Thesis defense of Coline BELTRAMI

Thesis defense of Coline BELTRAMI, PhD student in the Biophotonics group of the Laboratoire Charles Fabry, on Friday 20 December 2024 at 02:00pm in the Auditorium of the Institut d'Optique Graduate School in Palaiseau, on the topic: "Plasmonic biosensor development for low-concentration detection of miRNAs in the context of organ donation."

Abstract: "Monitoring the physiological conditions of brain-deceased organ donors is crucial to prevent tissue degradation. This can be achieved by following the inflammatory response (i.e. cytokine storm) through specific biomarkers like miRNAs. This work proposes using Surface Plasmon Resonance Imaging (SPRI) combined with a gold nanoparticle amplification protocol to quantitatively detect specific miRNAs sequences at very low concentrations.

To achieve this objective, a chemical functionalization of the biochip’s gold surface was developed to improve receptors accessibility. These receptors are oligonucleotides modified with LNA bases that exhibit high affinity for the target miRNA sequences. In parallel, a strategy for amplifying the SPRI signal using gold nanoparticles was designed. A one-step synthesis protocol at room temperature was optimised. These nanoparticles are functionalised to be specific to the target miRNA and highly soluble in saline solution.

These combined approaches resulted in a signal amplification of over two orders of magnitude and a miRNA detection limit in the picomolar range."