are described: (a) descriptions of the distribution of nanoparticles within the gels; (b) descriptions of the motion of the buffer solution that may include electroosmotic effects for nanoparticles with surface charges; (c) descriptions of the motion of the polyelectrolyte molecule inside the new gel material for a given application. These aspects will help to uncover further quantitative details about the ability of these gels to be tunable for differential mass transport of a given type of molecule. Standard gels, currently, lack a broad flexibility to increase the separation of biomolecules and, in general, are not tunable. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1003762