Fig. 2
High-speed and high-ratio swelling of the ingestible hydrogel device. a Time-lapse images of the hydrogel device swelling in water (pH 7). b Volume changes of the hydrogel device (membrane modulus 3 kPa), air-dried hydrogel, and freeze-dried hydrogel of the same size as a function of swelling time in water. c Comparison of the swelling ratios and speeds in water between the hydrogel device in current work and previously reported hydrogels10,20,21,46. d Volume changes of the hydrogel devices with various membrane moduli as functions of swelling time in water. e Volume changes of the hydrogel devices (membrane modulus 3 kPa) as functions of swelling time in porcine gastric fluid and SGF (pH 3). f Swelling ratios of the hydrogel devices with various membrane moduli in water, SGF (pH 3), and porcine gastric fluid. g Swelling speeds of the hydrogel devices with various membrane moduli in water, SGF (pH 3), and porcine gastric fluid. Scale bars are 10 mm in (a). Data represent the mean ± s.d. (N = 3)
