An ink jet printer valve and a nozzle were used to deliver matrix and sample from an electrophoresis capillary onto a MALDI plate. The system was evaluated by the separation of a set of standard peptides. That separation generated up to 40 000 theoretical plates in less than 3 min. Detection limits were 500 amol for an ABI TOF-TOF instrument and 2 fmol for all ABI Q-TOF instrument Over 70% coverage was obtained for the tryptic digest of alpha-lactalbumin in less than 2 5 min.