The method involves the application of focused acoustic energy to each of a plurality of fluid containing reservoirs to eject a small fluid droplet on the order of 1 picoliter or less from each reservoir to {TAIL ~ a site} on {HEAD ~ a porous substrate surface} 
The method involves the application of focused acoustic energy to each of a plurality of fluid containing reservoirs to eject a small fluid droplet on the order of 1 picoliter or less from each reservoir to { TAIL ~ a site } on { HEAD ~ a porous substrate surface }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD