A system for extracting material from a region of interest includes a fluid delivery base comprising an inlet channel and an outlet channel formed within the fluid delivery base; a gasket affixed to the fluid delivery base, wherein the gasket comprises at least one opening exposing an open end of the inlet channel and an open end of the outlet channel; a support comprising a sample-supporting surface facing the gasket and an opposing surface; and an alignment member coupled to the opposing surface in a fixed position and such that the support is positioned between the fluid delivery base and the alignment member, wherein one or both of the alignment member or the fluid delivery base are biased towards one another by a force (e.g., a magnet or spring force) and wherein the fluid delivery base is separable from the support and configured to move along a plane of the sample-supporting surface to align with the alignment member.