P1-0034 — Annual report 2010
1.
Basic modeling approach to optimize elemental imaging by laser ablation ICPMS.

We developed a mathematical model, and ensuing software, for simulation of the laser ablation (LA) - ICP-MS elemental imaging process based on virtual rastering of a digital image of the sample. This allows optimization of all major instrumental settings for generation of high-quality element maps prior to the actual experiment. In this way damage to often unique and precious samples is avoided, whereas the analysis time and costs are significantly minimized.

COBISS.SI-ID: 4547610
2.
Assessment of physical leaching processes of some elements in soil upon ingestion by continuous leaching and modeling.

The article outlines the mathematical modelling of the leaching profiles of some elements (B, Cd, Co, Mn, Ni, and Sr) from soils from Cornwall, UK, when exposed to an artificial gastric solution. The modelling allowed the quantification of the influence of liquid film diffusion and apparent solid phase diffusion on the liability of the elements upon ingestion.

COBISS.SI-ID: 4448538
3.
Light induced multiphase chemistry of gas-phase ozone on aqueous pyruvic and oxalic acids.

For the first time it has been shown that pyruvic acid can affect the atmospheric multiphase reactions of ozone with oxalic acid due to its properties as a photosensitizer. The photochemical multiphase reactions of pyruvic / oxalic acid (PA/OA) and ozone under simulated sunlight were studied using liquid chromatography (HPLC-UV) and electrospray ionization mass spectrometry (ESI-MS). The HPLC-UV analysis of the reaction mixture exposed to ozone and simulated sunlight revealed the presence of high weight molecular mass products and formation of highly non-polar products.

COBISS.SI-ID: 33739269
4.
Amperometric microsensor for direct probing of ascorbic acid in human gastric juice.

We developed a microsensor for amperometric probing of ascorbic acid (AA) in gastric juice. This was achieved by modifying the surface of a substrate carbon fiber microelectrode with an electrochemically deposited nickel oxide and ruthenium hexacyanoferrate layer, using a two-step galvanostatic-potentiodynamic protocol, with further application of a cellulose-acetate protective coating. The signal to AA concentration relationship in acidic media (0.01 M HCl or gastric juice) was linear over a wide range corresponding to physiological AA concentrations commonly encountered in gastric juice.

COBISS.SI-ID: 4530970
5.
Ultrasound-assisted solid liquid extraction (USLE) of olive fruit (Olea euro-paea) phenolic compounds.

New method for extraction of phenols from olives was developed. The phenols were extracted by using the ultrasound, and determined by HPLC-DAD-FLD-MS/MS. The time of sonication, temperature, ratio of solvent volumes and number of extractions were optimized. The developed methods gives 80% higher extraction yields compared to the method relying on shaking, as it was demonstrated for oleuropein. The described extraction procedure offers better selectivity, sensitivity and accuracy of analytical method.

COBISS.SI-ID: 1464827