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1. Hybrid biodegradable electrospun scaffolds based on poly(l-lactic acid) and reduced graphene oxide with improved piezoelectric response

Author

Pariy, Igor O., Chernozem, Roman, V, Chernozem, Polina, V, Mukhortova, Yulia R., Skirtach, Andre G., Shvartsman, Vladimir V., Lupascu, Doru C., Surmeneva, Maria A., Mathur, Sanjay, Surmenev, Roman A., Pariy, Igor O., Chernozem, Roman, V, Chernozem, Polina, V, Mukhortova, Yulia R., Skirtach, Andre G., Shvartsman, Vladimir V., Lupascu, Doru C., Surmeneva, Maria A., Mathur, Sanjay, and Surmenev, Roman A.

Abstract

Piezoelectric poly-L-lactide (PLLA) is a biodegradable polymer used in various biomedical applications. However, tailoring and controlling the structure of PLLA to enhance its piezoelectric response remains a challenge. In this work, extensive characterization was performed to reveal the effect of the reduced graphene oxide (rGO) content (0.2, 0.7, and 1.0 wt%) on the morphology, structure, thermal and piezoelectric behavior of PLLA scaffolds. Randomly oriented homogeneous fibers and a quasi-amorphous structure for pure PLLA and hybrid PLLA-rGO scaffolds were revealed. The addition of rGO affected the molecular structure of the PLLA scaffolds: for example, the number of polar C=O functional groups was increased. Increasing the content of rGO to 1 wt% resulted in decreased glass transition and melting temperatures and increased the degree of crystallinity of the scaffolds. The addition of 0.2 wt% rGO enhanced the effective local vertical and lateral piezoresponses by 2.3 and 15.4 times, respectively, in comparison with pure PLLA fibers. The presence of the shear piezoelectric alpha-phase (P2(1)2(1)2(1)) in uniaxially oriented PLLA fibers and C=O bond rotation in the polymer chains explained the observed piezoresponse. Thus, this study revealed routes to prepare hybrid biodegradable scaffolds with enhanced piezoresponse for tissue engineering applications.

Published
2022

2. Efficient long-range conduction in cable bacteria through nickel protein wires

Author

Boschker, Henricus T.S., Cook, Perran L.M., Polerecky, Lubos, Eachambadi, Raghavendran Thiruvallur, Lozano, Helena, Hidalgo-Martinez, Silvia, Khalenkow, Dmitry, Spampinato, Valentina, Claes, Nathalie, Kundu, Paromita, Wang, Da, Bals, Sara, Sand, Karina K., Cavezza, Francesca, Hauffman, Tom, Bjerg, Jesper Tataru, Skirtach, Andre G., Kochan, Kamila, McKee, Merrilyn, Wood, Bayden, Bedolla, Diana, Gianoncelli, Alessandra, Geerlings, Nicole M.J., Van Gerven, Nani, Remaut, Han, Geelhoed, Jeanine S., Millan-Solsona, Ruben, Fumagalli, Laura, Nielsen, Lars Peter, Franquet, Alexis, Manca, Jean V., Gomila, Gabriel, Meysman, Filip J.R., Boschker, Henricus T.S., Cook, Perran L.M., Polerecky, Lubos, Eachambadi, Raghavendran Thiruvallur, Lozano, Helena, Hidalgo-Martinez, Silvia, Khalenkow, Dmitry, Spampinato, Valentina, Claes, Nathalie, Kundu, Paromita, Wang, Da, Bals, Sara, Sand, Karina K., Cavezza, Francesca, Hauffman, Tom, Bjerg, Jesper Tataru, Skirtach, Andre G., Kochan, Kamila, McKee, Merrilyn, Wood, Bayden, Bedolla, Diana, Gianoncelli, Alessandra, Geerlings, Nicole M.J., Van Gerven, Nani, Remaut, Han, Geelhoed, Jeanine S., Millan-Solsona, Ruben, Fumagalli, Laura, Nielsen, Lars Peter, Franquet, Alexis, Manca, Jean V., Gomila, Gabriel, and Meysman, Filip J.R.

Abstract

Filamentous cable bacteria display long-range electron transport, generating electrical currents over centimeter distances through a highly ordered network of fibers embedded in their cell envelope. The conductivity of these periplasmic wires is exceptionally high for a biological material, but their chemical structure and underlying electron transport mechanism remain unresolved. Here, we combine high-resolution microscopy, spectroscopy, and chemical imaging on individual cable bacterium filaments to demonstrate that the periplasmic wires consist of a conductive protein core surrounded by an insulating protein shell layer. The core proteins contain a sulfur-ligated nickel cofactor, and conductivity decreases when nickel is oxidized or selectively removed. The involvement of nickel as the active metal in biological conduction is remarkable, and suggests a hitherto unknown form of electron transport that enables efficient conduction in centimeter-long protein structures.

Published
2021

3. The influence of Ca/Mg ratio on autogelation of hydrogel biomaterials with bioceramic compounds

Author

Abalymov, Anatoly, Lengert, Ekaterina, Van der Meeren, Louis, Saveleva, Mariia, Ivanova, Anna, Douglas, Timothy, Skirtach, Andre G., Volodkin, Dmitry, Parakhonskiy, Bogdan V, Abalymov, Anatoly, Lengert, Ekaterina, Van der Meeren, Louis, Saveleva, Mariia, Ivanova, Anna, Douglas, Timothy, Skirtach, Andre G., Volodkin, Dmitry, and Parakhonskiy, Bogdan V

Published
2021

4. Efficient long-range conduction in cable bacteria through nickel protein wires

Author

Geochemistry, Bio-, hydro-, and environmental geochemistry, Boschker, Henricus T.S., Cook, Perran L.M., Polerecky, Lubos, Eachambadi, Raghavendran Thiruvallur, Lozano, Helena, Hidalgo-Martinez, Silvia, Khalenkow, Dmitry, Spampinato, Valentina, Claes, Nathalie, Kundu, Paromita, Wang, Da, Bals, Sara, Sand, Karina K., Cavezza, Francesca, Hauffman, Tom, Bjerg, Jesper Tataru, Skirtach, Andre G., Kochan, Kamila, McKee, Merrilyn, Wood, Bayden, Bedolla, Diana, Gianoncelli, Alessandra, Geerlings, Nicole M.J., Van Gerven, Nani, Remaut, Han, Geelhoed, Jeanine S., Millan-Solsona, Ruben, Fumagalli, Laura, Nielsen, Lars Peter, Franquet, Alexis, Manca, Jean V., Gomila, Gabriel, Meysman, Filip J.R., Geochemistry, Bio-, hydro-, and environmental geochemistry, Boschker, Henricus T.S., Cook, Perran L.M., Polerecky, Lubos, Eachambadi, Raghavendran Thiruvallur, Lozano, Helena, Hidalgo-Martinez, Silvia, Khalenkow, Dmitry, Spampinato, Valentina, Claes, Nathalie, Kundu, Paromita, Wang, Da, Bals, Sara, Sand, Karina K., Cavezza, Francesca, Hauffman, Tom, Bjerg, Jesper Tataru, Skirtach, Andre G., Kochan, Kamila, McKee, Merrilyn, Wood, Bayden, Bedolla, Diana, Gianoncelli, Alessandra, Geerlings, Nicole M.J., Van Gerven, Nani, Remaut, Han, Geelhoed, Jeanine S., Millan-Solsona, Ruben, Fumagalli, Laura, Nielsen, Lars Peter, Franquet, Alexis, Manca, Jean V., Gomila, Gabriel, and Meysman, Filip J.R.

Published
2021

5. Enhanced piezoresponse and surface electric potential of hybrid biodegradable polyhydroxybutyrate scaffolds functionalized with reduced graphene oxide for tissue engineering

Author

Chernozem, Roman, V, Romanyuk, Konstantin N., Grubova, Irina, Chernozem, Polina, V, Surmeneva, Maria A., Mukhortova, Yulia R., Wilhelm, Michael, Ludwig, Tim, Mathur, Sanjay, Kholkin, Andrei L., Neyts, Erik, Parakhonskiy, Bogdan, Skirtach, Andre G., Surmenev, Roman A., Chernozem, Roman, V, Romanyuk, Konstantin N., Grubova, Irina, Chernozem, Polina, V, Surmeneva, Maria A., Mukhortova, Yulia R., Wilhelm, Michael, Ludwig, Tim, Mathur, Sanjay, Kholkin, Andrei L., Neyts, Erik, Parakhonskiy, Bogdan, Skirtach, Andre G., and Surmenev, Roman A.

Abstract

Piezoelectricity is considered to be one of the key functionalities in biomaterials to boost bone tissue regeneration, however, integrating biocompatibility, biodegradability and 3D structure with pronounced piezoresponse remains a material challenge. Herein, novel hybrid biocompatible 3D scaffolds based on biodegradable poly(3-hydroxybutyrate) (PHB) and reduced graphene oxide (rGO) flakes have been developed. Nanoscale insights revealed a more homogenous distribution and superior surface potential values of PHB fibers (33 +/- 29 mV) with increasing rGO content up to 1.0 wt% (314 +/- 31 mV). The maximum effective piezoresponse was detected at 0.7 wt% rGO content, demonstrating 2.5 and 1.7 times higher out-of-plane and in-plane values, respectively, than that for pure PHB fibers. The rGO addition led to enhanced zigzag chain formation between paired lamellae in PHB fibers. In contrast, a further increase in rGO content reduced the alpha-crystal size and prevented zigzag chain conformation. A corresponding model explaining structural and molecular changes caused by rGO addition in electrospun PHB fibers is proposed. In addition, finite element analysis revealed a negligible vertical piezoresponse compared to lateral piezoresponse in uniaxially oriented PHB fibers based on alpha-phase (P2(1)2(1)2(1) space group). Thus, the present study demonstrates promising results for the development of biodegradable hybrid 3D scaffolds with an enhanced piezoresponse for various tissue engineering applications.

