The investigation of nucleobase oxidation is an important topic, as it can improve the understanding of DNA damaging processes. In this work, the electrooxidation of thymine on screen-printed carbon electrodes was investigated by hyphenation of electrochemistry and mass spectrometry (EC-MS). In the context of oxidative DNA damage, various methods for one-electron oxidation of nucleobases have been described in literature, as reviewed by Cadet et al [1] (e.g. ionizing radiation, type I photosensitizers, and radical anions). Detailed investigations based on electrochemical oxidation are scarce. However, electrooxidation offers various advantages such as high flexibility, well-controllable reaction conditions, and no need for additional reagents besides supporting electrolytes. EC-MS is a powerful tool for the investigation of redox reactions. By identification of electrogenerated products, reaction pathways can be unravelled. Using disposable electrode materials, time-consuming electrode maintenance procedures and memory effects can be avoided as electrodes can easily be replaced. In this contribution, different methods for characterization of electrochemical thymine oxidation will be presented. Real-time identification of oxidation products during an anodic potential sweep was facilitated by direct coupling of electrochemical flow cells to electrospray ionization mass spectrometry (ESI-MS). Thus, fast comparison of different electrolytes and evaluation of relevant potential regions was possible. By integrating an additional separation step between electrochemistry and mass spectrometry, ion suppression in the MS interface could be ruled out. Thus, further investigations were carried out by electrochemistry-capillary electrophoresis-mass spectrometry (EC-CEMS) and electrochemistry-high-performance liquid chromatography-mass spectrometry (EC-HPLC-MS). Different oxidation products could be detected and characterized based on the separation behaviour and fragmentation by collision-induced dissociation [2].

The investigation of nucleobase oxidation is an important topic, as it can improve the understanding of DNA damaging processes. In this work, the electrooxidation of thymine on screen-printed carbon electrodes was investigated by hyphenation of electrochemistry and mass spectrometry (EC-MS). In the context of oxidative DNA damage, various methods for one-electron oxidation of nucleobases have been described in literature, as reviewed by Cadet et al [1] (e.g. ionizing radiation, type I photosensitizers, and radical anions). Detailed investigations based on electrochemical oxidation are scarce. However, electrooxidation offers various advantages such as high flexibility, well-controllable reaction conditions, and no need for additional reagents besides supporting electrolytes. EC-MS is a powerful tool for the investigation of redox reactions. By identification of electrogenerated products, reaction pathways can be unravelled. Using disposable electrode materials, time-consuming electrode maintenance procedures and memory effects can be avoided as electrodes can easily be replaced. In this contribution, different methods for characterization of electrochemical thymine oxidation will be presented. Real-time identification of oxidation products during an anodic potential sweep was facilitated by direct coupling of electrochemical flow cells to electrospray ionization mass spectrometry (ESI-MS). Thus, fast comparison of different electrolytes and evaluation of relevant potential regions was possible. By integrating an additional separation step between electrochemistry and mass spectrometry, ion suppression in the MS interface could be ruled out. Thus, further investigations were carried out by electrochemistry-capillary electrophoresis-mass spectrometry (EC-CEMS) and electrochemistry-high-performance liquid chromatography-mass spectrometry (EC-HPLC-MS). Different oxidation products could be detected and characterized based on the separation behaviour and fragmentation by collision-induced dissociation [2].

