The setup of instrumental methods for the determination and speciation of trace elements in both natural and manmade materials, combining different analytical techniques is the main research topic. The preanalytical and analytical steps, i.e. choice of the analytical method, sampling, sampling storage, pretreatment, detection, statistical evaluation and method validation are critically assessed. Performance enhancement has been achieved by the development of new hardware, the setup of novel methods and the optimisation of existing ones. Prof. Monticelli gained expertise in the field of electroanalytical techniques (anodic and cathodic stripping), spectroscopic methods (Electrothermal Atomic Absorption Spectroscopy and Total Reflection X-Ray Fluorescence) and mass spectrometric (Inductively Coupled Plasma – Mass Spectrometry). The latter was employed with both liquid introduction and solid sampling by laser ablation (LA-ICP-MS).
The setup of procedures for the speciation analysis of trace elements is the second active field of research. These studies enable the form of trace elements to be determined defining their inorganic and organic reactivity in natural waters. The competitive ligand equilibration with cathodic stripping voltammetric detection of the labile fraction (CLE-CSV) is used for this aim. Methodological investigations and applied research were undertaken. The figures of merit of the method were firstly assessed: all of the steps were carefully assessed, and critical points highlighted. As a result, accuracy and precision of the procedure were, for the first time, measured. An effort was also made to understand the molecular bases for the cathodic stripping voltammetric procedure to further increase performances. The speciation method was subsequently applied to the detection of copper speciation in remote areas, like Alpine lakes, ice streams and open ocean waters. The speciation of copper ion was initially investigated, whereas the focus was moved to iron during the last five years in view of its importance in oceanic biogeochemical cycles.