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Development of a sensing platform for the study of physiological functions of living cells
Marková, Aneta ; Víteček, Jan (referee) ; Vala, Martin (advisor)
The aim was to develop a sensing platform on the base of organic electrochemical transistor (OECT). The focus was on the preparation of proper electrode system and on optimalization of properties of thin layer of organic semiconductor. As a base, commercial glass substrates with integrated indium-tin oxide electrodes were chosen. Thin layers were prepared from organic semiconductor poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) by spin-coating. Four formulations of material were studied. Layers with different thickness were prepared and the dependence of transconductance on the thickness of the layer and ratio of width and length was observed. The degradation of electrode system was solved by galvanic plating with gold. Attention was also paid to modifications to PEDOT: PSS. It has been found that the optimal layer thickness for use in sensors is approximately 150 nm. By reducing the series resistance by using a silver paste, the transconductance of 23 mS was obtained for the Ink 2, for the Ink 3 the transconductance was 44 mS. Sensoric platforms with these transconductances can be used for detection of physiological functions of electrogenic cells, e.g. cardiomyocytes.
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Optimization of printing of organic electronic devices printing for bioelectronics
Bráblíková, Aneta ; Hrabal, Michal (referee) ; Salyk, Ota (advisor)
This bachelor thesis is focused on optimization of printing of organic electronic devices printing for bioelectronics. The main goal of this bachelor thesis is a series of experiments devised to optimize semiconductive structures of PEDOT (semiconductive polymer) and description of the process used in the preparation of organic electrochemical transistors for biosensor by screen printing technology. The research focused on application of bioelectronics, printing technologies, conductive inks suitable for the preparation of OECTs (organic electrochemical tranzistors) and rheological properties of materials. Main conditions tested in the experimental part were temperature, stirring and additon of DMSO (dimethylsulfoxide) into a printing pasted. The evaluated parameters of materials were basic viscoelastic characteristics. At the ent of the thesis have been successfully designed the series of transistors to monitor cell cultures.
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Organic tranistors for sensorics
Marková, Aneta ; Omasta, Lukáš (referee) ; Vala, Martin (advisor)
The aim was to find the best available commercial formulation of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and methods and subsequent treatment of thin films for organic electrochemical transistors (OECT). These films will be used in bioelectronic sensors to measure the physiological function of cardiomyocytes. Studied material was PEDOT:PSS in six different formulations. Thin layers prepared by spin coating were modified in three ways, namely (i) immersion in ethylene glycol, (ii) drying and (iii) a combination of drying and ethylene glycol. The layers were then tested for the influence of ethylene glycol, thermal stability, the impact of storage, influence of aqueous medium, and additional thermal annealing. According to the results obtained, the most suitable treatment of most materials was immersion in ethylene glycol followed by thermal annealing of the layer. It was found that the most appropriate material formulation was Sigma Aldrich 739 316 treated by the combination of drying, immersion in ethylene glycol and thermal annealing.
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Electro-optical sensor for the detection of extracellular ions
Bellan, Boris ; Salyk, Ota (referee) ; Vala, Martin (advisor)
The aim of this work was to prepare a platform based on electrochemical transistor that would allow both electrical and optical detection of ion exchange between the electrolyte and the layer of organic semiconductor. Semiconductor that have been used in this work was poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate). The main goal was to verify whether the proposed platform meets the requirements of both characterization methods, and whether the sensitivity in the given arrangement is sufficient for the required range of analyte concentrations. The work also dealt with the study of the stability of the prepared platform in selected solvents and culture media, at the same time the method of optimizing the preparation of the photoresist foil and the completion of the OECT measuring cell was studied. A suitable solvent for polymethyl methacrylate was sought so that it did not affect the surrounding parts of the platform. Based on the obtained results, it was found that the selected photoresist for the preparation of the spacer frame is not suitable. However, it was found that the proposed platform satisfies both characterization methods. Therefore, it will be necessary to replace the current photoresist with a new, more chemically stable one.