The investigation of nucleobase oxidation is an important topic, as it can improve the understanding of DNA damaging processes. In this work, the electrooxidation of thymine on screen-printed carbon electrodes was investigated by hyphenation of electrochemistry and mass spectrometry (EC-MS). In the context of oxidative DNA damage, various methods for one-electron oxidation of nucleobases have been described in literature, as reviewed by Cadet et al [1] (e.g. ionizing radiation, type I photosensitizers, and radical anions). Detailed investigations based on electrochemical oxidation are scarce. However, electrooxidation offers various advantages such as high flexibility, well-controllable reaction conditions, and no need for additional reagents besides supporting electrolytes. EC-MS is a powerful tool for the investigation of redox reactions. By identification of electrogenerated products, reaction pathways can be unravelled. Using disposable electrode materials, time-consuming electrode maintenance procedures and memory effects can be avoided as electrodes can easily be replaced. In this contribution, different methods for characterization of electrochemical thymine oxidation will be presented. Real-time identification of oxidation products during an anodic potential sweep was facilitated by direct coupling of electrochemical flow cells to electrospray ionization mass spectrometry (ESI-MS). Thus, fast comparison of different electrolytes and evaluation of relevant potential regions was possible. By integrating an additional separation step between electrochemistry and mass spectrometry, ion suppression in the MS interface could be ruled out. Thus, further investigations were carried out by electrochemistry-capillary electrophoresis-mass spectrometry (EC-CEMS) and electrochemistry-high-performance liquid chromatography-mass spectrometry (EC-HPLC-MS). Different oxidation products could be detected and characterized based on the separation behaviour and fragmentation by collision-induced dissociation [2].

The development of reliable, cost-effective, sensitive, using small volume samples and fast devices for biomarker detection and monitoring is particularly important in clinical analysis. Screen-printed and microchip technologies allow to improve analytical performance by reducing the analysis time, sample volumes, and costs, making them even disposables. (Nanomaterial-based) electrochemical detection offers inherent miniaturization, high compatibility with micro and nanotechnologies, high sensitivity and cost efficiency. All in one, these features synergistically meet the clinical needs and, consequently, they are breaking new ground in developing point-of-care testing approaches. [1] In this Keynote, specifically, the analytical potential of electrochemical screen-printed sensors and microfluidic chips for reliable determination of high relevant (glyco)-proteins in clinical diagnosis, will be presented and discussed [2, 3]. Furthermore, the coupling of these electrochemical platforms with self-propelled catalytic micromotors will also be presented as new trend in (bio) analysis [4].

The development of reliable, cost-effective, sensitive, using small volume samples and fast devices for biomarker detection and monitoring is particularly important in clinical analysis. Screen-printed and microchip technologies allow to improve analytical performance by reducing the analysis time, sample volumes, and costs, making them even disposables. (Nanomaterial-based) electrochemical detection offers inherent miniaturization, high compatibility with micro and nanotechnologies, high sensitivity and cost efficiency. All in one, these features synergistically meet the clinical needs and, consequently, they are breaking new ground in developing point-of-care testing approaches. [1] In this Keynote, specifically, the analytical potential of electrochemical screen-printed sensors and microfluidic chips for reliable determination of high relevant (glyco)-proteins in clinical diagnosis, will be presented and discussed [2, 3]. Furthermore, the coupling of these electrochemical platforms with self-propelled catalytic micromotors will also be presented as new trend in (bio) analysis [4].

The development of reliable, cost-effective, sensitive, using small volume samples and fast devices for biomarker detection and monitoring is particularly important in clinical analysis. Screen-printed and microchip technologies allow to improve analytical performance by reducing the analysis time, sample volumes, and costs, making them even disposables. (Nanomaterial-based) electrochemical detection offers inherent miniaturization, high compatibility with micro and nanotechnologies, high sensitivity and cost efficiency. All in one, these features synergistically meet the clinical needs and, consequently, they are breaking new ground in developing point-of-care testing approaches. [1] In this Keynote, specifically, the analytical potential of electrochemical screen-printed sensors and microfluidic chips for reliable determination of high relevant (glyco)-proteins in clinical diagnosis, will be presented and discussed [2, 3]. Furthermore, the coupling of these electrochemical platforms with self-propelled catalytic micromotors will also be presented as new trend in (bio) analysis [4].

We recently demonstrated the creation of electrospun polyaniline (PANI) nanofibers bearing inherent multi-functionalities for bioanalytical applications via post-doping strategy. [2] We show that a simple doping of electrospun non-conductive PANI nanofibers with acid solutions not only was able to tackle challenges associated with the electrospinnability of highly conductive solutions, but also offered novel (bio)functionalities towards highly selective dopamine detection and polydopamine formation for electrocatalytic hydrazine sensing. Of special interest is also the impact of the post-doping process on the electroanalytical performance.

