A series of fluorescent molecularly imprinted nanogels to detect irinotecan (CPT11) were prepared and characterized. A set of amino acids and napthalimide polymerisable derivatives allowed to obtain polymers as soluble fluorescent nanoparticles by high dilution imprinted synthesis. The direct detection of irinotecan in human plasma was obtained by fluorescence quenching of the naphtalimide-based imprinted materials. The plasma sample treated with acetonitrile allowed the detection of irinotecan in the 10nM – 30μM range. The LOD was 9.4 nM, with within-run variability 10% and day to day variability 13%.