Non-invasive Imaging of Gastric Iron Delivery

The same mice as above were used and subjected to the same acclimatization procedures. Mice were randomly selected from cages for all experiments. Mice were randomly divided into two groups (n = 3), both orally administered with 100 µL Fe‐CDs (2 mg mL⁻¹), and fed after 10 min. Then, one group was orally administered 50 µL Omeprazole (OMG) water solution (20 mg mL⁻¹), and the other group was orally administered 50 µL water. NIR imaging of mice was conducted at different times following feeding. For non‐invasive imaging, all mice were anesthetized using a rodent ventilator with 2 L min⁻¹ air mixed with 4% isoflurane, and imaging was performed at the left lateral aspect of the mouse abdomen. For invasive imaging, mice were sacrificed and dissected along the upper part of the abdomen. The stomach was exposed outside of the abdomen for imaging. For gastric fluid imaging, the excised stomachs were cut open along the greater curvature, excess gastric content was removed, and imaging was performed on the inner wall of the stomach. The excitation source was provided by an 808 nm diode laser with a fluence rate of ≈200 mW cm⁻², and the emission signals were collected at 1000 nm with an exposure time of 50 ms. Ratio images were processed using Matlab software, and average ratios were taken from the same region of interest in various images.