Oxid grafenu (GO) je vhodný materiál pro přípravu elektricky vodivých hybridních částic a nanokompozitních materiálů pro biomedicínské aplikace. Zavádění kyslíkových funkčních skupin na povrch grafenu vede k povrchové funkcionalizaci, ale také ke snížení jeho elektrické vodivosti. K získání elektricky vodivých GO hybridních částic je možné využít techniku povrchově iniciované radikálové polymerace s přenosem atomu (SI-ATRP). V této práci byl GO připraven čtyřmi různými metodami (Brodieho, Staundemaierova, Hummersova a Tourova methoda) a následně modifikován a redukován pomocí SI-ATRP. Na povrch jednotlivých typů GO byly roubovány polymethylmethakrylát (PMMA) nebo poly(2-isopropenyl-2-oxazoline) (PiPOX), a tak byly připraveny dva typy GO polymerních hybridních částic, GO-PMMA and GO-PiPox. GO částice a jejich hybridy byly následně charakterizovány spektrálními a tepelnými metodami a nakonec byl zhodnocen vliv způsobu oxidace grafenu na biokompatibilitu a vodivost hybridních částic. Bylo ověřeno, že pomocí SI-ATRP je možné roubovat PMMA z každého typu GO a zároveň redukovat povrch GO. Test cytotoxicity ukázal, že metoda přípravy GO ovlivňuje cytotoxicitu výsledného materiálu. Modifikace pomocí PiPOX výrazně nemění biokompatibilitu částic a tyto GO hybridní částice mohou být použity pro biomedicínské aplikace.
Annotation in English
Graphene oxide (GO) is a suitable material for the preparation of electrically conductive hybrid particles and nanocomposite materials for biomedical applications. The functionalization of the graphene surface with oxygen-based groups increases the reactivity of the particles, but it also reduces their electrical conductivity. However, modification of the surface through surface-initiated atom transfer radical polymerization (SI-ATRP) can produce electrically conductive GO hybrid particles. Four different preparation methods were used to obtain GO in this work - Brodie, Staundemaier, Hummers, and Tours methods - and formed particles were modified and reduced with SI-ATRP. Thus Poly(Methyl Methacrylate) (PMMA) and Poly(2-isopropenyl-2-oxazoline) (PiPOX) were grafted from GO surface to obtain GO-PMMA and GO-PiPox, respectively. The sets of hybrids with varied electrical conductivity were prepared. Different analytical methods were used to characterize GO particles and their hybrids, and their electrical conductivity and the effect on the biocompatibility of hybrid particles were evaluated. It was verified that it is possible to graft PMMA from each type of GO while reducing the GO surface. The cytotoxicity assay showed that the preparation method affects the cytotoxicity of the resulting material. Modification with PiPOX does not significantly change the particles' biocompatibility; these GO hybrid particles could be used for biomedical applications.
Keywords
oxidace grafenu, SI-ATRP, biokompatibilita, elektrická vodivost GO, GO hybridní částice
Keywords in English
GO preparation methods, SI-ATRP, biocompatibility, the electrical conductivity of GO, GO hybrid particles
Length of the covering note
87
Language
CZ
Annotation
Oxid grafenu (GO) je vhodný materiál pro přípravu elektricky vodivých hybridních částic a nanokompozitních materiálů pro biomedicínské aplikace. Zavádění kyslíkových funkčních skupin na povrch grafenu vede k povrchové funkcionalizaci, ale také ke snížení jeho elektrické vodivosti. K získání elektricky vodivých GO hybridních částic je možné využít techniku povrchově iniciované radikálové polymerace s přenosem atomu (SI-ATRP). V této práci byl GO připraven čtyřmi různými metodami (Brodieho, Staundemaierova, Hummersova a Tourova methoda) a následně modifikován a redukován pomocí SI-ATRP. Na povrch jednotlivých typů GO byly roubovány polymethylmethakrylát (PMMA) nebo poly(2-isopropenyl-2-oxazoline) (PiPOX), a tak byly připraveny dva typy GO polymerních hybridních částic, GO-PMMA and GO-PiPox. GO částice a jejich hybridy byly následně charakterizovány spektrálními a tepelnými metodami a nakonec byl zhodnocen vliv způsobu oxidace grafenu na biokompatibilitu a vodivost hybridních částic. Bylo ověřeno, že pomocí SI-ATRP je možné roubovat PMMA z každého typu GO a zároveň redukovat povrch GO. Test cytotoxicity ukázal, že metoda přípravy GO ovlivňuje cytotoxicitu výsledného materiálu. Modifikace pomocí PiPOX výrazně nemění biokompatibilitu částic a tyto GO hybridní částice mohou být použity pro biomedicínské aplikace.
Annotation in English
Graphene oxide (GO) is a suitable material for the preparation of electrically conductive hybrid particles and nanocomposite materials for biomedical applications. The functionalization of the graphene surface with oxygen-based groups increases the reactivity of the particles, but it also reduces their electrical conductivity. However, modification of the surface through surface-initiated atom transfer radical polymerization (SI-ATRP) can produce electrically conductive GO hybrid particles. Four different preparation methods were used to obtain GO in this work - Brodie, Staundemaier, Hummers, and Tours methods - and formed particles were modified and reduced with SI-ATRP. Thus Poly(Methyl Methacrylate) (PMMA) and Poly(2-isopropenyl-2-oxazoline) (PiPOX) were grafted from GO surface to obtain GO-PMMA and GO-PiPox, respectively. The sets of hybrids with varied electrical conductivity were prepared. Different analytical methods were used to characterize GO particles and their hybrids, and their electrical conductivity and the effect on the biocompatibility of hybrid particles were evaluated. It was verified that it is possible to graft PMMA from each type of GO while reducing the GO surface. The cytotoxicity assay showed that the preparation method affects the cytotoxicity of the resulting material. Modification with PiPOX does not significantly change the particles' biocompatibility; these GO hybrid particles could be used for biomedical applications.
