A cartridge for a handheld electrohydrodynamic (EHD) spraying device and a spraying device incorporating the cartridge. The cartridge is disposable, and can contain therapeutic products. The device includes a wetted lead screw with a compliant seal, where the placement of the seal relative to the screw inhibits leakage during both cartridge use and storage. A frame disposed within the cartridge acts as a load-transferring mechanism for the weight of the cartridge to a handle of the spraying device.