A method of forming a printing pin includes providing a printing pin having an exterior surface and an interior surface that defines a lumen or capillary tract. The pin is treated to render the exterior and interior surfaces hydrophilic. The lumen or capillary tract is filled with a blocking material. The exterior surface of the pin is coated with a hydrophobic material. The blocking material is then removed. The method produces a pin with selective wetting properties. The modified pins reduce solution or reagents use because no excess liquid is picked up on the exterior surface during loading. As a result, no pre-printing operation is needed to remove this excess liquid. Because no pre-printing operation is needed, the pins produce shorter printing times. In addition, due to improved control of liquid loading volume, it is possible to obtain smaller spots as well as more spots in a given run.