Figure 2.

3D-printed multimaterial gastric-residence architecture prototype (GRA) and electronics (GRE). A) Schematic of the computer-aided design model of the 3D-printed multimaterial architecture. Left inset image shows the optical photograph of a 3D-printed multimaterial GRA and right inset is an X-ray image indicating the relative location of metal probes embedded in the GRA of the in vivo gastric residence study. B) High-speed camera imaging series showing the expansion of 3D-printed architecture (i) before, (ii) during, and (iii) after expansion. C) X-ray image shows the gastric residence of a control prototype demonstrating the maximum gastric residence of 4 d without a gastric residence architecture. D) In contrast, GRA permits gastric residence for up to 24 d, as shown in the X-ray image. The structure will subsequently disintegrate by detachment. First, one of the GRA arm is detached, as indicated by the metal probes at day 27. (The top inset image shows the detached arm that has been passed to the intestinal region, while the remaining structure stays in the gastric space.) Second, at day 30, both GRA arms are detached, allowing the GRA to pass between day 31 and day 33. E) GRE exhibited a similar disintegration as GRA where at day 24, one of the prototypes began to lose one of the gastric residence structure, before both gastric residence arms are detached. F) In another GRE, a maximum gastric residence of 36 d was achieved. G) Statistical comparison of device residence period of a structure without GRA (control), GRA prototype, and ultimately GRE, demonstrating the effectiveness of GRA in prolonging gastric residence.