An embodiment relates to a method of detecting a drug resistance in a patient comprising adding nanoparticles to sample platelets to form activated platelets containing the nanoparticles and comparing a difference in activation of the activated platelets and the sample platelets. Another embodiment relates to a method of monitoring a thrombotic risk factor in a subject in a general population comprising adding nanoparticles to sample platelets to form activated platelets containing the nanoparticles and comparing a difference in activation of the activated platelets and the sample platelets. Yet another embodiment relates to a kit comprising nanoparticles, a fluorescence dye tagged antibody and optionally a buffer, wherein the kit is configured to detect a drug resistance in a patient or a likelihood of the thrombotic risk factor in a subject in general population.