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Daniel Horák - One of the best experts on this subject based on the ideXlab platform.
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Reductively Degradable Poly(2-Hydroxyethyl Methacrylate) Hydrogels with Oriented Porosity for Tissue Engineering Applications
ACS Applied Materials & Interfaces, 2017Co-Authors: Hana Macková, Zdeněk Plichta, Rafał Konefał, Zhansaya Sadakbayeva, Miroslava Dušková-smrčková, Daniel Horák, Ondřej Sedláček, Helena Hlídková, Sarka KubinovaAbstract:Degradable poly(2-Hydroxyethyl Methacrylate) hydrogels were prepared from a linear copolymer (Mw = 49 kDa) of 2-Hydroxyethyl Methacrylate (HEMA), 2-(acethylthio)ethyl Methacrylate (ATEMA), and zwitterionic 2-methacryloyloxyethyl phosphorylcholine (MPC). The deprotection of ATEMA thiol groups by triethylamine followed by their gentle oxidation with 2,2′-dithiodipyridine resulted in the formation of reductively degradable polymers with disulfide bridges. Finally, a hydrogel 3D structure with an oriented porosity was obtained by gelation of the polymer in the presence of needle-like sodium acetate crystals. The pore diameter and porosity of resulting poly(2-Hydroxyethyl Methacrylate-co-2-(acethylthio)ethyl Methacrylate-co-2-methacryloyloxyethyl phosphorylcholine) [P(HEMA-ATEMA-MPC)] hydrogels varied between 59 and 65 μm and between 70 and 79.6 vol % according to Hg porosimetry, and complete degradation of these materials was reached in 86 days in 0.33 mmol solution of l-cysteine/L in phosphate buffer. The cr...
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Reductively Degradable Poly(2-Hydroxyethyl Methacrylate) Hydrogels with Oriented Porosity for Tissue Engineering Applications.
ACS applied materials & interfaces, 2017Co-Authors: Hana Macková, Zdeněk Plichta, Rafał Konefał, Zhansaya Sadakbayeva, Miroslava Dušková-smrčková, Daniel Horák, Ondřej Sedláček, Helena Hlídková, Sarka KubinovaAbstract:Degradable poly(2-Hydroxyethyl Methacrylate) hydrogels were prepared from a linear copolymer (Mw = 49 kDa) of 2-Hydroxyethyl Methacrylate (HEMA), 2-(acethylthio)ethyl Methacrylate (ATEMA), and zwitterionic 2-methacryloyloxyethyl phosphorylcholine (MPC). The deprotection of ATEMA thiol groups by triethylamine followed by their gentle oxidation with 2,2'-dithiodipyridine resulted in the formation of reductively degradable polymers with disulfide bridges. Finally, a hydrogel 3D structure with an oriented porosity was obtained by gelation of the polymer in the presence of needle-like sodium acetate crystals. The pore diameter and porosity of resulting poly(2-Hydroxyethyl Methacrylate-co-2-(acethylthio)ethyl Methacrylate-co-2-methacryloyloxyethyl phosphorylcholine) [P(HEMA-ATEMA-MPC)] hydrogels varied between 59 and 65 μm and between 70 and 79.6 vol % according to Hg porosimetry, and complete degradation of these materials was reached in 86 days in 0.33 mmol solution of l-cysteine/L in phosphate buffer. The cross-linked P(HEMA-ATEMA-MPC) hydrogels were evaluated as a possible support for human mesenchymal stem cells (MSCs). No cytotoxicity was found for the un-cross-linked thiol-containing and protected P(HEMA-ATEMA-MPC) chains up to a concentration of 5 and 1 wt % in α-minimum essential medium, respectively.
