Graphene nanoribbons (GNRs) are used as a current carrying substrate in investigation of current-induced forces in a low-temperature STM (chapter 2). We demonstrate induced migration of Co adatoms... Show moreGraphene nanoribbons (GNRs) are used as a current carrying substrate in investigation of current-induced forces in a low-temperature STM (chapter 2). We demonstrate induced migration of Co adatoms on GNRs and on Au(111) using voltage pulses from the STM tip and we argue that motion is due to thermal excitations rather than the wind force. In chapter 3 we show that voltage signal is induced in a graphene strip when a droplet of ionic liquid is moved across its surface. Here we show that even deionized water can induce voltage over charged graphene surface due to the polarizability of water molecules. In chapter 4 we present a method for fabrication of graphene nanoelectrodes which we further test electrically in a modified STM. For the first time we demonstrate that the gap between two graphene nanoelectrodes can be tuned with subnanometric precision Show less
In thesis the power of electrophoretic on-line concentration procedures for peptidomics and metabolomics is demonstrated. Tow examples are given: isotachophoresis with spacer molecules and... Show moreIn thesis the power of electrophoretic on-line concentration procedures for peptidomics and metabolomics is demonstrated. Tow examples are given: isotachophoresis with spacer molecules and electroextraction. Electromigration is capable of enhancing selective analyte migration. Selective analyte migration can be used to increase the amount of analyte that is injected into an analytical system, while it leaves the sample volume with the contaminants behind. In consequence, the injection of contaminants and bulk components that may disturb sample pretreatment, separation and detection can be avoided and LOD values can be lowered without the problems associated with direct injection of larger sample volumes. The work that is presented in this thesis is focused on fast electrophoresis-based LOD improvement of the analysis of peptides and/or metabolites in plasma and urine. Show less