Devices, assemblies, and methods for delivering a fluid preparation into a gastrointestinal tract

A delivery assembly for an ingestible device for delivering a fluid preparation into a GI lumen wall or surrounding tissue thereof of a subject, the delivery assembly comprising:

• a housing defining a chamber;
• a piston-needle assembly movably disposed in the chamber, the piston-needle assembly comprising an inlet and a channel;
• a membrane coupled to the housing such that the membrane and the housing cooperatively define a reservoir for containing the fluid preparation, wherein the housing further defines an opening extending between the chamber and the reservoir;
• and
• a valve member for selectively controlling a flow of the fluid preparation from the reservoir to the chamber through the opening;
• wherein in response to sufficient movement of the piston-needle assembly relative to the housing, the valve member is structured to open to allow the fluid preparation to flow from the reservoir through the opening into the chamber, the inlet, and the channel for delivery into the GI lumen wall or surrounding tissue thereof.