A medical needle may include a lumen coating configured to reduce surface energy of the lumen-facing/lumen defining surface, in a manner effective to slow and/or reduce coagulation of biomaterial (particularly blood) that contacts the needle lumen surface. Such a coating may include a hydrophobic coating such as a silane and/or siloxane material on at least the needle lumen surface. The coating reduces a surface energy of coated needle regions below the surface energy of uncoated regions, and particularly reduces the polar component of the surface energy in the coated needle regions. The needle may be a metallic biopsy needle with the coating comprised by at least a distalmost length of sample-collection lumen.