Keywords
oxidace grafenu, SI-ATRP, biokompatibilita, elektrická vodivost GO, GO hybridní částice
Keywords in English
GO preparation methods, SI-ATRP, biocompatibility, the electrical conductivity of GO, GO hybrid particles
Research Plan
The oxidation of graphene leads to its surface functionalization and decreasing of its electrical conductivity. The aim of this work will be the preparation of graphene oxide (GO) by different methods and checking its ability to restrain its electrical conductivity using catalytic system of surface initiated atom transfer radical polymerization (SI-ATRP). This GO will be modified by polymer chains of poly(methyl methacrylate) (PMMA) and poly(2-Isopropenyl-2-oxazoline) (PiPOx).
Theoretical part will be focused on oxidation of graphene and controlled radical polymerizations. It will also focus on the possibilities of preparing hybrid particles, especially using controlled radical polymerizations. It also outlines the use of these systems.
In the experimental part, graphene oxides will be prepared by selected methods. The ability to reduce them using the ligands of the SI-ATRP catalytic system will be verified. The initiator will be bound onto GO particles and polymerization by PMMA and PiPOX will be carried out. GO particles and their hybrids will be characterized by different spectral and thermal methods. Finally, their electrical conductivity and the effect on the biocompatibility of hybrid particles will be evaluated.
Research Plan
The oxidation of graphene leads to its surface functionalization and decreasing of its electrical conductivity. The aim of this work will be the preparation of graphene oxide (GO) by different methods and checking its ability to restrain its electrical conductivity using catalytic system of surface initiated atom transfer radical polymerization (SI-ATRP). This GO will be modified by polymer chains of poly(methyl methacrylate) (PMMA) and poly(2-Isopropenyl-2-oxazoline) (PiPOx).
Theoretical part will be focused on oxidation of graphene and controlled radical polymerizations. It will also focus on the possibilities of preparing hybrid particles, especially using controlled radical polymerizations. It also outlines the use of these systems.
In the experimental part, graphene oxides will be prepared by selected methods. The ability to reduce them using the ligands of the SI-ATRP catalytic system will be verified. The initiator will be bound onto GO particles and polymerization by PMMA and PiPOX will be carried out. GO particles and their hybrids will be characterized by different spectral and thermal methods. Finally, their electrical conductivity and the effect on the biocompatibility of hybrid particles will be evaluated.
Recommended resources
Yi, J., Choe, G., Park, J., Lee, J.Y. Graphene oxide-incorporated hydrogels for biomedical applications. Polymer Journal 2020, 52, 8, 823-837.
Ilcikova, M., Mrlik, M., Spitalsky, Z., Micusik, M., Csomorova, K., Sasinkova, V., Kleinova, A., Mosnacek, J. A tertiary amine in two competitive processes: reduction of graphene oxide vs. catalysis of atom transfer radical polymerization. RSC Advances, 2015, 5, 3370–3376.
Jankovsky, O., Marvan, P., Novacek, M., Luxa, J., Mazanek, V., Klimova, K., Sedmidubsky, D., Sofer, Z. Synthesis procedure and type of graphite oxide strongly influence resulting graphene properties. Applied Materials Today 2016, 4, 45-53.
Zygo, M., Mrlik, M., Ilcikova, M., Hrabalikova, M., Osicka, J., Cvek, M., Sedlacik, M., Hanulikova, B., Munster, L., Skoda, D., Urbanek, P., Pietrasik, J., Mosnacek, J. Effect of Structure of Polymers Grafted from Graphene Oxide on the Compatibility of Particles with a Silicone-Based Environment and the Stimuli-Responsive Capabilities of Their Composites. Nanomaterials 2020, 10, 3, 591.
Recommended resources
Yi, J., Choe, G., Park, J., Lee, J.Y. Graphene oxide-incorporated hydrogels for biomedical applications. Polymer Journal 2020, 52, 8, 823-837.
Ilcikova, M., Mrlik, M., Spitalsky, Z., Micusik, M., Csomorova, K., Sasinkova, V., Kleinova, A., Mosnacek, J. A tertiary amine in two competitive processes: reduction of graphene oxide vs. catalysis of atom transfer radical polymerization. RSC Advances, 2015, 5, 3370–3376.
Jankovsky, O., Marvan, P., Novacek, M., Luxa, J., Mazanek, V., Klimova, K., Sedmidubsky, D., Sofer, Z. Synthesis procedure and type of graphite oxide strongly influence resulting graphene properties. Applied Materials Today 2016, 4, 45-53.
Zygo, M., Mrlik, M., Ilcikova, M., Hrabalikova, M., Osicka, J., Cvek, M., Sedlacik, M., Hanulikova, B., Munster, L., Skoda, D., Urbanek, P., Pietrasik, J., Mosnacek, J. Effect of Structure of Polymers Grafted from Graphene Oxide on the Compatibility of Particles with a Silicone-Based Environment and the Stimuli-Responsive Capabilities of Their Composites. Nanomaterials 2020, 10, 3, 591.