We recently demonstrated the creation of electrospun polyaniline (PANI) nanofibers bearing inherent multi-functionalities for bioanalytical applications via post-doping strategy. [2] We show that a simple doping of electrospun non-conductive PANI nanofibers with acid solutions not only was able to tackle challenges associated with the electrospinnability of highly conductive solutions, but also offered novel (bio)functionalities towards highly selective dopamine detection and polydopamine formation for electrocatalytic hydrazine sensing. Of special interest is also the impact of the post-doping process on the electroanalytical performance.

We recently demonstrated the creation of electrospun polyaniline (PANI) nanofibers bearing inherent multi-functionalities for bioanalytical applications via post-doping strategy. [2] We show that a simple doping of electrospun non-conductive PANI nanofibers with acid solutions not only was able to tackle challenges associated with the electrospinnability of highly conductive solutions, but also offered novel (bio)functionalities towards highly selective dopamine detection and polydopamine formation for electrocatalytic hydrazine sensing. Of special interest is also the impact of the post-doping process on the electroanalytical performance.

Among the multitude of concepts and different types of chemical sensors and biosensors discussed in literature, the strategy to integrate chemical or biological recognition elements together with semiconductor-type field-effect devices is one of the most attractive approaches. Typical examples are capacitive electrolyte-insulatorsemiconductor (EIS) field-effect sensors, light-addressable potentiometric sensors (LAPS) or ion-sensitive field-effect transistors (ISFETs). These sensors provide a lot of potential advantages over conventional approaches such as small size and weight, fast response time, possibility of on-chip integration of sensor arrays, high robustness, and possibility of low-cost fabrication. Possible fields of application reache from medicine, biotechnology, process control and environmental monitoring through food and drug industries up to defense and security requirements. This presentation gives an overview on recent examples of capacitive, silicon-based field-effect (bio-)chemical sensors developed at the Institute of Nano- and Biotechnologies. The sensors have been dealing with different receptor molecules such as enzymes, polyelectrolytes or DNA molecules, respectively, as well as device concepts and various immobilization strategies.

Among the multitude of concepts and different types of chemical sensors and biosensors discussed in literature, the strategy to integrate chemical or biological recognition elements together with semiconductor-type field-effect devices is one of the most attractive approaches. Typical examples are capacitive electrolyte-insulatorsemiconductor (EIS) field-effect sensors, light-addressable potentiometric sensors (LAPS) or ion-sensitive field-effect transistors (ISFETs). These sensors provide a lot of potential advantages over conventional approaches such as small size and weight, fast response time, possibility of on-chip integration of sensor arrays, high robustness, and possibility of low-cost fabrication. Possible fields of application reache from medicine, biotechnology, process control and environmental monitoring through food and drug industries up to defense and security requirements. This presentation gives an overview on recent examples of capacitive, silicon-based field-effect (bio-)chemical sensors developed at the Institute of Nano- and Biotechnologies. The sensors have been dealing with different receptor molecules such as enzymes, polyelectrolytes or DNA molecules, respectively, as well as device concepts and various immobilization strategies.

Among the multitude of concepts and different types of chemical sensors and biosensors discussed in literature, the strategy to integrate chemical or biological recognition elements together with semiconductor-type field-effect devices is one of the most attractive approaches. Typical examples are capacitive electrolyte-insulatorsemiconductor (EIS) field-effect sensors, light-addressable potentiometric sensors (LAPS) or ion-sensitive field-effect transistors (ISFETs). These sensors provide a lot of potential advantages over conventional approaches such as small size and weight, fast response time, possibility of on-chip integration of sensor arrays, high robustness, and possibility of low-cost fabrication. Possible fields of application reache from medicine, biotechnology, process control and environmental monitoring through food and drug industries up to defense and security requirements. This presentation gives an overview on recent examples of capacitive, silicon-based field-effect (bio-)chemical sensors developed at the Institute of Nano- and Biotechnologies. The sensors have been dealing with different receptor molecules such as enzymes, polyelectrolytes or DNA molecules, respectively, as well as device concepts and various immobilization strategies.