A droplet dispensing apparatus comprising: a droplet ejecting array having a plurality of nozzles from which solution can be ejected into a microplate on a baseplate; a sensor configured to detect a solution amount in the microplate; and a controller configured to: detect that a nozzle in the plurality of nozzles is malfunctioning during a solution ejection process based on an initial solution amount in the microplate and a final solution amount in the microplate as detected by the sensor, and control a supplemental droplet dispensing operation in which an additional solution amount is ejected into the microplate based on the initial solution amount and the final solution amount in the microplate; characterized in that the sensor comprises a scale configured to weigh of the microplate on the baseplate to determine the solution in the microplate, and the controller is further configured to: calculate an expected weight decrease due to drying during the solution ejection process based on an initial weight of the microplate on the baseplate and a reference weight of the microplate on the baseplate as measured after a predetermined time after the initial weight is measured, and signal at least one nozzle in the plurality of nozzles is malfunctioning, when a final weight of the microplate is less than the initial weight plus any expected weight increase due to droplets ejected during the solution ejection process minus the expected weight reduction due to drying. a droplet ejecting array having a plurality of nozzles from which solution can be ejected into a microplate on a baseplate; a sensor configured to detect a solution amount in the microplate; and a controller configured to: detect that a nozzle in the plurality of nozzles is malfunctioning during a solution ejection process based on an initial solution amount in the microplate and a final solution amount in the microplate as detected by the sensor, and control a supplemental droplet dispensing operation in which an additional solution amount is ejected into the microplate based on the initial solution amount and the final solution amount in the microplate; characterized in that detect that a nozzle in the plurality of nozzles is malfunctioning during a solution ejection process based on an initial solution amount in the microplate and a final solution amount in the microplate as detected by the sensor, and control a supplemental droplet dispensing operation in which an additional solution amount is ejected into the microplate based on the initial solution amount and the final solution amount in the microplate; characterized in that the sensor comprises a scale configured to weigh of the microplate on the baseplate to determine the solution in the microplate, and the controller is further configured to: calculate an expected weight decrease due to drying during the solution ejection process based on an initial weight of the microplate on the baseplate and a reference weight of the microplate on the baseplate as measured after a predetermined time after the initial weight is measured, and signal at least one nozzle in the plurality of nozzles is malfunctioning, when a final weight of the microplate is less than the initial weight plus any expected weight increase due to droplets ejected during the solution ejection process minus the expected weight reduction due to drying. calculate an expected weight decrease due to drying during the solution ejection process based on an initial weight of the microplate on the baseplate and a reference weight of the microplate on the baseplate as measured after a predetermined time after the initial weight is measured, and signal at least one nozzle in the plurality of nozzles is malfunctioning, when a final weight of the microplate is less than the initial weight plus any expected weight increase due to droplets ejected during the solution ejection process minus the expected weight reduction due to drying.