Abstract: The present invention relates to a microfluidic device (2) comprising a support part (21) and a cover part (22) defining together a microchannel (5), said microchannel (5) having a surface, said surface comprising:—a first area (9) which is grafted with a first ligand, and—at least a second area (10) which is distinct from the first area (9) and which is grafted with a second ligand which is different from the first ligand, wherein each ligand is capable of binding to a target, the targets being different from each other. The present invention further relates to a microfluidic detection system comprising the said microfiuidic device, a reservoir adapted for containing a sample to be analysed and a detection device for detecting and quantifying the targets. The present invention relates also to a method for manufacturing such a microfluidic device, as well as a method for analysing a sample containing targets using the said microfluidic device or microfluidic detection system.