In this paper, we used microcapsules releasing liposome-protamine-hyaluronic acid nanoparticles (LPH-NP) with/without carboplatin in response to radiation to image and treat MM48 breast cancer in C3He/N mice in two radiation sessions. The micro-particle-induced X-ray emission (PIXE) camera and quantitative PIXE were used to image and measure the release of nanoparticles from the microcapsules. In session one, iopamiron and computed tomography (CT)-detectable microcapsules containing P-selectin and LPH-NP were mixed with a solution of alginate, hyaluronate, ascorbate, and P-selectin. This solution was sprayed into an FeCl2 solution containing VEGFR-1/2 antibodies (Abs). The microcapsules obtained were injected intravenously into mice, and after 9 h, the mice were exposed to 10 or 20 Gy (140 keV) of X-ray radiation. Anti-VEGFR-1/VEGFR-2 microcapsules accumulated around tumors and released P-selectin and the iopamiron-labeled LPH-NP in response to the first radiation. The iopamiron-containing nanoparticles were detected by CT, allowing detection of MM48 tumors by CT. In the second session, the microcapsules released LPH-NH that delivered carboplatin into the tumor cells. This treatment had a significant antitumor effect [Formula: see text]. The micro-PIXE camera and quantitative PIXE successfully imaged and measured the release of contents from microcapsules. Our results indicate that targeted nanoparticles allow for accurate detection and treatment of tumors.