(a) Distribution of ZnMONs containing different numbers of Au15 nanoparticles (the number three means ZnMONs holding three or more Au15 nanoparticles); (b) Comparison of UV-vis absorption of Au15-ZnMON-1 and Au15-ZnMON-2. (c-h) TEM images of ZnMONs assembled with different numbers of multidentate iron oxide nanoparticles (d is the zoom of c; f is the zoom of e; and h is the zoom of g. Compared with Iron oxide11-ZnMON-1, 6 times the number of iron oxide nanoparticles were added to form Iron oxide11-ZnMON-2, and 12 times the number of iron oxide nanoparticles were added to form Iron oxide11-ZnMON-3). Scale bar: c, e, g 100 nm; d, f, h 50 nm.