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cholesterol modified superporous poly 2 Hydroxyethyl Methacrylate scaffolds for tissue engineering
Biomaterials, 2009Co-Authors: Sarka Kubinova, Daniel Horák, Eva SykováAbstract:Modifications of poly(2-Hydroxyethyl Methacrylate) (PHEMA) with cholesterol and laminin have been developed to design scaffolds that promote cell–surface interaction. Cholesterol-modified superporous PHEMA scaffolds have been prepared by the bulk radical copolymerization of 2-Hydroxyethyl Methacrylate (HEMA), cholesterol Methacrylate (CHLMA) and the cross-linking agent ethylene diMethacrylate (EDMA) in the presence of ammonium oxalate crystals to introduce interconnected superpores in the matrix. With the aim of immobilizing laminin (LN), carboxyl groups were also introduced to the scaffold by the copolymerization of the above monomers with 2-[(methoxycarbonyl)methoxy]ethyl Methacrylate (MCMEMA). Subsequently, the MCMEMA moiety in the resulting hydrogel was hydrolyzed to [2(methacryloyloxy)ethoxy]acetic acid (MOEAA), and laminin was immobilized via carbodiimide and N-hydroxysulfosuccinimide chemistry. The attachment, viability and morphology of mesenchymal stem cells (MSCs) were evaluated on both nonporous and superporous laminin-modified as well as lamininunmodified PHEMA and poly(2-Hydroxyethyl Methacrylate-co-cholesterol Methacrylate) P(HEMA– CHLMA) hydrogels. Neat PHEMA and laminin-modified PHEMA (LN–PHEMA) scaffolds facilitated MSC attachment, but did not support cell spreading and proliferation; the viability of the attached cells decreased with time of cultivation. In contrast, MSCs spread and proliferated on P(HEMA–CHLMA) and LN-P(HEMA–CHLMA) hydrogels.
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superporous poly 2 Hydroxyethyl Methacrylate based scaffolds preparation and characterization
Polymer, 2008Co-Authors: Daniel Horák, Helena Hlídková, J Hradil, Monika Lapcikova, Miroslav SloufAbstract:Abstract Superporous poly(2-Hydroxyethyl Methacrylate) (PHEMA) scaffolds with pore size from 10 1 to 10 2 μm range were prepared by radical polymerization of 2-Hydroxyethyl Methacrylate (HEMA) with 2 wt.% ethylene diMethacrylate (EDMA) with the aim to obtain a support for cell cultivation. Superpores were formed by salt-leaching technique using NaCl or (NH 4 ) 2 SO 4 as a porogen. Addition of liquid porogen (cyclohexanol/dodecan-1-ol (CyOH/DOH) = 9/1 w/w) to the polymerization mixture did not substantially affect the formation of meso- and macropores. The prepared slabs were characterized by several methods including water and cyclohexane regain by centrifugation, water regain by suction, scanning electron microscopy (SEM), mercury porosimetry and dynamic desorption of nitrogen. High-vacuum scanning electron microscopy (HVSEM) confirmed permeability of hydrogel slabs to 8-μm microspheres, whereas low-vacuum scanning electron microscopy (LVSEM) at cryo-conditions showed the undeformed structure of the frozen slabs. Interconnection of pores in the PHEMA slabs was proved. Water regain estimated by centrifugation method did not include volume of large superpores (imprints of porogen crystals), in contrast to water regain by suction method. The porosities of the slabs ranging from 81 to 91% were proportional to the volume of porogen in the feed.
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Effect of inert components on the porous structure of 2-Hydroxyethyl Methacrylate-ethylene diMethacrylate copolymers
Polymer, 1996Co-Authors: Daniel Horák, Frantisˇek Lednický, Miroslav BlehaAbstract:The products obtained by suspension copolymerization of 2-Hydroxyethyl Methacrylate with ethylene diMethacrylate in water in the presence of 1-dodecanol and cyclohexanol as inert diluents were characterized by scanning electron microscopy, mercury porosimetry, water and cyclohexane regain and volume swelling experiments. The porosity of the resulting poly(2-Hydroxyethyl Methacrylate) beads was readily adjusted by a change in the ratio of 1-dodecanol (non-solvating diluent) to cyclohexanol (solvating diluent). The morphological structure of the porous samples was also influenced by the choice of drying technique. Freeze-drying of samples swollen in water increased porosity compared to samples air-dried from ether.
Sarka Kubinova - One of the best experts on this subject based on the ideXlab platform.
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Reductively Degradable Poly(2-Hydroxyethyl Methacrylate) Hydrogels with Oriented Porosity for Tissue Engineering Applications.
ACS applied materials & interfaces, 2017Co-Authors: Hana Macková, Zdeněk Plichta, Rafał Konefał, Zhansaya Sadakbayeva, Miroslava Dušková-smrčková, Daniel Horák, Ondřej Sedláček, Helena Hlídková, Sarka KubinovaAbstract:Degradable poly(2-Hydroxyethyl Methacrylate) hydrogels were prepared from a linear copolymer (Mw = 49 kDa) of 2-Hydroxyethyl Methacrylate (HEMA), 2-(acethylthio)ethyl Methacrylate (ATEMA), and zwitterionic 2-methacryloyloxyethyl phosphorylcholine (MPC). The deprotection of ATEMA thiol groups by triethylamine followed by their gentle oxidation with 2,2'-dithiodipyridine resulted in the formation of reductively degradable polymers with disulfide bridges. Finally, a hydrogel 3D structure with an oriented porosity was obtained by gelation of the polymer in the presence of needle-like sodium acetate crystals. The pore diameter and porosity of resulting poly(2-Hydroxyethyl Methacrylate-co-2-(acethylthio)ethyl Methacrylate-co-2-methacryloyloxyethyl phosphorylcholine) [P(HEMA-ATEMA-MPC)] hydrogels varied between 59 and 65 μm and between 70 and 79.6 vol % according to Hg porosimetry, and complete degradation of these materials was reached in 86 days in 0.33 mmol solution of l-cysteine/L in phosphate buffer. The cross-linked P(HEMA-ATEMA-MPC) hydrogels were evaluated as a possible support for human mesenchymal stem cells (MSCs). No cytotoxicity was found for the un-cross-linked thiol-containing and protected P(HEMA-ATEMA-MPC) chains up to a concentration of 5 and 1 wt % in α-minimum essential medium, respectively.
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Reductively Degradable Poly(2-Hydroxyethyl Methacrylate) Hydrogels with Oriented Porosity for Tissue Engineering Applications
ACS Applied Materials & Interfaces, 2017Co-Authors: Hana Macková, Zdeněk Plichta, Rafał Konefał, Zhansaya Sadakbayeva, Miroslava Dušková-smrčková, Daniel Horák, Ondřej Sedláček, Helena Hlídková, Sarka KubinovaAbstract:Degradable poly(2-Hydroxyethyl Methacrylate) hydrogels were prepared from a linear copolymer (Mw = 49 kDa) of 2-Hydroxyethyl Methacrylate (HEMA), 2-(acethylthio)ethyl Methacrylate (ATEMA), and zwitterionic 2-methacryloyloxyethyl phosphorylcholine (MPC). The deprotection of ATEMA thiol groups by triethylamine followed by their gentle oxidation with 2,2′-dithiodipyridine resulted in the formation of reductively degradable polymers with disulfide bridges. Finally, a hydrogel 3D structure with an oriented porosity was obtained by gelation of the polymer in the presence of needle-like sodium acetate crystals. The pore diameter and porosity of resulting poly(2-Hydroxyethyl Methacrylate-co-2-(acethylthio)ethyl Methacrylate-co-2-methacryloyloxyethyl phosphorylcholine) [P(HEMA-ATEMA-MPC)] hydrogels varied between 59 and 65 μm and between 70 and 79.6 vol % according to Hg porosimetry, and complete degradation of these materials was reached in 86 days in 0.33 mmol solution of l-cysteine/L in phosphate buffer. The cr...
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cholesterol modified superporous poly 2 Hydroxyethyl Methacrylate scaffolds for tissue engineering
Biomaterials, 2009Co-Authors: Sarka Kubinova, Daniel Horák, Eva SykováAbstract:Modifications of poly(2-Hydroxyethyl Methacrylate) (PHEMA) with cholesterol and laminin have been developed to design scaffolds that promote cell–surface interaction. Cholesterol-modified superporous PHEMA scaffolds have been prepared by the bulk radical copolymerization of 2-Hydroxyethyl Methacrylate (HEMA), cholesterol Methacrylate (CHLMA) and the cross-linking agent ethylene diMethacrylate (EDMA) in the presence of ammonium oxalate crystals to introduce interconnected superpores in the matrix. With the aim of immobilizing laminin (LN), carboxyl groups were also introduced to the scaffold by the copolymerization of the above monomers with 2-[(methoxycarbonyl)methoxy]ethyl Methacrylate (MCMEMA). Subsequently, the MCMEMA moiety in the resulting hydrogel was hydrolyzed to [2(methacryloyloxy)ethoxy]acetic acid (MOEAA), and laminin was immobilized via carbodiimide and N-hydroxysulfosuccinimide chemistry. The attachment, viability and morphology of mesenchymal stem cells (MSCs) were evaluated on both nonporous and superporous laminin-modified as well as lamininunmodified PHEMA and poly(2-Hydroxyethyl Methacrylate-co-cholesterol Methacrylate) P(HEMA– CHLMA) hydrogels. Neat PHEMA and laminin-modified PHEMA (LN–PHEMA) scaffolds facilitated MSC attachment, but did not support cell spreading and proliferation; the viability of the attached cells decreased with time of cultivation. In contrast, MSCs spread and proliferated on P(HEMA–CHLMA) and LN-P(HEMA–CHLMA) hydrogels.
