Cut 2 cm square piece of Whatman 3MM paper and draw a circle on it with a diameter of ~ 5 mm. Place 500 ng of plasmid in 1 ul of 10 mM Tris, pH 7.6, inside the circle. The circles are drawn first so that cross-contamination will not occur from the pen when shipping several different plasmids. These pieces of paper should then be placed into sealable bags and heat sealed so that if the envelope gets wet, the plasmid being sent will not wash away or become cross-contaminated. Plasmids can then be sent by mail.
For plasmid recovery, cut the circle out, add 50 ul of 10 mM Tris, pH 7.6, vortex and let rehydrate for 5 min. Quick spin, the supernatant liquid can then be used to transform competent bacteria.
Packets of dried plasmid can be stored at 4 oC for several months without loss of competent plasmid.
From G.J. Rosman and D.A. Miller, Biotechniques