A liquid injection port including a liquid input block defining a liquid input conduit; a compression block adapted to mate with the liquid input block; and a septum including a deformable material mounted in a septum retainer, the septum defining a central perforation, and forming a seal between the liquid input block and the compression block. The septum defines a conical deformation toward the liquid input conduit. A method for delivering fluid from a pipette tip includes a) introducing the fluid into the pipette tip; b) inserting the pipette tip into a pipette conduit defined by a compression block; c) inserting the pipette tip through a septum mounted in the compression block; and d) releasing the fluid in the pipette tip into a liquid input conduit defined in a liquid input block, the septum defining a conical deformation toward the liquid input conduit while maintaining a seal.