Andrew K. Whittaker - One of the best experts on this subject based on the ideXlab platform.
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Effect of changes in the surface chemistry and topography of poly(2-Hydroxyethyl Methacrylate) on the in vitro attachment of human corneal epithelial cells
Journal of Bioactive and Compatible Polymers, 2017Co-Authors: Miriem Santander-borrego, Audra M. A. Shadforth, Traian V Chirila, Andrew K. Whittaker, Idriss BlakeyAbstract:The effects on cell adhesion induced by changes in the topography and chemistry of poly(2-Hydroxyethyl Methacrylate) hydrogel surfaces were investigated in vitro using the human corneal epithelial cell line, HCE-T. Poly(2-Hydroxyethyl Methacrylate) surfaces with a lotus-leaf-like topography and poly(2-Hydroxyethyl Methacrylate) surfaces with a flat topography, but functionalized with the cell-adhesive peptide sequence Arg-Gly-Asp, both enhanced attachment of HCE-T cells as compared to flat, non-functionalized poly(2-Hydroxyethyl Methacrylate) surfaces. However, the simultaneous existence on the same poly(2-Hydroxyethyl Methacrylate) surface of Arg-Gly-Asp motifs and of lotus-leaf-like topographical patterns led to an apparently antagonistic effect reflected in reduced cell attachment. The study provided additional evidence of the complexity of the cell-biomaterial interactions.
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Effect of changes in the surface chemistry and topography of poly(2-Hydroxyethyl Methacrylate) on the in vitro attachment of human corneal epithelial cells
Journal of Bioactive and Compatible Polymers, 2017Co-Authors: Miriem Santander-borrego, Audra M. A. Shadforth, Traian V Chirila, Andrew K. Whittaker, Idriss BlakeyAbstract:The effects on cell adhesion induced by changes in the topography and chemistry of poly(2-Hydroxyethyl Methacrylate) hydrogel surfaces were investigated in vitro using the human corneal epithelial cell line, HCE-T. Poly(2-Hydroxyethyl Methacrylate) surfaces with a lotus-leaf-like topography and poly(2-Hydroxyethyl Methacrylate) surfaces with a flat topography, but functionalized with the cell-adhesive peptide sequence Arg-Gly-Asp, both enhanced attachment of HCE-T cells as compared to flat, non-functionalized poly(2-Hydroxyethyl Methacrylate) surfaces. However, the simultaneous existence on the same poly(2-Hydroxyethyl Methacrylate) surface of Arg-Gly-Asp motifs and of lotus-leaf-like topographical patterns led to an apparently antagonistic effect reflected in reduced cell attachment. The study provided additional evidence of the complexity of the cell-biomaterial interactions.
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Water sorption by poly(tetrahydrofurfuryl Methacrylate‐co‐2‐Hydroxyethyl Methacrylate). I. A mass‐uptake study
Journal of Polymer Science Part B: Polymer Physics, 2000Co-Authors: Phuong Y. Ghi, David J. Hill, Andrew K. WhittakerAbstract:Cylindrical samples (approximate to 5 mm x 20 mm) of poly(2-Hydroxyethyl Methacrylate) and copolymers of 2-Hydroxyethyl Methacrylate and furfuryl Methacrylate were prepared, and the sorption of water into these cylinders was studied by the mass-uptake method and by the measurement of the volume change at equilibrium. The equilibrium water content and volume change for the cylinders both varied systematically with the copolymer composition. The diffusion of water into the cylinders followed Fickian behavior, with the diffusion coefficients, dependent on the copolymer composition, varying from 2.00 x 10(-11) m(2)s(-1) for poly(2-Hydroxyethyl Methacrylate) to 5.00 x 10(-12) m(2)s(-1) for poly(2-Hydroxyethyl Methacrylate-co-tetrahydrofurfuryl Methacrylate) with a 1:4 composition. The polymers that were rich in 2-Hydroxyethyl methacrylatc were characterized by a water-sorption overshoot, which was attributed to a slow reorientation of the polymer chains in the swollen rubbery regions formed after wafer sorption. (C) 2000 John Wiley & Sons, Inc.
