A dye or other colorimetric substance may be added to the catalyst solution to allow for visualization of the amount and {HEAD ~ location} of {TAIL ~ catalyst solution} on the substrate 
A dye or other colorimetric substance may be added to the catalyst solution to allow for visualization of the amount and { HEAD ~ location } of { TAIL ~ catalyst solution } on the substrate
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH