Fig. 3: Ex vivo demonstration of the BioUCT.

a The BioUCT adhered to the ex vivo small intestine can withstand high pulling force and maintain robust adhesion to the small intestine. The scale bar is 10 mm. b Interfacial toughness between the bioadhesive hydrogel and porcine small intestine measured within 48 h after adhesion formation. Data are presented as mean ± SD. Each data point represents the mean of n independent samples (n = 3). Error bars indicate standard deviation (± SD) of the weight ratio. c Ultrasound contrast imaging of ex vivo intestine (left image). The scale bar in the ultrasound image is 2 cm. The brightness of the intestine (right image) is improved by 33 dB on the ultrasound image using BioUCT. Data are presented as mean ± SD. Each data point represents the mean of n independent tests (n = 3). Error bars indicate ± SD of the brightness. d B-mode ultrasound image (left) and an M-mode ultrasound image (right) for tracking dynamic intestinal motion in an ex vivo test. The scale bar is 5 mm. e The degradation rate of the BioUCT can be adjusted between 10% and 90% degradation in PBS solution (37 °C) within 120 days. Data are presented as mean ± SD. Each data point represents the mean of n independent tests (n = 3). Error bars indicate ± SD of the weight ratio. f Images showing the degradation process of BioUCTs with various degradation rates. The scale bar is 1 mm. g Young’s modulus of BioUCTs with different degradation rates. Data are presented as mean ± SD. Each data point represents the mean of n independent tests (n = 3). Error bars indicate the ± SD of Young’s modulus.