Helena Hlídková - One of the best experts on this subject based on the ideXlab platform.
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Reductively Degradable Poly(2-Hydroxyethyl Methacrylate) Hydrogels with Oriented Porosity for Tissue Engineering Applications
ACS Applied Materials & Interfaces, 2017Co-Authors: Hana Macková, Zdeněk Plichta, Rafał Konefał, Zhansaya Sadakbayeva, Miroslava Dušková-smrčková, Daniel Horák, Ondřej Sedláček, Helena Hlídková, Sarka KubinovaAbstract:Degradable poly(2-Hydroxyethyl Methacrylate) hydrogels were prepared from a linear copolymer (Mw = 49 kDa) of 2-Hydroxyethyl Methacrylate (HEMA), 2-(acethylthio)ethyl Methacrylate (ATEMA), and zwitterionic 2-methacryloyloxyethyl phosphorylcholine (MPC). The deprotection of ATEMA thiol groups by triethylamine followed by their gentle oxidation with 2,2′-dithiodipyridine resulted in the formation of reductively degradable polymers with disulfide bridges. Finally, a hydrogel 3D structure with an oriented porosity was obtained by gelation of the polymer in the presence of needle-like sodium acetate crystals. The pore diameter and porosity of resulting poly(2-Hydroxyethyl Methacrylate-co-2-(acethylthio)ethyl Methacrylate-co-2-methacryloyloxyethyl phosphorylcholine) [P(HEMA-ATEMA-MPC)] hydrogels varied between 59 and 65 μm and between 70 and 79.6 vol % according to Hg porosimetry, and complete degradation of these materials was reached in 86 days in 0.33 mmol solution of l-cysteine/L in phosphate buffer. The cr...
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Reductively Degradable Poly(2-Hydroxyethyl Methacrylate) Hydrogels with Oriented Porosity for Tissue Engineering Applications.
ACS applied materials & interfaces, 2017Co-Authors: Hana Macková, Zdeněk Plichta, Rafał Konefał, Zhansaya Sadakbayeva, Miroslava Dušková-smrčková, Daniel Horák, Ondřej Sedláček, Helena Hlídková, Sarka KubinovaAbstract:Degradable poly(2-Hydroxyethyl Methacrylate) hydrogels were prepared from a linear copolymer (Mw = 49 kDa) of 2-Hydroxyethyl Methacrylate (HEMA), 2-(acethylthio)ethyl Methacrylate (ATEMA), and zwitterionic 2-methacryloyloxyethyl phosphorylcholine (MPC). The deprotection of ATEMA thiol groups by triethylamine followed by their gentle oxidation with 2,2'-dithiodipyridine resulted in the formation of reductively degradable polymers with disulfide bridges. Finally, a hydrogel 3D structure with an oriented porosity was obtained by gelation of the polymer in the presence of needle-like sodium acetate crystals. The pore diameter and porosity of resulting poly(2-Hydroxyethyl Methacrylate-co-2-(acethylthio)ethyl Methacrylate-co-2-methacryloyloxyethyl phosphorylcholine) [P(HEMA-ATEMA-MPC)] hydrogels varied between 59 and 65 μm and between 70 and 79.6 vol % according to Hg porosimetry, and complete degradation of these materials was reached in 86 days in 0.33 mmol solution of l-cysteine/L in phosphate buffer. The cross-linked P(HEMA-ATEMA-MPC) hydrogels were evaluated as a possible support for human mesenchymal stem cells (MSCs). No cytotoxicity was found for the un-cross-linked thiol-containing and protected P(HEMA-ATEMA-MPC) chains up to a concentration of 5 and 1 wt % in α-minimum essential medium, respectively.
