Fabrication of Fe(III)-doped mesoporous silica nanoparticles as biocompatible and biodegradable theranostic system for Remdesivir delivery and MRI contrast agent

Coronavirus causes the majority of common colds and is spread in the same way that all viruses attack the respiratory system. Despite the trials and efforts to produce a suitable vaccine, there are solutions for the quick, effective and efficient use of existing drugs to prevent infections and improve the condition of patients. In this study, we synthesized mSiO(2) NPs doped with Fe(III) (Fe(III)-mSiO(2)) and loaded with Rd, and then the NPs coated with PDA as gatekeeper. The several surface methods successfully approved fabrication of the nanosystem. Finally, the application of nanosystem as theranostic system was studied. The DLS measurements showed the average sizes of 115 ± 2 and 124 ± 3.6 nm for Fe-SiO(2) and Fe-SiO(2)@PDA NPs, respectively, suitable for theranostic intentions. The drug release experiments, the in-vitro MRI measurements and MTT test were accomplished, respectively, to show applicability of the nanosystem as a biodegradable Rd delivery system, MRI contrast agent, and the biocompatibility nanocarrier. The results achieved through in-vitro tests exhibited that the Fe-SiO(2) system has potential application as a contrast agent in MRI with relaxivity (r(1)) of 14 ± 1 mM(−1) s(−1). The Rd drug was released from the Fe-SiO(2)(Rd)(load)@PDA system more efficient and faster than SiO(2)(Rd)(load)@PDA at 7.4, supporting the doping of Fe in SiO(2) induces a biodegradability feature in that. The in-vitro biocompatibility studies showed that the Fe-SiO(2) NPs (without drug) is not toxic.