| abstract |
An electrospray apparatus for dispensing a controlled volume of liquid in pulses at a constant frequency is provided. The apparatus comprises an emitter ( 70 ) having a spray area from which liquid can be sprayed, a means for applying an electric field ( 78 ) to liquid in, on or adjacent to the emitter ( 70 ). In use, liquid is drawn to the spray area by electrostatic forces and electrospray occurs in pulses at a constant frequency whilst the electric field ( 78 ) is applied. |