Silica coated Bi$_2$Se$_3$ topological insulator nanoparticles : an alternative route to retain their optical properties and make them biocompatible

Belec, Blaž (author), Kostevšek, Nina (author), Della Pelle, Giulia (author), Nemec, Sebastjan (author), Kralj, Slavko (author), Bergant Marušič, Martina (author), Gardonio, Sandra (author), Fanetti, Mattia (author), Valant, Matjaž (author)

Localized surface plasmon resonance (LSPR) is the cause of the photo-thermal effect observed in topological insulator (TI) bismuth selenide (Bi$_2$Se$_3$) nanoparticles. These plasmonic properties, which are thought to be caused by its particular topological surface state (TSS), make the material interesting for application in the field of medical diagnosis and therapy. However, to be applied, the nanoparticles have to be coated with a protective surface layer, which prevents agglomeration and dissolution in the physiological medium. In this work, we investigated the possibility of using silica as a biocompatible coating for Bi$_2$Se$_3$ nanoparticles, instead of the commonly used ethylene-glycol, which, as is presented in this work, is not biocompatible and alters/masks the optical properties of TI. We successfully prepared Bi$_2$Se$_3$ nanoparticles coated with different silica layer thicknesses. Such nanoparticles, except those with a thick, ≈200 nm silica layer, retained their optical properties. Compared to ethylene-glycol coated nanoparticles, these silica coated nanoparticles displayed an improved photo-thermal conversion, which increased with the increasing thickness of the silica layer. To reach the desired temperatures, a 10–100 times lower concentration of photothermal nanoparticles was needed. In vitro experiments on erythrocytes and HeLa cells showed that, unlike ethylene glycol coated nanoparticles, silica coated nanoparticles are biocompatible.

• Language: English
• Keywords: topological insulator, bismuth selenide, photo-thermal materials, biocompatibility, nanoparticles
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FFA - Faculty of Pharmacy
• Publication status: Published
• Publication version: Version of Record
• Year: 2023
• Number of pages: 14 str.
• Numbering: Vol. 13, iss. 5, art. 809
• PID: 20.500.12556/RUL-155614
• UDC: 53
• ISSN on article: 2079-4991
• DOI: 10.3390/nano13050809
• COBISS.SI-ID: 142713091
• Publication date in RUL: 08.04.2024

Record is a part of a journal

• Title: Nanomaterials
• Shortened title: Nanomaterials
• Publisher: MDPI AG
• ISSN: 2079-4991
• COBISS.SI-ID: 523286297

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• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.