Hybrid Mesoporous Nanoparticles for pH-Actuated Controlled Release
AbstractAmong a variety of inorganic-based nanomaterials, mesoporous silica nanoparticles (MSNs) have several attractive features for application as a delivery system, due to their high surface areas, large pore volumes, uniform and tunable pore sizes, high mechanical stability, and a great diversity of surface functionalization options. We developed novel hybrid MSNs composed of a mesoporous silica nanostructure core and a pH-responsive polymer shell. The polymer shell was prepared by RAFT polymerization of 2-(diisopropylamino)ethyl methacrylate (pKa ~6.5), using a hybrid grafting approach. The hybrid nanoparticles have diameters of ca. 100 nm at pH < 6.5 and ca. 60 nm at pH > 6.5. An excellent control of cargo release is achieved by the combined effect of electrostatic interaction of the cargo with the charged silica and the extended cationic polymer chains at low pH, and the reduction of electrostatic attraction with a simultaneous collapse of the polymer chains to a globular conformation at higher pH. The system presents a very low (almost null) release rate at acidic pH values and a large release rate at basic pH, resulting from the squeezing-out effect of the coil-to-globule transition in the polymer shell. View Full-Text
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Gonçalves, J.L.M.; Crucho, C.I.C.; Alves, S.P.C.; Baleizão, C.; Farinha, J.P.S. Hybrid Mesoporous Nanoparticles for pH-Actuated Controlled Release. Nanomaterials 2019, 9, 483.
Gonçalves JLM, Crucho CIC, Alves SPC, Baleizão C, Farinha JPS. Hybrid Mesoporous Nanoparticles for pH-Actuated Controlled Release. Nanomaterials. 2019; 9(3):483.Chicago/Turabian Style
Gonçalves, José L.M.; Crucho, Carina I.C.; Alves, Sérgio P.C.; Baleizão, Carlos; Farinha, José P.S. 2019. "Hybrid Mesoporous Nanoparticles for pH-Actuated Controlled Release." Nanomaterials 9, no. 3: 483.
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