*2.8. Nanaoparticles*

Among the CO-carrying support system, nanoparticles are intensely focused because nanoparticles can passively target the malignant cells and actively involve with the targeted tumor cells. Ulrich Schatzschneider et al. open the gateway for the nanoparticles carriers of Silicium dioxide as photoactivatable CORMats [157]. These research analysts, first time synthesized the 3-azidopropane-functionalized SiO2 nanoparticles, followed by [Mn(CO)3(tpm-L1)] in a dimethylamide solution at room temperature. Manganese-based Photo-CORM [Mn(CO)3(tpm)]+ whose tpm ligand is linked with Silicium dioxide nanoparticles by CuAAC "click" reaction through construction of the Azido group by emulsion copolymerization of (3-azidopropyl)triethoxysilane and trimethoxymethylsilane at the surface. In this mechanism nanoparticles were functionalized with manganese tricarbonyl as light-induced CORMats (Figure 25). SiO2 nanoparticles are stable in nature with an amazing bio-compatibly and easy to modify at the surface. It means that various target molecules could be incorporated at the surface to achieve the drug delivery objectives. Eventually, it will increase the drug delivery capacity at specific sites. So therefore, reduce the systemic risk. To reduce the side effects of chemotherapy, SiO2nanoparticles provide the most valuable platform for tumor drug delivery.

In the nanoparticle carrier strategy, Urara Hasegawa et al. introduced the CO-releasing polymeric nanoparticles (CONPs) through phenylboronic acid-catechol complexation of catechol-bearing CO-donor Ru(CO)3Cl(L-DOPA) and phenylboronic acid-containing framboidal nanoparticles. It has been testified in a biological organism and gives feedback to cysteine, and subdues the pro-inflammatory mediator's IL-6 [168].

**Figure 25.** The mechanism of Manganese tricarbonyl functionalized with silica nanoparticles.
