Method of depositing single particles onto a target, comprising the steps of - loading a particle suspension to a droplet dispenser having a suspension reservoir and a nozzle section, wherein the droplet dispenser is capable of dispensing droplets having a predetermined first droplet volume, - detecting a presence of particles in the nozzle section, - controlling the droplet dispenser based on a test procedure, which comprises (i) testing a single particle condition of the droplet dispenser, wherein it is determined whether a predetermined first ejection region of the nozzle section includes one single particle and a sedimentation region adjacent to the ejection region is free of particles, wherein the sedimentation region is a zone through which particles are displaced to the ejection region by sedimentation during an operation delay interval between the step of detecting the presence of particles and a step of operating the droplet dispenser, and (ii) testing a zero particle condition of the droplet dispenser, wherein it is determined whether an axial length of the droplet dispenser beginning at a tip of the nozzle section and comprising at least the twofold regular ejection region volume is free of particles to be dispensed, and - operating the droplet dispenser, wherein one droplet is dispensed onto the target, if the single particle condition is fulfilled, or at least two droplets are discarded into a collection reservoir, if the single particle condition is not fulfilled and the zero particle condition is fulfilled, or one droplet is discarded into the collection reservoir, if the single particle condition is not fulfilled and the zero particle condition is not fulfilled. - loading a particle suspension to a droplet dispenser having a suspension reservoir and a nozzle section, wherein the droplet dispenser is capable of dispensing droplets having a predetermined first droplet volume, - detecting a presence of particles in the nozzle section, - controlling the droplet dispenser based on a test procedure, which comprises (i) testing a single particle condition of the droplet dispenser, wherein it is determined whether a predetermined first ejection region of the nozzle section includes one single particle and a sedimentation region adjacent to the ejection region is free of particles, wherein the sedimentation region is a zone through which particles are displaced to the ejection region by sedimentation during an operation delay interval between the step of detecting the presence of particles and a step of operating the droplet dispenser, and (ii) testing a zero particle condition of the droplet dispenser, wherein it is determined whether an axial length of the droplet dispenser beginning at a tip of the nozzle section and comprising at least the twofold regular ejection region volume is free of particles to be dispensed, and (i) testing a single particle condition of the droplet dispenser, wherein it is determined whether a predetermined first ejection region of the nozzle section includes one single particle and a sedimentation region adjacent to the ejection region is free of particles, wherein the sedimentation region is a zone through which particles are displaced to the ejection region by sedimentation during an operation delay interval between the step of detecting the presence of particles and a step of operating the droplet dispenser, and (ii) testing a zero particle condition of the droplet dispenser, wherein it is determined whether an axial length of the droplet dispenser beginning at a tip of the nozzle section and comprising at least the twofold regular ejection region volume is free of particles to be dispensed, and - operating the droplet dispenser, wherein one droplet is dispensed onto the target, if the single particle condition is fulfilled, or at least two droplets are discarded into a collection reservoir, if the single particle condition is not fulfilled and the zero particle condition is fulfilled, or one droplet is discarded into the collection reservoir, if the single particle condition is not fulfilled and the zero particle condition is not fulfilled.