LA-ICP-MS Systems for Bioimaging: Towards Representative Sampling, Fast Washout, High Spatial Resolution and Sensitive Detection of Organic Aerosols

This thesis is addressed to the improvement of LA-(Q)-ICP-MS systems for the ablation, washout and transport of organic aerosols and their subsequent detection. In doing so, various optimization possibilities adjusted specifically to bioimaging applications shall be presented. To begin with, the performance of state-of-the-art LA-Q-ICP-MS systems available on the market shall be discussed with the focus placed on the influence of the respective ablation cell design and the transport system on the washout of organic aerosols. Thus, general insights into the basic performance of LA systems for bioimaging shall be provided. In addition, improved optimization strategies for ICP-MS systems shall be addressed by introducing self-written tuning sequences and investigating the performance of a CRI for interference removal.Subsequently, new ablation cell designs and a modified transport system for an optimized material washout during bioimaging applications shall be presented, along with a modified interfacing of commercially available LA-ICP-MS systems for improved sample introduction. Second, a solution to further decrease the available spot size for a spatial resolution towards cellular and sub cellular levels within a commercial LA system shall be suggested.For deeper insights into the fundamentals during the ablation of organic materials, aerosol characteristics and possible fractionation effects depending on laser parameters, transport characteristics and ionization conditions within the ICP shall be investigated and compared to those of inorganic solids.Finally, high resolution bioimaging experiments for a detailed investigation of the natural distribution of essential elements within substructures of diverse tissue types shall be presented. In doing so, efficient tuning strategies for a CRI and cold plasma conditions shall be suggested to enable the highest sensitivities for challenging analytes in bioimaging applications.