The present invention relates to a process for making an array comprising array points in a predetermined pattern on a substrate, each of the array points comprising a predetermined number of a particulate object capable of functioning in an aqueous condition. The process comprises the steps of: (A) providing a hydrophobic liquid onto the substrate, (B) depositing a predetermined number of microdroplets of an aqueous suspension containing the particulate object in each of the array points by inkjet technology. The predetermined number of the microdroplets of the suspension is determined as a function of the concentration of the suspension and the average volume of the microdroplets of the suspension.