Foto del docente

Giovanna Farruggia

Assistant professor

Department of Pharmacy and Biotechnology

Academic discipline: BIO/10 Biochemistry


Keywords: fluorescece spectroscopy flow cytometry magnesium fluorescent dye cell proliferation

1)      Study of new biosensors for intracellular cations, in particular for magnesium and zinc: characterization of their spectroscopic features and of their biological application, with particular interest to the magnesium cellular and tissutal homeostasis, in physiological and pathological conditions. This study is based on the integration of different techniques, because it considers the feasibility of spectroscopic, microscopic and cytofluorimetric approaches for the assessment of cell magnesium and its fluxes, comparing the results of magnesium analysis in blood cells of  healthy donor and of patients of  selected diseases with 31P –NMRS assays “in vivoâ€. Characterization of new fluorescent probes for Cadmium, to employ in toxicological assays.

2)      Study of application of X-ray microscopy to intracellular ion mapping.

3) Study of cellular magnesium homeostasis and of the role played by this cation in several aspect of cellular biology, mainly in cell cycle progression od normal and transformed cells, apoptosis and Multi-Drug Resistance.

4) Study of antiproliferative e MDR revertant effects of potential anticancer drugs. 



The research on new fluorescent  biosensors for intracellular cations, mainly for magnesium, has been focussed on a class of fluorescent dyes based on diaza-18-crown-6 appended with two hydroxyquinoline groups, bearing different atoms in position 5. In particular the two molecules bearing H (DCHQ1) o Cl (DCHQ2) substituents showed high affinity and specificity for magnesium and no interference with calcium, as displayed by commercial probes such as Mag-Fura and Mag-fluo. The characterization of the DCHQ1 is quite advanced: DCHQ1 is well tolerated by cells, allows to evaluate intracellular total magnesium and monitor fast intracellular magnesium transients after mitochondrial stimuli. Therefore, this molecule has the potential to be successfully employed in the study of magnesium homeostasis, representing in addition, an alternative to atomic absorption spectroscopy (AAS) in total intracellular magnesium evaluation, especially when biological specimens of reduced dimensions are available.

The photochemical characterization of DCHQ2 is quite completed and now we are studing a new derivatives; among them a DCHQ-AM, which could be entrapped within the cells.

The biochemical and photochemical characterization of DCHQ probes and their derivatives are carried out to assay their applicability to total intracellular magnesium and its fluxes by means of spectrofluorimetry, fluorescence microscopy and flow cytometry. Thwese studies are carried on in collaboration with Prof.F.I. Wolf of the Università Cattolica di Roma and with Prof. J. Meier  of the Università Statale di Milano

The next research projects will focus on: i)  application of the dye DCHQ1 to the evaluation of the total intracellular magnesium to blood cells, comparing the measures obtained with this dye in erythrocytes, platelets and lymphocytes of healthy donors with those obtained by AAS. Similar determinations will be performed with the other members of the DCHQ family that have showed suitable characteristics similar to DCHQ1;  ii) application of these assays on patients affected by pathologies where a deficit in plasma magnesium levels has been reported. However, it is not yet clarified how this alteration influences the intracellular levels of total and free intracellular magnesium in different tissues. The tissue distribution of magnesium will be performed by different spectroscopic techniques, as 31P-MRS and standard techniques (AAS, colorimetry and Mag-Fura fluorimetry).  In particular, fluorescence spectroscopy and flow cytometry will be used to evaluate magnesium by commercial probes (Mag-fura and/or Mag-fluo) and by DCHQ probes in blood cells (lymphocytes, erythrocytes and platelets), and the results will be integrated by free cytosolic Mg2+  measured in brain and in skeletal muscle by 31P-MRS by Prof. S. Iotti of Dipartimento di Medicina Interna, dell'Invecchiamento e Malattie Nefrologiche,  University ofi Bologna; iii) study of  other derivatives of Hydroquinoline  specific for other cations of biological interest, as Zn; iv) study of the applications of X-ray microscopy toimage the intracellular topography and the valence status of a variety of atomic elements with high spatial resolution, in collaboration with Prof. S. Lagormasino of CNR, Rome.