Fig. 6. Demonstration of the therapeutic potential of a thick SONIC device.

a, b Schematics representing the simulated geometry for a thick control device (a) and thick SONIC device (6.6 × 6.6 × 6.6 mm) (b) containing rat islets (size-distributed). Simulation-predicted pO₂ distributions of the control device in three cross-sections (labeled A-A, B-B, and C-C) showing a massive hypoxic central region, with necrosis observed even in some small islets (arrows in C-C cross-section). However, the islets were well-oxygenated throughout the SONIC device with negligible necrosis. c, d Average pO₂ (c) and the fraction of necrosis (d) in the islet populations in control devices (n = 20) and SONIC devices (n = 20) at the size of 4.2 mm and 6.6 mm, mean ± SD. e, f Scatter plots of islet location versus average pO₂ of islets (generated as all 150 µm in diameter) in the thick control device (e) and thick SONIC device (f). g, h Schematic (g) and microscope image (h) of rat islets encapsulated in a thick cubic SONIC device with a side length of ~6.6 mm. One representative of 5 replicates is shown. i BG measurements of diabetic C57BL6/J mice following IP transplantation of the 6.6 mm SONIC devices (pink, n = 5, retrieved on day 60; red, n = 5, retrieved on day 123). j IPGTT on day 58; mean ± SD; **p = 0.0066 (two-way ANOVA). k Live/dead staining of islets from a retrieved device on day 120. l, m H&E (l) and immunohistochemical staining (m) of retrieved devices on day 120 showing morphology-intact and insulin/glucagon-positive islets. One representative of 5 replicates is shown.