Methods for dispensing tools that can be employed to generate
multi-element arrays of sample material on a substrate surface. The
resulting substrates are also provided. The substrates surfaces can be
flat or geometrically altered to include wells of receiving material. The
tool can dispense a spot of fluid to a substrate surface by spraying the
fluid from the pin, contacting the substrate surface or forming a drop
that touches against the substrate surface. The tool can form an array of
sample material by dispensing sample material in a series of steps, while
moving the pin to different locations above the substrate surface to form
the sample array. The prepared sample arrays are passed to a plate
assembly that disposes the sample arrays for analysis by mass
spectrometry. To this end, a mass spectrometer is provided that generates
a set of spectra signals that are indicative of the composition of the
sample material under analysis.