"Membrane and Stress" Technical Core Facility

Scientific advisor : Odile Sergent (PU), Dominique Lagadic-Gossmann (DR CNRS). Technical advisor : Isabelle Gallais (IE Inserm).

Electron Paramagnetic Resonance (EPR) for the measurement of  membrane fluidity and oxidative/nitrosative stress
  1. Electron Paramagnetic Resonance (EPR)
  2. Microspectrofluorimetry
  3. ​HPLC

Electron Paramagnetic Resonance (EPR)

Electron Paramagnetic Resonance (EPR), also often called Electron Spin Resonance (ESR) is a method to detect and quantify paramagnetic species such as free radicals and transition metal ions essential for analyses of chemical agent-induced oxidative stress in cells and tissues. EPR allows not only to evaluate oxidative membrane damages by measuring lipid radicals but also to unravel the initial toxic mechanisms by detecting oxygen free radicals, free iron levels and nitric oxide (NO). Chemical agents can also exert their membrane toxicity by altering membrane fluidity. As lineshapes in spectra are very sensitive to the environment around the free radical, EPR is also a method of choice to evaluate membrane fluidity.

Microspectrofluorimetry

Microspectrofluorimetry is based on fluorescent probes for example specific for calcium (Fura-2, Indo-1) or for protons (Carboxy-SNARF-1). The set-up enables us to measure the intracellular calcium concentration or intracellular pH from purified or cultured living cells in real time. Since this apparatus is equipped with a superfusion system it is possible to change solutions very rapidly which makes it possible to measure extremely rapid changes in calcium homeostasis or intracellular pH induced by different molecules or conditions.

​HPLC

HPLC for measurement of oxidative stress (malondialdehyde) and cytochrome P450s’ activity.