PhD-students currently working in this area:
Mercury in all its molecular forms is toxic. The element in wide-spread in nature and bio-accumulates in the food-chain. Additional environmental problems are created due to its indiscriminate use in gold mining and other industrial applications and its presence in crude oil and natural gas.
Determination of inorganic mercury and its two methylated forms is required in a wide range of sample types. The standard method for quantification is a complicated and time-consuming method utilizing gas-chromatographic separation coupled to ICP-MS after derivatisation of the compounds.
We developed a HPLC- cold vapour-atomic fluorescence spectrometry method, which does not required derivatisation and is able to detect the main natural mercury compounds in a variety of sample types. This method employs an on-line enrichment step, which allows detection limits at the pg/L (ppq) level.
- Brombach et al. Spectrochim. Acta 2015, ABC 2015
- Brombach et al. Food Chem. 2017
Application of this method showed not only that methylmercury is present in rice, but also that its concentration is highly variable in the ppb range and can make up up to 100% of total mercury.
Mercury is highly thiophillic. It does not only bind to thiol-groups of proteins but also peptides form stable complexes. This ability can be used analytically to determine the number of reduced thiol-groups present in a peptide / proteins.
Mercury can also form naturally sulphur containing nano-particles, which were among others detected in crude oil (Gajdosechova et al. Energy & Fuel 2016).
Mercury interacts also with other elements and influences their speciation in biological tissues.
A large thrust of our research is devoted to stranding mammals, especially pilot whales and the mercury/selenium and cadmium/selenium interactions in their metabolism especially the formation of natural nanoparticles in the liver and the brain (Gajdosechova et al. Sci. Tot. Environ. 2016, Sci. Rep. 2016, TrAC 2018)
The distribution of mercury in petrochemical fractions (crude oil, gas condensates, natural gas) is also depending on its speciation:
A further research area is the speciation of mercury present in crude oil. Data show that some of the mercury in crude oil is present in particulate form.
- Mercury distribution in a gas plant
- Hg –peptides in rice
- Methylmercury in water samples at the pg/L level by online preconcentration liquid chromatography cold vapor-atomic fluorescence spectrometry
- Methylmercury survey in rice with an emphasis on baby rice
- Hg Speciation in Petroleum Hydrocarbons with Emphasis on the Reactivity of Hg Particles
- Possible link between Hg and Cd accumulation in the brain of long-finned pilot whales (Globicephala melas)
- In vivo formation of natural HgSe nanoparticles in the liver and brain of pilot whales