An apparatus and methods for the precise, repeatable dispensing of small, sample fluid volumes, especially as related to the printing of microarrays for biological and/or chemical testing. A pressure tuning module meters fluid volumes for aspiration and dispensation and builds pressure for fluid dispensation, in conjunction with a microvalve that precisely controls the volume of the fluid dispensed under the built pressure. A pressure source can be switched in line to efficiently purge the apparatus of residual sample fluid. A working fluid can be optionally aspirated into the system, prior to aspirating the sample fluid, in order to maximize sample fluid recovery.