title: Polymer-Grafted Mesoporous Silica Nanoparticles as Ultrasound-Responsive Drug Carriers.
abstract: A new ultrasound-responsive system based on mesoporous silica nanoparticles was developed for biomedical applications, grafting a copolymer on their surface that acts as gatekeeper of the pores. The nanoparticles can be loaded with a cargo at low temperature (4 °C), taking advantage of the open conformation that the polymer presents under these conditions. Then, at 37 °C the copolymer collapses closing the pore entrances and allowing the nanoparticles to carry the drugs at physiological temperature without premature release, which is of great importance when dealing with cytotoxic drugs in cancer treatments. Upon ultrasound irradiation, the sensitive polymer changes its hydrophobicity and, therefore, its conformation toward coil-like opening the gates and releasing the cargo. These hybrid nanoparticles have been shown to be noncytotoxic and can be internalized into LNCaP cells retaining their ultrasound-responsive capability in the cytoplasm of the cells. Moreover, doxorubicin-loaded hybrid MSNs were incubated with LNCaP cells to show their capacity to induce cell death only when the nanoparticles had been exposed to ultrasound. This work demonstrates that our hybrid-MSNs can be triggered by remote stimuli, which is of capital importance for future applications in drug delivery and cancer therapy.
authors.affiliation: Dpto. Química Inorgánica y Bioinorgánica, Facultad de Farmacia, UCM , Instituto de Investigación Sanitaria Hospital 12 de Octubre i+12, 28040 Madrid, Spain.|Centro de Investigación Biomédica en Red de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN) , 50018 Zaragoza, Spain.
authors.forename: Juan L
authors.initials: JL
authors.lastname: Paris
authors.affiliation: Dpto. Química Inorgánica y Bioinorgánica, Facultad de Farmacia, UCM , Instituto de Investigación Sanitaria Hospital 12 de Octubre i+12, 28040 Madrid, Spain.
authors.forename: M Victoria
authors.initials: MV
authors.lastname: Cabañas
authors.affiliation: Dpto. Química Inorgánica y Bioinorgánica, Facultad de Farmacia, UCM , Instituto de Investigación Sanitaria Hospital 12 de Octubre i+12, 28040 Madrid, Spain.|Centro de Investigación Biomédica en Red de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN) , 50018 Zaragoza, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Manzano
authors.affiliation: Dpto. Química Inorgánica y Bioinorgánica, Facultad de Farmacia, UCM , Instituto de Investigación Sanitaria Hospital 12 de Octubre i+12, 28040 Madrid, Spain.|Centro de Investigación Biomédica en Red de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN) , 50018 Zaragoza, Spain.
authors.forename: María
authors.initials: M
authors.lastname: Vallet-Regí
mesh_terms: D016923:Cell Death; D045744:Cell Line, Tumor; D004337:Drug Carriers / Q000737:chemistry*; D000067493:Dynamic Light Scattering; D019793:Fluorescein / Q000737:chemistry; D006801:Humans; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D011108:Polymers / Q000737:chemistry*; D016062:Porosity; D012822:Silicon Dioxide / Q000737:chemistry*; D013696:Temperature; D014465:Ultrasonics
chemical_list: D004337:Drug Carriers; D011108:Polymers; D012822:Silicon Dioxide; D019793:Fluorescein
keywords: drug delivery; mesoporous silica; nanomedicine; stimuli-responsive; ultrasound