Supercritically dried superparamagnetic mesoporous silica nanoparticles for cancer theranostics

• Published in: Materials Science & Engineering C 2020-10, Vol.115, p.111124, Article 111124
• Main Authors: Vaz-Ramos, Joana, Cordeiro, Rosemeyre, Castro, M. Margarida C.A., Geraldes, Carlos F.G.C., Costa, Benilde F.O., Faneca, Henrique, Durães, Luísa
• Format: Article
• Language: English
• Subjects: Aminopropyltriethoxysilane; Antibiotics, Antineoplastic - chemistry; Antibiotics, Antineoplastic - pharmacology; Cancer theranostics; Cell Proliferation - drug effects; Cell Survival - drug effects; Contrast agents; Contrast media; Core-shell nanoparticles; Cytotoxicity; Drug carriers; Drug delivery; Drug Delivery Systems; Drying; Epirubicin; Epirubicin - chemistry; Epirubicin - pharmacology; Hep G2 Cells; Humans; Iron oxide; Iron oxides; Magnetite Nanoparticles - chemistry; Materials science; Mesoporous silica; MRI contrast agent; Nanoparticles; NMR; Nuclear magnetic resonance; Particle Size; Platforms; Porosity; Precision Medicine; Silica; Silicon dioxide; Silicon Dioxide - chemistry; Sol-gel processes; Supercritical fluids; Thermal decomposition; Toxicity
• ISSN: 0928-4931; 1873-0191
• DOI: 10.1016/j.msec.2020.111124

Mesoporous silica nanoparticles with a superparamagnetic iron oxide core were prepared in this work, in order to obtain multifunctional platforms with adequate features for cancer theranostics. Three different core-shell nanocomplexes were obtained: IO-OAm/mSiO2, IO-APTES/mSiO2 and IO/SiO2/mSiO2. In the case of IO-OAm/mSiO2 and IO-APTES/mSiO2, iron oxide (IO) was obtained by thermal decomposition, having in this case a coating of oleylamine (OAm) that was in the second formulation exchanged by (3-aminopropyl)triethoxysilane ligand (APTES). Regarding the IO/SiO2/mSiO2 formulation, iron oxide was synthesized by microemulsion. The mesoporous silica shell (mSiO2) on the IO nanoparticles was obtained by sol-gel and the final materials were dried by supercritical fluids drying. VSM confirmed the superparamagnetic behaviour of the nanoparticles, leading to MS of 4.0, 1.8 and 10.2 emu·g−1, for IO-OAm/mSiO2, IO-APTES/mSiO2 and IO/SiO2/mSiO2, respectively. NMR relaxometry has shown the potential of these nanoparticles to be used as T2 contrast agents, with r2 values as high as 63.93 s−1·mM−1 Fe. The three types of nanoparticles exhibited loading contents of epirubicin of ~3% and drug release percentages of 19% for IO-OAm/mSiO2, 24% for IO-APTES/mSiO2 and 31% for IO/SiO2/mSiO2. The cytotoxicity of drug-loaded and non-loaded most promising nanoparticles was assessed, showing high potential of these platforms for application as anticancer drug carriers. [Display omitted] •Superparamagnetic iron oxide/mesoporous SiO2 core-shell nanoparticles are prepared.•New ligand exchange and supercritical fluids drying approaches were applied.•Higher % of released epirubicin compared to the literature: up to 30% after 48 h•Potential as T2 contrast agents for MRI, with r2 as high as 63.93 s−1·mM−1 Fe.•Promising biocompatible multifunctional platforms for cancer theranostics