Fig. 6: In vivo biodistribution of nanoparticles after oral administration.

a Schematic illustration of nanoparticle adsorption to the CRC-intestinal segment. b Representative fluorescence images of digestive tracts and major tissues at various time points post-oral administration of different nanoparticles. The white circles idenote the CRC location. S means stomach; Li means liver; H means Heart; Sp means spleen; Lu means lung; K means kidney. c Quantitative analysis of fluorescence intensity in the CRC intestinal segment of mice at different time points after oral administration (n = 3 independent experiments). d Quantitative analysis of fluorescence intensity in major tissues 24 h post-oral administration (n = 3 independent experiments). e Analysis of the Si element at the CRC sites of mice at different time points after oral administration (n = 3 independent experiments). f Analysis of the Si element in major tissues 24 hours after oral administration (n = 3 independent experiments). g TEM images showing the distribution of different nanoparticles in the intestinal loop and villi after 5 min of intestinal circulation. h Average number of nanoparticles in TEM images of intestinal loop and villi (n = 3 independent experiments). i Fluorescence images displaying changes in ZO-1 protein expression (j) and nanoparticle fluorescence intensity (k) in mouse colon tissue after 5-min incubation with different nanoparticles (n = 3 independent experiments). l Changes in the width of tight junctions in mouse colon tissues after 5-min incubation with different nanoparticles (n = 3 independent experiments). m Fluorescence intensity changes in the basal chamber after different nanoparticles were incubated with Caco-2 cells and then co-incubated with GFP-Escherichia coli 1917 in the apical chamber for 2 h (n = 3 independent experiments). Data are presented in the form of mean values ± SD. Significance was assessed using one-way ANOVA with Tukey’s post hoc test. Source data are provided as a Source Data file.