To obtain a five-centimeter long glass well, using one hand, firmly grasp the glass tube cutter tool by its handle. On the other hand, hold the glass tube and rotate it continuously so that the wheels in the chain start cutting the glass. Gently squeeze the tool by gradually increasing the pressure on the handles.
Use 120 grit sandpaper to smoothen the broken end of the glass well. Then polish with 220 grit sandpaper. To attach the cut glass well to the surface of the substrate, dispense two part epoxy resin onto a small sheet of aluminum foil.
Blend the product using a stir stick or a pipette tip. Then, apply the mixture to the bottom rim of the glass well. Glue the glass well to the surface of the gap-mode substrate.
Then, apply the remaining mixed product on the outside of the well where it meets the substrate. To attach the electrical connection to the gap-mode SERS substrate, mix two part conductive epoxy resin onto a small sheet of aluminum foil using a five centimeter long copper wire. Attach the wire to the surface of the substrate.