Published
2021

6. Efficient long-range conduction in cable bacteria through nickel protein wires

Author

Geochemistry, Bio-, hydro-, and environmental geochemistry, Boschker, Henricus T.S., Cook, Perran L.M., Polerecky, Lubos, Eachambadi, Raghavendran Thiruvallur, Lozano, Helena, Hidalgo-Martinez, Silvia, Khalenkow, Dmitry, Spampinato, Valentina, Claes, Nathalie, Kundu, Paromita, Wang, Da, Bals, Sara, Sand, Karina K., Cavezza, Francesca, Hauffman, Tom, Bjerg, Jesper Tataru, Skirtach, Andre G., Kochan, Kamila, McKee, Merrilyn, Wood, Bayden, Bedolla, Diana, Gianoncelli, Alessandra, Geerlings, Nicole M.J., Van Gerven, Nani, Remaut, Han, Geelhoed, Jeanine S., Millan-Solsona, Ruben, Fumagalli, Laura, Nielsen, Lars Peter, Franquet, Alexis, Manca, Jean V., Gomila, Gabriel, Meysman, Filip J.R., Geochemistry, Bio-, hydro-, and environmental geochemistry, Boschker, Henricus T.S., Cook, Perran L.M., Polerecky, Lubos, Eachambadi, Raghavendran Thiruvallur, Lozano, Helena, Hidalgo-Martinez, Silvia, Khalenkow, Dmitry, Spampinato, Valentina, Claes, Nathalie, Kundu, Paromita, Wang, Da, Bals, Sara, Sand, Karina K., Cavezza, Francesca, Hauffman, Tom, Bjerg, Jesper Tataru, Skirtach, Andre G., Kochan, Kamila, McKee, Merrilyn, Wood, Bayden, Bedolla, Diana, Gianoncelli, Alessandra, Geerlings, Nicole M.J., Van Gerven, Nani, Remaut, Han, Geelhoed, Jeanine S., Millan-Solsona, Ruben, Fumagalli, Laura, Nielsen, Lars Peter, Franquet, Alexis, Manca, Jean V., Gomila, Gabriel, and Meysman, Filip J.R.

Published
2021

7. Efficient long-range conduction in cable bacteria through nickel protein wires

Author

Geochemistry, Bio-, hydro-, and environmental geochemistry, Boschker, Henricus T.S., Cook, Perran L.M., Polerecky, Lubos, Eachambadi, Raghavendran Thiruvallur, Lozano, Helena, Hidalgo-Martinez, Silvia, Khalenkow, Dmitry, Spampinato, Valentina, Claes, Nathalie, Kundu, Paromita, Wang, Da, Bals, Sara, Sand, Karina K., Cavezza, Francesca, Hauffman, Tom, Bjerg, Jesper Tataru, Skirtach, Andre G., Kochan, Kamila, McKee, Merrilyn, Wood, Bayden, Bedolla, Diana, Gianoncelli, Alessandra, Geerlings, Nicole M.J., Van Gerven, Nani, Remaut, Han, Geelhoed, Jeanine S., Millan-Solsona, Ruben, Fumagalli, Laura, Nielsen, Lars Peter, Franquet, Alexis, Manca, Jean V., Gomila, Gabriel, Meysman, Filip J.R., Geochemistry, Bio-, hydro-, and environmental geochemistry, Boschker, Henricus T.S., Cook, Perran L.M., Polerecky, Lubos, Eachambadi, Raghavendran Thiruvallur, Lozano, Helena, Hidalgo-Martinez, Silvia, Khalenkow, Dmitry, Spampinato, Valentina, Claes, Nathalie, Kundu, Paromita, Wang, Da, Bals, Sara, Sand, Karina K., Cavezza, Francesca, Hauffman, Tom, Bjerg, Jesper Tataru, Skirtach, Andre G., Kochan, Kamila, McKee, Merrilyn, Wood, Bayden, Bedolla, Diana, Gianoncelli, Alessandra, Geerlings, Nicole M.J., Van Gerven, Nani, Remaut, Han, Geelhoed, Jeanine S., Millan-Solsona, Ruben, Fumagalli, Laura, Nielsen, Lars Peter, Franquet, Alexis, Manca, Jean V., Gomila, Gabriel, and Meysman, Filip J.R.

Published
2021

8. Enhanced piezoresponse and surface electric potential of hybrid biodegradable polyhydroxybutyrate scaffolds functionalized with reduced graphene oxide for tissue engineering

Author

Chernozem, Roman, V, Romanyuk, Konstantin N., Grubova, Irina, Chernozem, Polina, V, Surmeneva, Maria A., Mukhortova, Yulia R., Wilhelm, Michael, Ludwig, Tim, Mathur, Sanjay, Kholkin, Andrei L., Neyts, Erik, Parakhonskiy, Bogdan, Skirtach, Andre G., Surmenev, Roman A., Chernozem, Roman, V, Romanyuk, Konstantin N., Grubova, Irina, Chernozem, Polina, V, Surmeneva, Maria A., Mukhortova, Yulia R., Wilhelm, Michael, Ludwig, Tim, Mathur, Sanjay, Kholkin, Andrei L., Neyts, Erik, Parakhonskiy, Bogdan, Skirtach, Andre G., and Surmenev, Roman A.

Abstract

Piezoelectricity is considered to be one of the key functionalities in biomaterials to boost bone tissue regeneration, however, integrating biocompatibility, biodegradability and 3D structure with pronounced piezoresponse remains a material challenge. Herein, novel hybrid biocompatible 3D scaffolds based on biodegradable poly(3-hydroxybutyrate) (PHB) and reduced graphene oxide (rGO) flakes have been developed. Nanoscale insights revealed a more homogenous distribution and superior surface potential values of PHB fibers (33 +/- 29 mV) with increasing rGO content up to 1.0 wt% (314 +/- 31 mV). The maximum effective piezoresponse was detected at 0.7 wt% rGO content, demonstrating 2.5 and 1.7 times higher out-of-plane and in-plane values, respectively, than that for pure PHB fibers. The rGO addition led to enhanced zigzag chain formation between paired lamellae in PHB fibers. In contrast, a further increase in rGO content reduced the alpha-crystal size and prevented zigzag chain conformation. A corresponding model explaining structural and molecular changes caused by rGO addition in electrospun PHB fibers is proposed. In addition, finite element analysis revealed a negligible vertical piezoresponse compared to lateral piezoresponse in uniaxially oriented PHB fibers based on alpha-phase (P2(1)2(1)2(1) space group). Thus, the present study demonstrates promising results for the development of biodegradable hybrid 3D scaffolds with an enhanced piezoresponse for various tissue engineering applications.

Published
2021

9. Efficient long-range conduction in cable bacteria through nickel protein wires

Author

Boschker, Henricus T. S., Cook, Perran L. M., Polerecky, Lubos, Eachambadi, Raghavendran Thiruvallur, Lozano, Helena, Hidalgo-martinez, Silvia, Khalenkow, Dmitry, Spampinato, Valentina, Claes, Nathalie, Kundu, Paromita, Wang, Da, Bals, Sara, Sand, Karina K., Cavezza, Francesca, Hauffman, Tom, Bjerg, Jesper Tataru, Skirtach, Andre G., Kochan, Kamila, Mckee, Merrilyn, Wood, Bayden, Bedolla, Diana, Gianoncelli, Alessandra, Geerlings, Nicole M. J., Van Gerven, Nani, Remaut, Han, Geelhoed, Jeanine S., Millan-solsona, Ruben, Fumagalli, Laura, Nielsen, Lars Peter, Franquet, Alexis, Manca, Jean V., Gomila, Gabriel, Meysman, Filip J. R., Boschker, Henricus T. S., Cook, Perran L. M., Polerecky, Lubos, Eachambadi, Raghavendran Thiruvallur, Lozano, Helena, Hidalgo-martinez, Silvia, Khalenkow, Dmitry, Spampinato, Valentina, Claes, Nathalie, Kundu, Paromita, Wang, Da, Bals, Sara, Sand, Karina K., Cavezza, Francesca, Hauffman, Tom, Bjerg, Jesper Tataru, Skirtach, Andre G., Kochan, Kamila, Mckee, Merrilyn, Wood, Bayden, Bedolla, Diana, Gianoncelli, Alessandra, Geerlings, Nicole M. J., Van Gerven, Nani, Remaut, Han, Geelhoed, Jeanine S., Millan-solsona, Ruben, Fumagalli, Laura, Nielsen, Lars Peter, Franquet, Alexis, Manca, Jean V., Gomila, Gabriel, and Meysman, Filip J. R.

Published
2021

10. Efficient long-range conduction in cable bacteria through nickel protein wires

Author

Boschker, Henricus T. S., Cook, Perran L. M., Polerecky, Lubos, Eachambadi, Raghavendran Thiruvallur, Lozano, Helena, Hidalgo-martinez, Silvia, Khalenkow, Dmitry, Spampinato, Valentina, Claes, Nathalie, Kundu, Paromita, Wang, Da, Bals, Sara, Sand, Karina K., Cavezza, Francesca, Hauffman, Tom, Bjerg, Jesper Tataru, Skirtach, Andre G., Kochan, Kamila, Mckee, Merrilyn, Wood, Bayden, Bedolla, Diana, Gianoncelli, Alessandra, Geerlings, Nicole M. J., Van Gerven, Nani, Remaut, Han, Geelhoed, Jeanine S., Millan-solsona, Ruben, Fumagalli, Laura, Nielsen, Lars Peter, Franquet, Alexis, Manca, Jean V., Gomila, Gabriel, Meysman, Filip J. R., Boschker, Henricus T. S., Cook, Perran L. M., Polerecky, Lubos, Eachambadi, Raghavendran Thiruvallur, Lozano, Helena, Hidalgo-martinez, Silvia, Khalenkow, Dmitry, Spampinato, Valentina, Claes, Nathalie, Kundu, Paromita, Wang, Da, Bals, Sara, Sand, Karina K., Cavezza, Francesca, Hauffman, Tom, Bjerg, Jesper Tataru, Skirtach, Andre G., Kochan, Kamila, Mckee, Merrilyn, Wood, Bayden, Bedolla, Diana, Gianoncelli, Alessandra, Geerlings, Nicole M. J., Van Gerven, Nani, Remaut, Han, Geelhoed, Jeanine S., Millan-solsona, Ruben, Fumagalli, Laura, Nielsen, Lars Peter, Franquet, Alexis, Manca, Jean V., Gomila, Gabriel, and Meysman, Filip J. R.

Published
2021

11. Enhancement of biomimetic enzymatic mineralization of gellan gum polysaccharide hydrogels by plant-derived gallotannins

Author

Douglas, Timothy, Keppler, Julia K., Vandrovcova, Marta, Plnencer, Martin, Beranova, Jana, Feuereisen, Michelle, Parakhonskiy, Bogdan V, Svenskaya, Yulia, Atkin, Vsevolod, Ivanova, Anna, Ricquier, Patrick, Balcaen, Lieve, Vanhaecke, Frank, Schieber, Andreas, Bacakova, Lucie, Skirtach, Andre G., Douglas, Timothy, Keppler, Julia K., Vandrovcova, Marta, Plnencer, Martin, Beranova, Jana, Feuereisen, Michelle, Parakhonskiy, Bogdan V, Svenskaya, Yulia, Atkin, Vsevolod, Ivanova, Anna, Ricquier, Patrick, Balcaen, Lieve, Vanhaecke, Frank, Schieber, Andreas, Bacakova, Lucie, and Skirtach, Andre G.

Abstract

Mineralization of hydrogel biomaterials with calcium phosphate (CaP) is considered advantageous for bone regeneration. Mineralization can be both induced by the enzyme alkaline phosphatase (ALP) and promoted by calcium-binding biomolecules, such as plant-derived polyphenols. In this study, ALP-loaded gellan gum (GG) hydrogels were enriched with gallotannins, a subclass of polyphenols. Five preparations were compared, namely three tannic acids of differing molecular weight (MW), pentagalloyl glucose (PGG), and a gallotannin-rich extract from mango kernel (Mangifera indica L.). Certain gallotannin preparations promoted mineralization to a greater degree than others. The various gallotannin preparations bound differently to ALP and influenced the size of aggregates of ALP, which may be related to ability to promote mineralization. Human osteoblast-like Saos-2 cells grew in eluate from mineralized hydrogels. Gallotannin incorporation impeded cell growth on hydrogels and did not impart antibacterial activity. In conclusion, gallotannin incorporation aided mineralization but reduced cytocompatibility.

Published
2020

12. Visible and NIR Upconverting Er3+–Yb3+ Luminescent Nanorattles and Other Hybrid PMO-Inorganic Structures for In Vivo Nanothermometry

Author

Condensed Matter and Interfaces, Sub Condensed Matter and Interfaces, Kaczmarek, Anna M., Suta, Markus, Rijckaert, Hannes, Abalymov, Anatolii, Van Driessche, Isabel, Skirtach, Andre G., Meijerink, Andries, Van Der Voort, Pascal, Condensed Matter and Interfaces, Sub Condensed Matter and Interfaces, Kaczmarek, Anna M., Suta, Markus, Rijckaert, Hannes, Abalymov, Anatolii, Van Driessche, Isabel, Skirtach, Andre G., Meijerink, Andries, and Van Der Voort, Pascal

Published
2020

13. Visible and NIR Upconverting Er3+–Yb3+ Luminescent Nanorattles and Other Hybrid PMO-Inorganic Structures for In Vivo Nanothermometry

Author

Condensed Matter and Interfaces, Sub Condensed Matter and Interfaces, Kaczmarek, Anna M., Suta, Markus, Rijckaert, Hannes, Abalymov, Anatolii, Van Driessche, Isabel, Skirtach, Andre G., Meijerink, Andries, Van Der Voort, Pascal, Condensed Matter and Interfaces, Sub Condensed Matter and Interfaces, Kaczmarek, Anna M., Suta, Markus, Rijckaert, Hannes, Abalymov, Anatolii, Van Driessche, Isabel, Skirtach, Andre G., Meijerink, Andries, and Van Der Voort, Pascal

Published
2020

14. Visible and NIR Upconverting Er3+–Yb3+ Luminescent Nanorattles and Other Hybrid PMO-Inorganic Structures for In Vivo Nanothermometry

Author

Condensed Matter and Interfaces, Sub Condensed Matter and Interfaces, Kaczmarek, Anna M., Suta, Markus, Rijckaert, Hannes, Abalymov, Anatolii, Van Driessche, Isabel, Skirtach, Andre G., Meijerink, Andries, Van Der Voort, Pascal, Condensed Matter and Interfaces, Sub Condensed Matter and Interfaces, Kaczmarek, Anna M., Suta, Markus, Rijckaert, Hannes, Abalymov, Anatolii, Van Driessche, Isabel, Skirtach, Andre G., Meijerink, Andries, and Van Der Voort, Pascal

Published
2020

15. Enhancement of biomimetic enzymatic mineralization of gellan gum polysaccharide hydrogels by plant-derived gallotannins

Author

Douglas, Timothy E.L., Keppler, Julia K., Vandrovcová, Marta, Plencner, Martin, Beranová, Jana, Feuereisen, Michelle, Parakhonskiy, Bogdan V., Svenskaya, Yulia, Atkin, Vsevolod, Ivanova, Anna, Ricquier, Patrick, Balcaen, Lieve, Vanhaecke, Frank, Schieber, Andreas, Bačáková, Lucie, Skirtach, Andre G., Douglas, Timothy E.L., Keppler, Julia K., Vandrovcová, Marta, Plencner, Martin, Beranová, Jana, Feuereisen, Michelle, Parakhonskiy, Bogdan V., Svenskaya, Yulia, Atkin, Vsevolod, Ivanova, Anna, Ricquier, Patrick, Balcaen, Lieve, Vanhaecke, Frank, Schieber, Andreas, Bačáková, Lucie, and Skirtach, Andre G.

Abstract

Mineralization of hydrogel biomaterials with calcium phosphate (CaP) is considered advantageous for bone regeneration. Mineralization can be both induced by the enzyme alkaline phosphatase (ALP) and promoted by calcium-binding biomolecules, such as plant-derived polyphenols. In this study, ALP-loaded gellan gum (GG) hydrogels were enriched with gallotannins, a subclass of polyphenols. Five preparations were compared, namely three tannic acids of differing molecular weight (MW), pentagalloyl glucose (PGG), and a gallotannin-rich extract from mango kernel (Mangifera indica L.). Certain gallotannin preparations promoted mineralization to a greater degree than others. The various gallotannin preparations bound differently to ALP and influenced the size of aggregates of ALP, which may be related to ability to promote mineralization. Human osteoblast-like Saos-2 cells grew in eluate from mineralized hydrogels. Gallotannin incorporation impeded cell growth on hydrogels and did not impart antibacterial activity. In conclusion, gallotannin incorporation aided mineralization but reduced cytocompatibility.

Published
2020

16. Enhancement of biomimetic enzymatic mineralization of gellan gum polysaccharide hydrogels by plant-derived gallotannins

Author

Douglas, Timothy, Keppler, Julia K., Vandrovcova, Marta, Plnencer, Martin, Beranova, Jana, Feuereisen, Michelle, Parakhonskiy, Bogdan V, Svenskaya, Yulia, Atkin, Vsevolod, Ivanova, Anna, Ricquier, Patrick, Balcaen, Lieve, Vanhaecke, Frank, Schieber, Andreas, Bacakova, Lucie, Skirtach, Andre G., Douglas, Timothy, Keppler, Julia K., Vandrovcova, Marta, Plnencer, Martin, Beranova, Jana, Feuereisen, Michelle, Parakhonskiy, Bogdan V, Svenskaya, Yulia, Atkin, Vsevolod, Ivanova, Anna, Ricquier, Patrick, Balcaen, Lieve, Vanhaecke, Frank, Schieber, Andreas, Bacakova, Lucie, and Skirtach, Andre G.

Abstract

Mineralization of hydrogel biomaterials with calcium phosphate (CaP) is considered advantageous for bone regeneration. Mineralization can be both induced by the enzyme alkaline phosphatase (ALP) and promoted by calcium-binding biomolecules, such as plant-derived polyphenols. In this study, ALP-loaded gellan gum (GG) hydrogels were enriched with gallotannins, a subclass of polyphenols. Five preparations were compared, namely three tannic acids of differing molecular weight (MW), pentagalloyl glucose (PGG), and a gallotannin-rich extract from mango kernel (Mangifera indica L.). Certain gallotannin preparations promoted mineralization to a greater degree than others. The various gallotannin preparations bound differently to ALP and influenced the size of aggregates of ALP, which may be related to ability to promote mineralization. Human osteoblast-like Saos-2 cells grew in eluate from mineralized hydrogels. Gallotannin incorporation impeded cell growth on hydrogels and did not impart antibacterial activity. In conclusion, gallotannin incorporation aided mineralization but reduced cytocompatibility.

Published
2020

17. Phenolic plant extract enrichment of enzymatically mineralized hydrogels

Author

Douglas, Timothy, Lopez-Heredia, Marco, Pulczynska, Aleksandra, Łapa, Agata, Pietryga, Krzysztof, Schaubroeck, David, Santos, Sonia, Pais, Adriana, Brackman, Gilles, De Schamphelaere, Karel, Samal, Sangram Keshari, Keppler, Julia K., Bauer, Jonas, Chai, Feng, Blanchemain, Nicolas, Coenye, Tom, Pamula, Elzbieta, Skirtach, Andre G., Douglas, Timothy, Lopez-Heredia, Marco, Pulczynska, Aleksandra, Łapa, Agata, Pietryga, Krzysztof, Schaubroeck, David, Santos, Sonia, Pais, Adriana, Brackman, Gilles, De Schamphelaere, Karel, Samal, Sangram Keshari, Keppler, Julia K., Bauer, Jonas, Chai, Feng, Blanchemain, Nicolas, Coenye, Tom, Pamula, Elzbieta, and Skirtach, Andre G.

Abstract

Hydrogel mineralization with calcium phosphate (CaP) and antibacterial activity are desirable for applications in bone regeneration. Mineralization with CaP can be induced using the enzyme alkaline phosphatase (ALP), responsible for CaP formation in bone tissue. Incorporation of polyphenols, plant-derived bactericidal molecules, was hypothesized to provide antibacterial activity and enhance ALP-induced mineralization. Three phenolic rich plant extracts from: (i) green tea, rich in epigallocatechin gallate (EGCG) (herafter referred to as EGCG-rich extract); (ii) pine bark and (iii) rosemary were added to gellan gum (GG) hydrogels and subsequently mineralized using ALP. The phenolic composition of the three extracts used were analyzed by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MSn). EGCG-rich extract showed the highest content of phenolic compounds and promoted the highest CaP formation as corroborated by dry mass percentage meassurements and ICP-OES de-termination of mass of elemental Ca and P. All three extracts alone exhibited antibacterial activity in the following order EGCG-rich > PI > RO, respectively. However, extract-loaded and mineralized GG hydro-gels did not exhibit appreciable antibacterial activity by diffusion test. In conclusion, only the EGCG-rich extract promotes ALP-mediated mineralization.

Published
2019

18. Hierarchy of hybrid materials – the place of inorganics-in-organics in it, their composition and applications

Author

Saveleva, Mariia, Eftekhari, Karaneh, Abalymov, Anatoly, Douglas, Timothy Edward Lim, Volodkin, Dmitry, Parakhonskiy, Bogdan V, Skirtach, Andre G., Saveleva, Mariia, Eftekhari, Karaneh, Abalymov, Anatoly, Douglas, Timothy Edward Lim, Volodkin, Dmitry, Parakhonskiy, Bogdan V, and Skirtach, Andre G.

Abstract

Hybrid materials, or hybrids incorporating both organic and inorganic constituents, are emerging as a very potent and promising class of materials due to the diverse, but complementary nature of the properties inherent of these different classes of materials. The complementarity leads to a perfect synergy of properties of desired material and eventually an end-product. The diversity of resultant properties and materials used in the construction of hybrids, leads to a very broad range of application areas generated by engaging very different research communities. We provide here a general classification of hybrid materials, wherein organics–in-inorganics (inorganic materials modified by organic moieties) are distinguished from inorganics–in–organics (organic materials or matrices modified by inorganic constituents). In the former area, the surface functionalization of colloids is distinguished as a stand-alone sub-area. The latter area—functionalization of organic materials by inorganic additives—is the focus of the current review. Inorganic constituents, often in the form of small particles or structures, are made of minerals, clays, semiconductors, metals, carbons, and ceramics. They are shown to be incorporated into organic matrices, which can be distinguished as two classes: chemical and biological. Chemical organic matrices include coatings, vehicles and capsules assembled into: hydrogels, layer-by-layer assembly, polymer brushes, block co-polymers and other assemblies. Biological organic matrices encompass bio-molecules (lipids, polysaccharides, proteins and enzymes, and nucleic acids) as well as higher level organisms: cells, bacteria, and microorganisms. In addition to providing details of the above classification and analysis of the composition of hybrids, we also highlight some antagonistic yin-&-yang properties of organic and inorganic materials, review applications and provide an outlook to emerging trends.

Published
2019

19. Pectin-bioactive glass self-gelling, injectable composites with high antibacterial activity

Author

Douglas, Timothy Edward Lim, Dziadek, Michal, Schietse, Josefien, Boone, Matthieu, Declercq, Heidi, Coenye, Tom, Vanhoorne, Valerie, Vervaet, Chris, Balcaen, Lieve, Buchweitz, Maria, Vanhaecke, Frank, Van Assche, Frederic, Cholewa-Kowalska, Katarzyna, Skirtach, Andre G., Douglas, Timothy Edward Lim, Dziadek, Michal, Schietse, Josefien, Boone, Matthieu, Declercq, Heidi, Coenye, Tom, Vanhoorne, Valerie, Vervaet, Chris, Balcaen, Lieve, Buchweitz, Maria, Vanhaecke, Frank, Van Assche, Frederic, Cholewa-Kowalska, Katarzyna, and Skirtach, Andre G.

Abstract

The present work focuses on the development of novel injectable, self-gelling composite hydrogels based on two types of low esterified amidated pectins from citrus peels and apple pomace. Sol-gelderived, calcium-rich bioactive glass (BG) fillers in a particle form are applied as delivery vehicles for the release of Ca2+ ions to induce internal gelation of pectins. Composites were prepared by a relatively simple mixing technique, using 20% w/v BG particles of two different sizes (2.5 and <45 µm). Smaller particles accelerated pectin gelation slightly faster than bigger ones, which appears to result from the higher rate of Ca2+ ion release. µCT showed inhomogeneous distribution of the BG particles within the hydrogels. All composite hydrogels exhibited strong antibacterial activity against methicilin-resistant Staphylococcus aureus. The mineralization process of pectin-BG composite hydrogels occurred upon incubation in simulated body fluid for 28 days. In vitro studies demonstrated cytocompatibility of composite hydrogels with MC3T3-E1 osteoblastic cells.

Published
2019

20. Phenolic plant extract enrichment of enzymatically mineralized hydrogels

Author

Douglas, Timothy, Lopez-Heredia, Marco, Pulczynska, Aleksandra, Łapa, Agata, Pietryga, Krzysztof, Schaubroeck, David, Santos, Sonia, Pais, Adriana, Brackman, Gilles, De Schamphelaere, Karel, Samal, Sangram Keshari, Keppler, Julia K., Bauer, Jonas, Chai, Feng, Blanchemain, Nicolas, Coenye, Tom, Pamula, Elzbieta, Skirtach, Andre G., Douglas, Timothy, Lopez-Heredia, Marco, Pulczynska, Aleksandra, Łapa, Agata, Pietryga, Krzysztof, Schaubroeck, David, Santos, Sonia, Pais, Adriana, Brackman, Gilles, De Schamphelaere, Karel, Samal, Sangram Keshari, Keppler, Julia K., Bauer, Jonas, Chai, Feng, Blanchemain, Nicolas, Coenye, Tom, Pamula, Elzbieta, and Skirtach, Andre G.

Abstract

Hydrogel mineralization with calcium phosphate (CaP) and antibacterial activity are desirable for applications in bone regeneration. Mineralization with CaP can be induced using the enzyme alkaline phosphatase (ALP), responsible for CaP formation in bone tissue. Incorporation of polyphenols, plant-derived bactericidal molecules, was hypothesized to provide antibacterial activity and enhance ALP-induced mineralization. Three phenolic rich plant extracts from: (i) green tea, rich in epigallocatechin gallate (EGCG) (herafter referred to as EGCG-rich extract); (ii) pine bark and (iii) rosemary were added to gellan gum (GG) hydrogels and subsequently mineralized using ALP. The phenolic composition of the three extracts used were analyzed by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MSn). EGCG-rich extract showed the highest content of phenolic compounds and promoted the highest CaP formation as corroborated by dry mass percentage meassurements and ICP-OES de-termination of mass of elemental Ca and P. All three extracts alone exhibited antibacterial activity in the following order EGCG-rich > PI > RO, respectively. However, extract-loaded and mineralized GG hydro-gels did not exhibit appreciable antibacterial activity by diffusion test. In conclusion, only the EGCG-rich extract promotes ALP-mediated mineralization.

Published
2019

21. Hierarchy of hybrid materials – the place of inorganics-in-organics in it, their composition and applications

Author

Saveleva, Mariia, Eftekhari, Karaneh, Abalymov, Anatoly, Douglas, Timothy Edward Lim, Volodkin, Dmitry, Parakhonskiy, Bogdan V, Skirtach, Andre G., Saveleva, Mariia, Eftekhari, Karaneh, Abalymov, Anatoly, Douglas, Timothy Edward Lim, Volodkin, Dmitry, Parakhonskiy, Bogdan V, and Skirtach, Andre G.

Abstract

Hybrid materials, or hybrids incorporating both organic and inorganic constituents, are emerging as a very potent and promising class of materials due to the diverse, but complementary nature of the properties inherent of these different classes of materials. The complementarity leads to a perfect synergy of properties of desired material and eventually an end-product. The diversity of resultant properties and materials used in the construction of hybrids, leads to a very broad range of application areas generated by engaging very different research communities. We provide here a general classification of hybrid materials, wherein organics–in-inorganics (inorganic materials modified by organic moieties) are distinguished from inorganics–in–organics (organic materials or matrices modified by inorganic constituents). In the former area, the surface functionalization of colloids is distinguished as a stand-alone sub-area. The latter area—functionalization of organic materials by inorganic additives—is the focus of the current review. Inorganic constituents, often in the form of small particles or structures, are made of minerals, clays, semiconductors, metals, carbons, and ceramics. They are shown to be incorporated into organic matrices, which can be distinguished as two classes: chemical and biological. Chemical organic matrices include coatings, vehicles and capsules assembled into: hydrogels, layer-by-layer assembly, polymer brushes, block co-polymers and other assemblies. Biological organic matrices encompass bio-molecules (lipids, polysaccharides, proteins and enzymes, and nucleic acids) as well as higher level organisms: cells, bacteria, and microorganisms. In addition to providing details of the above classification and analysis of the composition of hybrids, we also highlight some antagonistic yin-&-yang properties of organic and inorganic materials, review applications and provide an outlook to emerging trends.

Published
2019

22. Pectin-bioactive glass self-gelling, injectable composites with high antibacterial activity

Author

Douglas, Timothy Edward Lim, Dziadek, Michal, Schietse, Josefien, Boone, Matthieu, Declercq, Heidi, Coenye, Tom, Vanhoorne, Valerie, Vervaet, Chris, Balcaen, Lieve, Buchweitz, Maria, Vanhaecke, Frank, Van Assche, Frederic, Cholewa-Kowalska, Katarzyna, Skirtach, Andre G., Douglas, Timothy Edward Lim, Dziadek, Michal, Schietse, Josefien, Boone, Matthieu, Declercq, Heidi, Coenye, Tom, Vanhoorne, Valerie, Vervaet, Chris, Balcaen, Lieve, Buchweitz, Maria, Vanhaecke, Frank, Van Assche, Frederic, Cholewa-Kowalska, Katarzyna, and Skirtach, Andre G.

Abstract

The present work focuses on the development of novel injectable, self-gelling composite hydrogels based on two types of low esterified amidated pectins from citrus peels and apple pomace. Sol-gelderived, calcium-rich bioactive glass (BG) fillers in a particle form are applied as delivery vehicles for the release of Ca2+ ions to induce internal gelation of pectins. Composites were prepared by a relatively simple mixing technique, using 20% w/v BG particles of two different sizes (2.5 and <45 µm). Smaller particles accelerated pectin gelation slightly faster than bigger ones, which appears to result from the higher rate of Ca2+ ion release. µCT showed inhomogeneous distribution of the BG particles within the hydrogels. All composite hydrogels exhibited strong antibacterial activity against methicilin-resistant Staphylococcus aureus. The mineralization process of pectin-BG composite hydrogels occurred upon incubation in simulated body fluid for 28 days. In vitro studies demonstrated cytocompatibility of composite hydrogels with MC3T3-E1 osteoblastic cells.

Published
2019

23. ANN prediction of corrosion behaviour of uncoated and biopolymers coated cp-Titanium substrates

Author

Kumari, Suman, Tiyyagura, Hanuma Reddy, Douglas, Timothy E.L., Mohammed, Elbeshary A.A., Adriaens, Annemie, Fuchs-Godec, Regina, Mohan, M.K., Skirtach, Andre G., Kumari, Suman, Tiyyagura, Hanuma Reddy, Douglas, Timothy E.L., Mohammed, Elbeshary A.A., Adriaens, Annemie, Fuchs-Godec, Regina, Mohan, M.K., and Skirtach, Andre G.

Abstract

The present study focuses on biopolymer surface modification of cp-Titanium with Chitosan, Gelatin, and Sodium Alginate. The biopolymers were spin coated onto a cp-Titanium substrate and further subjected to Electrochemical Impedance Spectroscopic (EIS) characterization. Artificial Neural Network (ANN) was developed to predict the Open Circuit Potential (OCP) values and Nyquist plot for bare and biopolymer coated cp-Titanium substrate. The experimental data obtained was utilized for ANN training. Two input parameters, i.e., substrate condition (coated or uncoated) and time period were considered to predict the OCP values. Backpropagation Levenberg-Marquardt training algorithm was utilized in order to train ANN and to fit the model. For Nyquist plot, the network was trained to predict the imaginary impedance based on real impedance as a function of immersion periods using the Back Propagation Bayesian algorithm. The biopolymer coated cp-Titanium substrate shows the enhanced corrosion resistance compared to uncoated substrates. The ANN model exhibits excellent comparison with the experimental results in both the cases indicating that the developed model is very accurate and efficiently predicts the OCP values and Nyquist plot.

Published
2018

24. Mineralization of gellan gum hydrogels with calcium and magnesium carbonates by alternate soaking for bone regeneration applications

Author

Lopez-Heredia, Marco, Lapa, Agata, Reczynska, Katarzyna, Pietryga, Krzysztof, Balcaen, Lieve, Mendes, Ana, Schaubroeck, David, Van der Voort, Pascal, Dokupil, Agnieszka, Plis, Agnieszka, Stevens, Chris, Parakhonskiy, Bogdan, Samal, Sangram, Vanhaecke, Frank, Chai, Feng, Chronakis, Ioannis, Blanchemain, Nicolas, Pamula, Elzbieta, Skirtach, Andre G., Douglas, Timothy Edward Lim, Lopez-Heredia, Marco, Lapa, Agata, Reczynska, Katarzyna, Pietryga, Krzysztof, Balcaen, Lieve, Mendes, Ana, Schaubroeck, David, Van der Voort, Pascal, Dokupil, Agnieszka, Plis, Agnieszka, Stevens, Chris, Parakhonskiy, Bogdan, Samal, Sangram, Vanhaecke, Frank, Chai, Feng, Chronakis, Ioannis, Blanchemain, Nicolas, Pamula, Elzbieta, Skirtach, Andre G., and Douglas, Timothy Edward Lim

Abstract

Mineralization of hydrogels is desirable prior to applications in bone regeneration. CaCO3 is a widely used bone regeneration material and Mg, when used as a component of calcium phosphate biomaterials, has promoted bone‐forming cell adhesion and proliferation and bone regeneration. In this study, gellan gum (GG) hydrogels were mineralized with carbonates containing different amounts of calcium (Ca) and magnesium (Mg) by alternate soaking in, firstly, a calcium and/or magnesium ion solution and, secondly, a carbonate ion solution. This alternate soaking cycle was repeated five times. Five different calcium and/or magnesium ion solutions, containing different molar ratios of Ca to Mg ranging from Mg‐free to Ca‐free were compared. Carbonate mineral formed in all sample groups subjected to the Ca:Mg elemental ratio in the carbonate mineral formed was higher than in the respective mineralizing solution. Mineral formed in the absence of Mg was predominantly CaCO3 in the form of a mixture of calcite and vaterite. Increasing the Mg content in the mineral formed led to the formation of magnesian calcite, decreased the total amount of the mineral formed and its crystallinity. Hydrogel mineralization and increasing Mg content in mineral formed did not obviously improve proliferation of MC3T3‐E1 osteoblast‐like cells or differentiation after 7 days.

Published
2018

25. Phytase-mediated enzymatic mineralization of chitosan-enriched hydrogels

Author

Lišková, Jana, Douglas, Timothy E.L., Wijnants, Robbe, Samal, Sangram Keshari, Mendes, Ana C., Chronakis, Ioannis, Bačáková, Lucie, Skirtach, Andre G., Lišková, Jana, Douglas, Timothy E.L., Wijnants, Robbe, Samal, Sangram Keshari, Mendes, Ana C., Chronakis, Ioannis, Bačáková, Lucie, and Skirtach, Andre G.

Abstract

Hydrogels mineralized with calcium phosphate (CaP) are increasingly popular bone regeneration biomaterials. Mineralization can be achieved by phosphatase enzyme incorporation and incubation in calcium glycerophosphate (CaGP). Gellan gum (GG) hydrogels containing the enzyme phytase and chitosan oligomer were mineralized in CaGP solution and characterized with human osteoblast-like MG63 cells and adipose tissue-derived stem cells (ADSC). Phytase induced CaP formation. Chitosan concentration determined mineralization extent and hydrogel mechanical reinforcement. Phytase-induced mineralization promoted MG63 adhesion and proliferation, especially in the presence of chitosan, and was non-toxic to MG63 cells (with and without chitosan). ADSC adhesion and proliferation were poor without mineralization. Chitosan did not affect ADSC osteogenic differentiation.

Published
2018

26. ANN prediction of corrosion behaviour of uncoated and biopolymers coated cp-Titanium substrates

Author

Kumari, Suman, Tiyyagura, Hanuma Reddy, Douglas, Timothy E.L., Mohammed, Elbeshary A.A., Adriaens, Annemie, Fuchs-Godec, Regina, Mohan, M.K., Skirtach, Andre G., Kumari, Suman, Tiyyagura, Hanuma Reddy, Douglas, Timothy E.L., Mohammed, Elbeshary A.A., Adriaens, Annemie, Fuchs-Godec, Regina, Mohan, M.K., and Skirtach, Andre G.

Abstract

The present study focuses on biopolymer surface modification of cp-Titanium with Chitosan, Gelatin, and Sodium Alginate. The biopolymers were spin coated onto a cp-Titanium substrate and further subjected to Electrochemical Impedance Spectroscopic (EIS) characterization. Artificial Neural Network (ANN) was developed to predict the Open Circuit Potential (OCP) values and Nyquist plot for bare and biopolymer coated cp-Titanium substrate. The experimental data obtained was utilized for ANN training. Two input parameters, i.e., substrate condition (coated or uncoated) and time period were considered to predict the OCP values. Backpropagation Levenberg-Marquardt training algorithm was utilized in order to train ANN and to fit the model. For Nyquist plot, the network was trained to predict the imaginary impedance based on real impedance as a function of immersion periods using the Back Propagation Bayesian algorithm. The biopolymer coated cp-Titanium substrate shows the enhanced corrosion resistance compared to uncoated substrates. The ANN model exhibits excellent comparison with the experimental results in both the cases indicating that the developed model is very accurate and efficiently predicts the OCP values and Nyquist plot.

Published
2018

27. Mineralization of gellan gum hydrogels with calcium and magnesium carbonates by alternate soaking for bone regeneration applications

Author

Lopez-Heredia, Marco, Lapa, Agata, Reczynska, Katarzyna, Pietryga, Krzysztof, Balcaen, Lieve, Mendes, Ana, Schaubroeck, David, Van der Voort, Pascal, Dokupil, Agnieszka, Plis, Agnieszka, Stevens, Chris, Parakhonskiy, Bogdan, Samal, Sangram, Vanhaecke, Frank, Chai, Feng, Chronakis, Ioannis, Blanchemain, Nicolas, Pamula, Elzbieta, Skirtach, Andre G., Douglas, Timothy Edward Lim, Lopez-Heredia, Marco, Lapa, Agata, Reczynska, Katarzyna, Pietryga, Krzysztof, Balcaen, Lieve, Mendes, Ana, Schaubroeck, David, Van der Voort, Pascal, Dokupil, Agnieszka, Plis, Agnieszka, Stevens, Chris, Parakhonskiy, Bogdan, Samal, Sangram, Vanhaecke, Frank, Chai, Feng, Chronakis, Ioannis, Blanchemain, Nicolas, Pamula, Elzbieta, Skirtach, Andre G., and Douglas, Timothy Edward Lim

Abstract

Mineralization of hydrogels is desirable prior to applications in bone regeneration. CaCO3 is a widely used bone regeneration material and Mg, when used as a component of calcium phosphate biomaterials, has promoted bone‐forming cell adhesion and proliferation and bone regeneration. In this study, gellan gum (GG) hydrogels were mineralized with carbonates containing different amounts of calcium (Ca) and magnesium (Mg) by alternate soaking in, firstly, a calcium and/or magnesium ion solution and, secondly, a carbonate ion solution. This alternate soaking cycle was repeated five times. Five different calcium and/or magnesium ion solutions, containing different molar ratios of Ca to Mg ranging from Mg‐free to Ca‐free were compared. Carbonate mineral formed in all sample groups subjected to the Ca:Mg elemental ratio in the carbonate mineral formed was higher than in the respective mineralizing solution. Mineral formed in the absence of Mg was predominantly CaCO3 in the form of a mixture of calcite and vaterite. Increasing the Mg content in the mineral formed led to the formation of magnesian calcite, decreased the total amount of the mineral formed and its crystallinity. Hydrogel mineralization and increasing Mg content in mineral formed did not obviously improve proliferation of MC3T3‐E1 osteoblast‐like cells or differentiation after 7 days.

Published
2018

28. Phytase-mediated enzymatic mineralization of chitosan-enriched hydrogels

Author

Lišková, Jana, Douglas, Timothy E.L., Wijnants, Robbe, Samal, Sangram Keshari, Mendes, Ana C., Chronakis, Ioannis, Bačáková, Lucie, Skirtach, Andre G., Lišková, Jana, Douglas, Timothy E.L., Wijnants, Robbe, Samal, Sangram Keshari, Mendes, Ana C., Chronakis, Ioannis, Bačáková, Lucie, and Skirtach, Andre G.

Abstract

Hydrogels mineralized with calcium phosphate (CaP) are increasingly popular bone regeneration biomaterials. Mineralization can be achieved by phosphatase enzyme incorporation and incubation in calcium glycerophosphate (CaGP). Gellan gum (GG) hydrogels containing the enzyme phytase and chitosan oligomer were mineralized in CaGP solution and characterized with human osteoblast-like MG63 cells and adipose tissue-derived stem cells (ADSC). Phytase induced CaP formation. Chitosan concentration determined mineralization extent and hydrogel mechanical reinforcement. Phytase-induced mineralization promoted MG63 adhesion and proliferation, especially in the presence of chitosan, and was non-toxic to MG63 cells (with and without chitosan). ADSC adhesion and proliferation were poor without mineralization. Chitosan did not affect ADSC osteogenic differentiation.

Published
2018

29. Mineralization of gellan gum hydrogels with calcium and magnesium carbonates by alternate soaking in solutions of calcium/magnesium and carbonate ion solutions

Author

Lopez-Heredia, Marco A, Łapa, Agata, Reczyńska, Katarzyna, Pietryga, Krzysztof, Balcaen, Lieve, Mendes, Ana Carina Loureiro, Schaubroeck, David, Van Der Voort, Pascal, Dokupil, Agnieszka, Plis, Agnieszka, Stevens, Chris V, Parakhonskiy, Bogdan V, Samal, Sangram Keshari, Vanhaecke, Frank, Chai, Feng, Chronakis, Ioannis S., Blanchemain, Nicolas, Pamuła, Elżbieta, Skirtach, Andre G, Douglas, Timothy E L, Lopez-Heredia, Marco A, Łapa, Agata, Reczyńska, Katarzyna, Pietryga, Krzysztof, Balcaen, Lieve, Mendes, Ana Carina Loureiro, Schaubroeck, David, Van Der Voort, Pascal, Dokupil, Agnieszka, Plis, Agnieszka, Stevens, Chris V, Parakhonskiy, Bogdan V, Samal, Sangram Keshari, Vanhaecke, Frank, Chai, Feng, Chronakis, Ioannis S., Blanchemain, Nicolas, Pamuła, Elżbieta, Skirtach, Andre G, and Douglas, Timothy E L

Abstract

Mineralization of hydrogels is desirable prior to applications in bone regeneration. CaCO3 is a widely used bone regeneration material and Mg, when used as a component of calcium phosphate biomaterials, has promoted bone-forming cell adhesion and proliferation and bone regeneration. In this study, gellan gum (GG) hydrogels were mineralized with carbonates containing different amounts of calcium (Ca) and magnesium (Mg) by alternate soaking in, firstly, a calcium and/or magnesium ion solution and, secondly, a carbonate ion solution. This alternate soaking cycle was repeated five times. Five different calcium and/or magnesium ion solutions, containing different molar ratios of Ca to Mg ranging from Mg-free to Ca-free were compared. Carbonate mineral formed in all sample groups subjected to the Ca:Mg elemental ratio in the carbonate mineral formed was higher than in the respective mineralizing solution. Mineral formed in the absence of Mg was predominantly CaCO3 in the form of a mixture of calcite and vaterite. Increasing the Mg content in the mineral formed led to the formation of magnesian calcite, decreased the total amount of the mineral formed and its crystallinity. Hydrogel mineralization and increasing Mg content in mineral formed did not obviously improve proliferation of MC3T3-E1 osteoblast-like cells or differentiation after 7 days.

Published
2018

30. Diverse Applications of Nanomedicine.

Author

Pelaz, Beatriz, Pelaz, Beatriz, Alexiou, Christoph, Alvarez-Puebla, Ramon A, Alves, Frauke, Andrews, Anne M, Ashraf, Sumaira, Balogh, Lajos P, Ballerini, Laura, Bestetti, Alessandra, Brendel, Cornelia, Bosi, Susanna, Carril, Monica, Chan, Warren CW, Chen, Chunying, Chen, Xiaodong, Chen, Xiaoyuan, Cheng, Zhen, Cui, Daxiang, Du, Jianzhong, Dullin, Christian, Escudero, Alberto, Feliu, Neus, Gao, Mingyuan, George, Michael, Gogotsi, Yury, Grünweller, Arnold, Gu, Zhongwei, Halas, Naomi J, Hampp, Norbert, Hartmann, Roland K, Hersam, Mark C, Hunziker, Patrick, Jian, Ji, Jiang, Xingyu, Jungebluth, Philipp, Kadhiresan, Pranav, Kataoka, Kazunori, Khademhosseini, Ali, Kopeček, Jindřich, Kotov, Nicholas A, Krug, Harald F, Lee, Dong Soo, Lehr, Claus-Michael, Leong, Kam W, Liang, Xing-Jie, Ling Lim, Mei, Liz-Marzán, Luis M, Ma, Xiaowei, Macchiarini, Paolo, Meng, Huan, Möhwald, Helmuth, Mulvaney, Paul, Nel, Andre E, Nie, Shuming, Nordlander, Peter, Okano, Teruo, Oliveira, Jose, Park, Tai Hyun, Penner, Reginald M, Prato, Maurizio, Puntes, Victor, Rotello, Vincent M, Samarakoon, Amila, Schaak, Raymond E, Shen, Youqing, Sjöqvist, Sebastian, Skirtach, Andre G, Soliman, Mahmoud G, Stevens, Molly M, Sung, Hsing-Wen, Tang, Ben Zhong, Tietze, Rainer, Udugama, Buddhisha N, VanEpps, J Scott, Weil, Tanja, Weiss, Paul S, Willner, Itamar, Wu, Yuzhou, Yang, Lily, Yue, Zhao, Zhang, Qian, Zhang, Qiang, Zhang, Xian-En, Zhao, Yuliang, Zhou, Xin, Parak, Wolfgang J, Pelaz, Beatriz, Pelaz, Beatriz, Alexiou, Christoph, Alvarez-Puebla, Ramon A, Alves, Frauke, Andrews, Anne M, Ashraf, Sumaira, Balogh, Lajos P, Ballerini, Laura, Bestetti, Alessandra, Brendel, Cornelia, Bosi, Susanna, Carril, Monica, Chan, Warren CW, Chen, Chunying, Chen, Xiaodong, Chen, Xiaoyuan, Cheng, Zhen, Cui, Daxiang, Du, Jianzhong, Dullin, Christian, Escudero, Alberto, Feliu, Neus, Gao, Mingyuan, George, Michael, Gogotsi, Yury, Grünweller, Arnold, Gu, Zhongwei, Halas, Naomi J, Hampp, Norbert, Hartmann, Roland K, Hersam, Mark C, Hunziker, Patrick, Jian, Ji, Jiang, Xingyu, Jungebluth, Philipp, Kadhiresan, Pranav, Kataoka, Kazunori, Khademhosseini, Ali, Kopeček, Jindřich, Kotov, Nicholas A, Krug, Harald F, Lee, Dong Soo, Lehr, Claus-Michael, Leong, Kam W, Liang, Xing-Jie, Ling Lim, Mei, Liz-Marzán, Luis M, Ma, Xiaowei, Macchiarini, Paolo, Meng, Huan, Möhwald, Helmuth, Mulvaney, Paul, Nel, Andre E, Nie, Shuming, Nordlander, Peter, Okano, Teruo, Oliveira, Jose, Park, Tai Hyun, Penner, Reginald M, Prato, Maurizio, Puntes, Victor, Rotello, Vincent M, Samarakoon, Amila, Schaak, Raymond E, Shen, Youqing, Sjöqvist, Sebastian, Skirtach, Andre G, Soliman, Mahmoud G, Stevens, Molly M, Sung, Hsing-Wen, Tang, Ben Zhong, Tietze, Rainer, Udugama, Buddhisha N, VanEpps, J Scott, Weil, Tanja, Weiss, Paul S, Willner, Itamar, Wu, Yuzhou, Yang, Lily, Yue, Zhao, Zhang, Qian, Zhang, Qiang, Zhang, Xian-En, Zhao, Yuliang, Zhou, Xin, and Parak, Wolfgang J

Abstract

The design and use of materials in the nanoscale size range for addressing medical and health-related issues continues to receive increasing interest. Research in nanomedicine spans a multitude of areas, including drug delivery, vaccine development, antibacterial, diagnosis and imaging tools, wearable devices, implants, high-throughput screening platforms, etc. using biological, nonbiological, biomimetic, or hybrid materials. Many of these developments are starting to be translated into viable clinical products. Here, we provide an overview of recent developments in nanomedicine and highlight the current challenges and upcoming opportunities for the field and translation to the clinic.

Published
2017

31. Titanium surface functionalization with coatings of chitosan and polyphenol-rich plant extracts

Author

Douglas, Timothy E.L., Kumari, Suman, Dziadek, Kinga, Dziadek, Michal, Abalymov, Anatoly, Cools, Pieter, Brackman, Gilles, Coenye, Tom, Morent, Rino, Mohan, M.K., Skirtach, Andre G., Douglas, Timothy E.L., Kumari, Suman, Dziadek, Kinga, Dziadek, Michal, Abalymov, Anatoly, Cools, Pieter, Brackman, Gilles, Coenye, Tom, Morent, Rino, Mohan, M.K., and Skirtach, Andre G.

Abstract

Coating biomedical implant surfaces with biopolymers is an easy and inexpensive way to impart functionalities. Numerous biocompatible biopolymers, including cationic crustacean-derived chitosans, have been used. Here, substrates of Titanium (Ti), commonly used for bone contact applications, were coated with chitosan and one of three polyphenol-rich plant extracts (PPrPE) and characterized physicochemically. Hela cell adhesion and growth of methicillin-resistant Staphylococcus aureus (MRSA) were studied. Chitosan and PPrPE on surfaces were detected by FTIR and XPS. Chitosan coatings, both with and without PPrPE functionalization, did not inhibit MRSA growth and promoted Hela cell adhesion. The effect of PPrPE functionalization remained unclear.

Published
2017

32. Diverse Applications of Nanomedicine.

Author

Pelaz, Beatriz, Pelaz, Beatriz, Alexiou, Christoph, Alvarez-Puebla, Ramon A, Alves, Frauke, Andrews, Anne M, Ashraf, Sumaira, Balogh, Lajos P, Ballerini, Laura, Bestetti, Alessandra, Brendel, Cornelia, Bosi, Susanna, Carril, Monica, Chan, Warren CW, Chen, Chunying, Chen, Xiaodong, Chen, Xiaoyuan, Cheng, Zhen, Cui, Daxiang, Du, Jianzhong, Dullin, Christian, Escudero, Alberto, Feliu, Neus, Gao, Mingyuan, George, Michael, Gogotsi, Yury, Grünweller, Arnold, Gu, Zhongwei, Halas, Naomi J, Hampp, Norbert, Hartmann, Roland K, Hersam, Mark C, Hunziker, Patrick, Jian, Ji, Jiang, Xingyu, Jungebluth, Philipp, Kadhiresan, Pranav, Kataoka, Kazunori, Khademhosseini, Ali, Kopeček, Jindřich, Kotov, Nicholas A, Krug, Harald F, Lee, Dong Soo, Lehr, Claus-Michael, Leong, Kam W, Liang, Xing-Jie, Ling Lim, Mei, Liz-Marzán, Luis M, Ma, Xiaowei, Macchiarini, Paolo, Meng, Huan, Möhwald, Helmuth, Mulvaney, Paul, Nel, Andre E, Nie, Shuming, Nordlander, Peter, Okano, Teruo, Oliveira, Jose, Park, Tai Hyun, Penner, Reginald M, Prato, Maurizio, Puntes, Victor, Rotello, Vincent M, Samarakoon, Amila, Schaak, Raymond E, Shen, Youqing, Sjöqvist, Sebastian, Skirtach, Andre G, Soliman, Mahmoud G, Stevens, Molly M, Sung, Hsing-Wen, Tang, Ben Zhong, Tietze, Rainer, Udugama, Buddhisha N, VanEpps, J Scott, Weil, Tanja, Weiss, Paul S, Willner, Itamar, Wu, Yuzhou, Yang, Lily, Yue, Zhao, Zhang, Qian, Zhang, Qiang, Zhang, Xian-En, Zhao, Yuliang, Zhou, Xin, Parak, Wolfgang J, Pelaz, Beatriz, Pelaz, Beatriz, Alexiou, Christoph, Alvarez-Puebla, Ramon A, Alves, Frauke, Andrews, Anne M, Ashraf, Sumaira, Balogh, Lajos P, Ballerini, Laura, Bestetti, Alessandra, Brendel, Cornelia, Bosi, Susanna, Carril, Monica, Chan, Warren CW, Chen, Chunying, Chen, Xiaodong, Chen, Xiaoyuan, Cheng, Zhen, Cui, Daxiang, Du, Jianzhong, Dullin, Christian, Escudero, Alberto, Feliu, Neus, Gao, Mingyuan, George, Michael, Gogotsi, Yury, Grünweller, Arnold, Gu, Zhongwei, Halas, Naomi J, Hampp, Norbert, Hartmann, Roland K, Hersam, Mark C, Hunziker, Patrick, Jian, Ji, Jiang, Xingyu, Jungebluth, Philipp, Kadhiresan, Pranav, Kataoka, Kazunori, Khademhosseini, Ali, Kopeček, Jindřich, Kotov, Nicholas A, Krug, Harald F, Lee, Dong Soo, Lehr, Claus-Michael, Leong, Kam W, Liang, Xing-Jie, Ling Lim, Mei, Liz-Marzán, Luis M, Ma, Xiaowei, Macchiarini, Paolo, Meng, Huan, Möhwald, Helmuth, Mulvaney, Paul, Nel, Andre E, Nie, Shuming, Nordlander, Peter, Okano, Teruo, Oliveira, Jose, Park, Tai Hyun, Penner, Reginald M, Prato, Maurizio, Puntes, Victor, Rotello, Vincent M, Samarakoon, Amila, Schaak, Raymond E, Shen, Youqing, Sjöqvist, Sebastian, Skirtach, Andre G, Soliman, Mahmoud G, Stevens, Molly M, Sung, Hsing-Wen, Tang, Ben Zhong, Tietze, Rainer, Udugama, Buddhisha N, VanEpps, J Scott, Weil, Tanja, Weiss, Paul S, Willner, Itamar, Wu, Yuzhou, Yang, Lily, Yue, Zhao, Zhang, Qian, Zhang, Qiang, Zhang, Xian-En, Zhao, Yuliang, Zhou, Xin, and Parak, Wolfgang J

Abstract

The design and use of materials in the nanoscale size range for addressing medical and health-related issues continues to receive increasing interest. Research in nanomedicine spans a multitude of areas, including drug delivery, vaccine development, antibacterial, diagnosis and imaging tools, wearable devices, implants, high-throughput screening platforms, etc. using biological, nonbiological, biomimetic, or hybrid materials. Many of these developments are starting to be translated into viable clinical products. Here, we provide an overview of recent developments in nanomedicine and highlight the current challenges and upcoming opportunities for the field and translation to the clinic.

Published
2017

33. Diverse Applications of Nanomedicine

Author

German Academic Exchange Service, Chinese Academy of Sciences, National Natural Science Foundation of China, National Basic Research Program (China), European Commission, Ministerio de Economía y Competitividad (España), Generalitat de Catalunya, Swiss National Science Foundation, Julian Schwinger Foundation, Claude Leon Foundation, National Science Foundation (US), Canadian Institutes of Health Research, Natural Sciences and Engineering Research Council of Canada, Alexander von Humboldt Foundation, Lars Hierta Memorial Foundation, Eusko Jaurlaritza, Research Grants Council (Hong Kong), National Cancer Institute (US), Junta de Andalucía, Research Foundation - Flanders, German Research Foundation, Pelaz, Beatriz, Alexiou, Christoph, Álvarez-Puebla, Ramón, Alves, Frauke, Andrews, Anne M., Ashraf, Sumaira, Balogh, Lajos P., Ballerini, Laura, Bestetti, Alessandra, Brendel, Cornelia, Bosi, Susanna, Carril, Mónica, Chan, Warren C. W., Chen, Chunying, Chen, Xiaodong, Chen, Xiaoyuan, Cheng, Zhen, Cui, Daxiang, Du, Jianzhong, Dullin, Christian, Escudero, A., Feliu, Neus, Gao, Mingyuan, George, Michael, Gogotsi, Yury, Grünweller, Arnold, Gu, Zhongwei, Halas, Naomi J., Hampp, Norbert, Hartmann, Roland K., Hersam, Mark C., Hunziker, Patrick, Jian, Ji, Jiang, Xingyu, Jungebluth, Philipp, Kadhiresan, Pranav, Kataoka, Kazunori, Khademhosseini, Ali, Kopecek, Jindrich, Kotov, Nicholas A., Krug, Harald F., Lee, Dong Soo, Lehr, Claus-Michael, Leong, Kam W., Liang, Xing-Jie, Ling Lim, Mei, Liz-Marzán, Luis Manuel, Ma, Xiaowei, Macchiarini, Paolo, Meng, Huan, Möhwald, Helmuth, Mulvaney, Paul, Nel, Andre, E., Nie, Shuming, Nordlander, Peter, Okano, Teruo, Oliveira, José, Park, Tai Hyun, Penner, Reginald M., Prato, Maurizio, Puntes, Victor, Rotello, Vincent M., Samarakoon, Amila, Schaak, Raymond E., Shen, Youqing, Sjöqvist, Sebastian, Skirtach, Andre G., Soliman, Mahmoud G., Stevens, Molly M., Sung, Hsing-Wen, Zhong Tang, Ben, Tietze, Rainer, Udugama, Buddhisha N., VanEpps, J. Scott, Weil, Tanja, Weiss, Paul S., Willner, Itamar, Wu, Yuzhou, Yang, Lily, Yue, Zhao, Zhang, Qian, Zhang, Qiang, Zhang, Xian-En, Zhao, Yuliang, Zhou, Xin, Parak, Wolfgang J., German Academic Exchange Service, Chinese Academy of Sciences, National Natural Science Foundation of China, National Basic Research Program (China), European Commission, Ministerio de Economía y Competitividad (España), Generalitat de Catalunya, Swiss National Science Foundation, Julian Schwinger Foundation, Claude Leon Foundation, National Science Foundation (US), Canadian Institutes of Health Research, Natural Sciences and Engineering Research Council of Canada, Alexander von Humboldt Foundation, Lars Hierta Memorial Foundation, Eusko Jaurlaritza, Research Grants Council (Hong Kong), National Cancer Institute (US), Junta de Andalucía, Research Foundation - Flanders, German Research Foundation, Pelaz, Beatriz, Alexiou, Christoph, Álvarez-Puebla, Ramón, Alves, Frauke, Andrews, Anne M., Ashraf, Sumaira, Balogh, Lajos P., Ballerini, Laura, Bestetti, Alessandra, Brendel, Cornelia, Bosi, Susanna, Carril, Mónica, Chan, Warren C. W., Chen, Chunying, Chen, Xiaodong, Chen, Xiaoyuan, Cheng, Zhen, Cui, Daxiang, Du, Jianzhong, Dullin, Christian, Escudero, A., Feliu, Neus, Gao, Mingyuan, George, Michael, Gogotsi, Yury, Grünweller, Arnold, Gu, Zhongwei, Halas, Naomi J., Hampp, Norbert, Hartmann, Roland K., Hersam, Mark C., Hunziker, Patrick, Jian, Ji, Jiang, Xingyu, Jungebluth, Philipp, Kadhiresan, Pranav, Kataoka, Kazunori, Khademhosseini, Ali, Kopecek, Jindrich, Kotov, Nicholas A., Krug, Harald F., Lee, Dong Soo, Lehr, Claus-Michael, Leong, Kam W., Liang, Xing-Jie, Ling Lim, Mei, Liz-Marzán, Luis Manuel, Ma, Xiaowei, Macchiarini, Paolo, Meng, Huan, Möhwald, Helmuth, Mulvaney, Paul, Nel, Andre, E., Nie, Shuming, Nordlander, Peter, Okano, Teruo, Oliveira, José, Park, Tai Hyun, Penner, Reginald M., Prato, Maurizio, Puntes, Victor, Rotello, Vincent M., Samarakoon, Amila, Schaak, Raymond E., Shen, Youqing, Sjöqvist, Sebastian, Skirtach, Andre G., Soliman, Mahmoud G., Stevens, Molly M., Sung, Hsing-Wen, Zhong Tang, Ben, Tietze, Rainer, Udugama, Buddhisha N., VanEpps, J. Scott, Weil, Tanja, Weiss, Paul S., Willner, Itamar, Wu, Yuzhou, Yang, Lily, Yue, Zhao, Zhang, Qian, Zhang, Qiang, Zhang, Xian-En, Zhao, Yuliang, Zhou, Xin, and Parak, Wolfgang J.

Abstract

The design and use of materials in the nanoscale size range for addressing medical and health-related issues continues to receive increasing interest. Research in nanomedicine spans a multitude of areas, including drug delivery, vaccine development, antibacterial, diagnosis and imaging tools, wearable devices, implants, high-throughput screening platforms, etc. using biological, nonbiological, biomimetic, or hybrid materials. Many of these developments are starting to be translated into viable clinical products. Here, we provide an overview of recent developments in nanomedicine and highlight the current challenges and upcoming opportunities for the field and translation to the clinic.

Published
2017

34. Enzymatic, urease-mediated mineralization of gellan gum hydrogel with calcium carbonate, magnesium-enriched calcium carbonate and magnesium carbonate for bone regeneration applications

Author

Douglas, Timothy E L, Łapa, Agata, Samal, Sangram Keshari, Declercq, Heidi A., Schaubroeck, David, Mendes, Ana Carina Loureiro, der Voort, Pascal Van, Dokupil, Agnieszka, Plis, Agnieszka, De Schamphelaere, Karel, Chronakis, Ioannis S., Pamuła, Elżbieta, Skirtach, Andre G., Douglas, Timothy E L, Łapa, Agata, Samal, Sangram Keshari, Declercq, Heidi A., Schaubroeck, David, Mendes, Ana Carina Loureiro, der Voort, Pascal Van, Dokupil, Agnieszka, Plis, Agnieszka, De Schamphelaere, Karel, Chronakis, Ioannis S., Pamuła, Elżbieta, and Skirtach, Andre G.

Abstract

Mineralization of hydrogel biomaterials is considered desirable to improve their suitability as materials for bone regeneration. Calcium carbonate (CaCO3 ) has been successfully applied as a bone regeneration material, but hydrogel-CaCO3 composites have received less attention. Magnesium (Mg) has been used as a component of calcium phosphate biomaterials to stimulate bone-forming cell adhesion and proliferation and bone regeneration in vivo, but its effect as a component of carbonate-based biomaterials remains uninvestigated. In the present study, gellan gum (GG) hydrogels were mineralized enzymatically with CaCO3 , Mg-enriched CaCO3 and magnesium carbonate to generate composite biomaterials for bone regeneration. Hydrogels loaded with the enzyme urease were mineralized by incubation in mineralization media containing urea and different ratios of calcium and magnesium ions. Increasing the magnesium concentration decreased mineral crystallinity. At low magnesium concentrations calcite was formed, while at higher concentrations magnesian calcite was formed. Hydromagnesite (Mg5 (CO3 )4 (OH)2 .4H2 O) formed at high magnesium concentration in the absence of calcium. The amount of mineral formed and compressive strength decreased with increasing magnesium concentration in the mineralization medium. The calcium:magnesium elemental ratio in the mineral formed was higher than in the respective mineralization media. Mineralization of hydrogels with calcite or magnesian calcite promoted adhesion and growth of osteoblast-like cells. Hydrogels mineralized with hydromagnesite displayed higher cytotoxicity. In conclusion, enzymatic mineralization of GG hydrogels with CaCO3 in the form of calcite successfully reinforced hydrogels and promoted osteoblast-like cell adhesion and growth, but magnesium enrichment had no definitive positive effect. Copyright © 2017 John Wiley & Sons, Ltd.

Published
2017

35. Titanium surface functionalization with coatings of chitosan and polyphenol-rich plant extracts

Author

Douglas, Timothy E.L., Kumari, Suman, Dziadek, Kinga, Dziadek, Michal, Abalymov, Anatoly, Cools, Pieter, Brackman, Gilles, Coenye, Tom, Morent, Rino, Mohan, M.K., Skirtach, Andre G., Douglas, Timothy E.L., Kumari, Suman, Dziadek, Kinga, Dziadek, Michal, Abalymov, Anatoly, Cools, Pieter, Brackman, Gilles, Coenye, Tom, Morent, Rino, Mohan, M.K., and Skirtach, Andre G.

Abstract

Coating biomedical implant surfaces with biopolymers is an easy and inexpensive way to impart functionalities. Numerous biocompatible biopolymers, including cationic crustacean-derived chitosans, have been used. Here, substrates of Titanium (Ti), commonly used for bone contact applications, were coated with chitosan and one of three polyphenol-rich plant extracts (PPrPE) and characterized physicochemically. Hela cell adhesion and growth of methicillin-resistant Staphylococcus aureus (MRSA) were studied. Chitosan and PPrPE on surfaces were detected by FTIR and XPS. Chitosan coatings, both with and without PPrPE functionalization, did not inhibit MRSA growth and promoted Hela cell adhesion. The effect of PPrPE functionalization remained unclear.

Published
2017

36. Enzymatic, urease-mediated mineralization of gellan gum hydrogel with calcium carbonate, magnesium-enriched calcium carbonate and magnesium carbonate for bone regeneration applications

Author

Douglas, Timothy, Lapa, Agata, Samal, Sangram K., Declercq, Heidi A., Schaubroeck, David, Mendes, Ana Carina Loureiro, Van Der Voort, Pascal, Dokupil, Agnieszka, De Schamphelaere, Karel, Chronakis, Ioannis S., Pamula, Elzbieta, Skirtach, Andre G., Douglas, Timothy, Lapa, Agata, Samal, Sangram K., Declercq, Heidi A., Schaubroeck, David, Mendes, Ana Carina Loureiro, Van Der Voort, Pascal, Dokupil, Agnieszka, De Schamphelaere, Karel, Chronakis, Ioannis S., Pamula, Elzbieta, and Skirtach, Andre G.

Abstract

Introduction: Mineralization of hydrogel biomaterials is considered desirable to improve their suitability as materials for bone regeneration[1],[2]. Hydrogels have been most commonly mineralized with calcium phosphate (CaP), but hydrogel-CaCO3 composites have received less attention. Magnesium (Mg) has been added to CaP to stimulate cell adhesion and proliferation and bone regeneration in vivo, but its effect as a component of carbonate-based biomaterials remains uninvestigated. In this study, gellan gum (GG) hydrogels were mineralized enzymatically with (CaCO3), Mg-enriched CaCO3 and magnesium carbonate to generate composite biomaterials for bone regeneration. GG is an inexpensive, biotechnologically produced anionic polysaccharide, from which hydrogels for cartilage regeneration have been formed by crosslinking with divalent ions[3]. Methods: GG hydrogels were loaded with the enzyme urease by incubation in 5% (w/v) urease solution and mineralized for 5 days in five different media denoted as UA, UB, UC, UD and UE, which contained urea (0.17 M) and different concentrations of CaCl2 and MgCl2 (270:0, 202.5:67.5, 135:135, 67.5:202.5 and 0:250, respectively (mmol dm-3)). Discs were autoclaved and subjected to physiochemical, mechanical and cell biological characterization. Results: FTIR, SEM, TGA and XRD analysis revealed that increasing magnesium concentration decreased mineral crystallinity. At low magnesium concentrations calcite was formed, while at higher concentrations magnesian calcite was formed. Hydromagnesite formed at high magnesium concentration in the absence of calcium. Amount of mineral formed and compressive strength decreased with increasing magnesium concentration in the mineralization medium. ICP analysis revealed that Ca:Mg elemental ratio in the mineral formed was higher than in the respective mineralization media. Mineralization of hydrogels promoted adhesion and growth of osteoblast-like cells, which were supported best on min

Published
2016

37. Carbon Nanotubes on Polymeric Microcapsules: Free-Standing Structures and Point-Wise Laser Openings

Author

Department of Chemistry, University of Michigan, Ann Arbor, MI 48109 (USA), Faculty of Nano- and Biomedical Technologies, Saratov State University, Saratov, 410012 (Russia), Faculty of Nano- and Biomedical Technologies, Saratov State University, Saratov, 410012 (Russia) ; Department of Interfaces, Max-Planck Institute of Colloids and Interfaces, Golm/Potsdam, D14476 (Germany) ; Faculty of Nano- and Biomedical Technologies, Saratov State University, Saratov, 410012 (Russia)., Faculty of Nano- and Biomedical Technologies, Saratov State University, Saratov, 410012 (Russia) ; School of Engineering & Materials Science, Queen Mary University of London, Mile End Road, London, E1 4NS (UK), Department of Physics, Queen Mary University of London, Mile End Road, London, E1 4NS (UK), Faculty of Physics, Moscow State University, Moscow, 119899 (Russia) ; Institute of Nanotechnologies for Microelectronics, Leninsky Pr. 32a, Moscow 119991 (Russia), School of Engineering & Materials Science, Queen Mary University of London, Mile End Road, London, E1 4NS (UK), Department of Interfaces, Max-Planck Institute of Colloids and Interfaces, Golm/Potsdam, D14476 (Germany), Yashchenok, Alexey M., Bratashov, Daniil N., Gorin, Dmitry A., Lomova, Maria V., Pavlov, Anton M., Sapelkin, Andrei V., Shim, Bong Sup, Khomutov, Gennady B., Kotov, Nicholas A., Sukhorukov, Gleb B., Möhwald, Helmuth, Skirtach, Andre G., Department of Chemistry, University of Michigan, Ann Arbor, MI 48109 (USA), Faculty of Nano- and Biomedical Technologies, Saratov State University, Saratov, 410012 (Russia), Faculty of Nano- and Biomedical Technologies, Saratov State University, Saratov, 410012 (Russia) ; Department of Interfaces, Max-Planck Institute of Colloids and Interfaces, Golm/Potsdam, D14476 (Germany) ; Faculty of Nano- and Biomedical Technologies, Saratov State University, Saratov, 410012 (Russia)., Faculty of Nano- and Biomedical Technologies, Saratov State University, Saratov, 410012 (Russia) ; School of Engineering & Materials Science, Queen Mary University of London, Mile End Road, London, E1 4NS (UK), Department of Physics, Queen Mary University of London, Mile End Road, London, E1 4NS (UK), Faculty of Physics, Moscow State University, Moscow, 119899 (Russia) ; Institute of Nanotechnologies for Microelectronics, Leninsky Pr. 32a, Moscow 119991 (Russia), School of Engineering & Materials Science, Queen Mary University of London, Mile End Road, London, E1 4NS (UK), Department of Interfaces, Max-Planck Institute of Colloids and Interfaces, Golm/Potsdam, D14476 (Germany), Yashchenok, Alexey M., Bratashov, Daniil N., Gorin, Dmitry A., Lomova, Maria V., Pavlov, Anton M., Sapelkin, Andrei V., Shim, Bong Sup, Khomutov, Gennady B., Kotov, Nicholas A., Sukhorukov, Gleb B., Möhwald, Helmuth, and Skirtach, Andre G.

Abstract

Single-wall carbon nanotubes modified by anionic polyelectrolyte molecules are embedded into the shells of microcapsules. Carbon nanotubes serve as rigid rods in a softer polymeric capsule, which forms a free-standing shell upon treatment with glutaraldehyde and subsequent drying. The embedded carbon nanotubes exhibit a broad absorption in the UV–near-infrared part of the spectrum, and that allows point-wise activation and opening of the microcapsules by laser. Raman signal analysis shows changes of carbon-nanotube-specific lines after high-power laser irradiation, which is characteristic of the formation of disordered carbonlike structures. These polyelectrolyte/carbon nanotube composite capsules represent a novel light-addressable type of microcontainers.

Published
2010

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