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摘要: Pro-inflammatory cytokines are molecules involved in several pathologies (cancer, depressive disorders, CoViD-19,…) and found in various biological fluids (blood, sweat, saliva…). Developing a biosensor that could identify and quantify cytokines in these fluids represents an innovative approach for the monitoring of pro-inflammatory pathologies. In this context, the objective of this thesis has been to develop a microfluidic device integrating functionalized magnetic beads for the capture and manipulation of the Tumor Necrosis Factor Alpha (TNF-α), a model cytokine. Inside the device, the capture of TNF-α is performed with magnetic beads functionalized with antibodies inside a microfluidic circuit. The beads are captured and manipulated with integrated microcoils. The device also includes a microfluidic detection chamber biofunctionalized with anti-TNF-α antibodies allowing the immobilization of the magnetic beads-TNF-α immunocomplexes. These complexes are then quantified by fluorescence microscopy. In the first part of the thesis, a chemical functionalization process of PDMS, as constituting material of the microfluidic chip, has been developed and optimized for the fabrication of the detection chamber. This functionalization process relies on an amino-silanization reaction and has been characterized with different physico-chemical techniques: water contact angle, EDX, AFM, FTIR and fluorescence microscopy. The prepared surfaces have been validated with an immunoassay on TNF-α with a limit of detection of 0.55 µg/mL (31.6 nM) in fluorescence microscopy [1]. Next, the microfluidic integration of this process relied on the assembly of …