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superporous poly 2 Hydroxyethyl Methacrylate based scaffolds preparation and characterization
Polymer, 2008Co-Authors: Daniel Horák, Helena Hlídková, J Hradil, Monika Lapcikova, Miroslav SloufAbstract:Abstract Superporous poly(2-Hydroxyethyl Methacrylate) (PHEMA) scaffolds with pore size from 10 1 to 10 2 μm range were prepared by radical polymerization of 2-Hydroxyethyl Methacrylate (HEMA) with 2 wt.% ethylene diMethacrylate (EDMA) with the aim to obtain a support for cell cultivation. Superpores were formed by salt-leaching technique using NaCl or (NH 4 ) 2 SO 4 as a porogen. Addition of liquid porogen (cyclohexanol/dodecan-1-ol (CyOH/DOH) = 9/1 w/w) to the polymerization mixture did not substantially affect the formation of meso- and macropores. The prepared slabs were characterized by several methods including water and cyclohexane regain by centrifugation, water regain by suction, scanning electron microscopy (SEM), mercury porosimetry and dynamic desorption of nitrogen. High-vacuum scanning electron microscopy (HVSEM) confirmed permeability of hydrogel slabs to 8-μm microspheres, whereas low-vacuum scanning electron microscopy (LVSEM) at cryo-conditions showed the undeformed structure of the frozen slabs. Interconnection of pores in the PHEMA slabs was proved. Water regain estimated by centrifugation method did not include volume of large superpores (imprints of porogen crystals), in contrast to water regain by suction method. The porosities of the slabs ranging from 81 to 91% were proportional to the volume of porogen in the feed.
Idriss Blakey - One of the best experts on this subject based on the ideXlab platform.
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Effect of changes in the surface chemistry and topography of poly(2-Hydroxyethyl Methacrylate) on the in vitro attachment of human corneal epithelial cells
Journal of Bioactive and Compatible Polymers, 2017Co-Authors: Miriem Santander-borrego, Audra M. A. Shadforth, Traian V Chirila, Andrew K. Whittaker, Idriss BlakeyAbstract:The effects on cell adhesion induced by changes in the topography and chemistry of poly(2-Hydroxyethyl Methacrylate) hydrogel surfaces were investigated in vitro using the human corneal epithelial cell line, HCE-T. Poly(2-Hydroxyethyl Methacrylate) surfaces with a lotus-leaf-like topography and poly(2-Hydroxyethyl Methacrylate) surfaces with a flat topography, but functionalized with the cell-adhesive peptide sequence Arg-Gly-Asp, both enhanced attachment of HCE-T cells as compared to flat, non-functionalized poly(2-Hydroxyethyl Methacrylate) surfaces. However, the simultaneous existence on the same poly(2-Hydroxyethyl Methacrylate) surface of Arg-Gly-Asp motifs and of lotus-leaf-like topographical patterns led to an apparently antagonistic effect reflected in reduced cell attachment. The study provided additional evidence of the complexity of the cell-biomaterial interactions.
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Effect of changes in the surface chemistry and topography of poly(2-Hydroxyethyl Methacrylate) on the in vitro attachment of human corneal epithelial cells
Journal of Bioactive and Compatible Polymers, 2017Co-Authors: Miriem Santander-borrego, Audra M. A. Shadforth, Traian V Chirila, Andrew K. Whittaker, Idriss BlakeyAbstract:The effects on cell adhesion induced by changes in the topography and chemistry of poly(2-Hydroxyethyl Methacrylate) hydrogel surfaces were investigated in vitro using the human corneal epithelial cell line, HCE-T. Poly(2-Hydroxyethyl Methacrylate) surfaces with a lotus-leaf-like topography and poly(2-Hydroxyethyl Methacrylate) surfaces with a flat topography, but functionalized with the cell-adhesive peptide sequence Arg-Gly-Asp, both enhanced attachment of HCE-T cells as compared to flat, non-functionalized poly(2-Hydroxyethyl Methacrylate) surfaces. However, the simultaneous existence on the same poly(2-Hydroxyethyl Methacrylate) surface of Arg-Gly-Asp motifs and of lotus-leaf-like topographical patterns led to an apparently antagonistic effect reflected in reduced cell attachment. The study provided additional evidence of the complexity of the cell-biomaterial interactions.