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Electro-optical sensor for the detection of extracellular ions
Bellan, Boris ; Salyk, Ota (referee) ; Vala, Martin (advisor)
The aim of this work was to prepare a platform based on electrochemical transistor that would allow both electrical and optical detection of ion exchange between the electrolyte and the layer of organic semiconductor. Semiconductor that have been used in this work was poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate). The main goal was to verify whether the proposed platform meets the requirements of both characterization methods, and whether the sensitivity in the given arrangement is sufficient for the required range of analyte concentrations. The work also dealt with the study of the stability of the prepared platform in selected solvents and culture media, at the same time the method of optimizing the preparation of the photoresist foil and the completion of the OECT measuring cell was studied. A suitable solvent for polymethyl methacrylate was sought so that it did not affect the surrounding parts of the platform. Based on the obtained results, it was found that the selected photoresist for the preparation of the spacer frame is not suitable. However, it was found that the proposed platform satisfies both characterization methods. Therefore, it will be necessary to replace the current photoresist with a new, more chemically stable one.
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|
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Development of a sensing platform for the study of physiological functions of living cells
Marková, Aneta ; Víteček, Jan (referee) ; Vala, Martin (advisor)
The aim was to develop a sensing platform on the base of organic electrochemical transistor (OECT). The focus was on the preparation of proper electrode system and on optimalization of properties of thin layer of organic semiconductor. As a base, commercial glass substrates with integrated indium-tin oxide electrodes were chosen. Thin layers were prepared from organic semiconductor poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) by spin-coating. Four formulations of material were studied. Layers with different thickness were prepared and the dependence of transconductance on the thickness of the layer and ratio of width and length was observed. The degradation of electrode system was solved by galvanic plating with gold. Attention was also paid to modifications to PEDOT: PSS. It has been found that the optimal layer thickness for use in sensors is approximately 150 nm. By reducing the series resistance by using a silver paste, the transconductance of 23 mS was obtained for the Ink 2, for the Ink 3 the transconductance was 44 mS. Sensoric platforms with these transconductances can be used for detection of physiological functions of electrogenic cells, e.g. cardiomyocytes.
|
|
|
Optimization of printing of organic electronic devices printing for bioelectronics
Bráblíková, Aneta ; Hrabal, Michal (referee) ; Salyk, Ota (advisor)
This bachelor thesis is focused on optimization of printing of organic electronic devices printing for bioelectronics. The main goal of this bachelor thesis is a series of experiments devised to optimize semiconductive structures of PEDOT (semiconductive polymer) and description of the process used in the preparation of organic electrochemical transistors for biosensor by screen printing technology. The research focused on application of bioelectronics, printing technologies, conductive inks suitable for the preparation of OECTs (organic electrochemical tranzistors) and rheological properties of materials. Main conditions tested in the experimental part were temperature, stirring and additon of DMSO (dimethylsulfoxide) into a printing pasted. The evaluated parameters of materials were basic viscoelastic characteristics. At the ent of the thesis have been successfully designed the series of transistors to monitor cell cultures.
|
|
|
Organic tranistors for sensorics
Marková, Aneta ; Omasta, Lukáš (referee) ; Vala, Martin (advisor)
The aim was to find the best available commercial formulation of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and methods and subsequent treatment of thin films for organic electrochemical transistors (OECT). These films will be used in bioelectronic sensors to measure the physiological function of cardiomyocytes. Studied material was PEDOT:PSS in six different formulations. Thin layers prepared by spin coating were modified in three ways, namely (i) immersion in ethylene glycol, (ii) drying and (iii) a combination of drying and ethylene glycol. The layers were then tested for the influence of ethylene glycol, thermal stability, the impact of storage, influence of aqueous medium, and additional thermal annealing. According to the results obtained, the most suitable treatment of most materials was immersion in ethylene glycol followed by thermal annealing of the layer. It was found that the most appropriate material formulation was Sigma Aldrich 739 316 treated by the combination of drying, immersion in ethylene glycol and thermal annealing.
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