UV-C driven reduction of nanographene oxide opens path for new applications in phototherapy

• Type: Article in International Scientific Journal
• Date: 2024

Authors

Silva, FALS (Author) Other; Timochenco, L (Author) Other; Costa Almeida, R (Author) Other; Fernandes, JR (Author) Other; Santos, SG (Author) Other; Magalhães, F. D. (Author) FEUP; Artur Pinto (Author) FEUP

Journal

Title: Colloids and Surfaces B: Biointerfaces

Vol. 233

ISSN: 0927-7765

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 4 Citations

Scopus - 4 Citations

Other information

Authenticus ID: P-00Z-GHR

DOI: 10.1016/j.colsurfb.2023.113594

Abstract (EN): The main challenges associated to the application of graphene-based materials (GBM) in phototherapy are obtaining particles with lateral nanoscale dimensions and water stability that present high near-infrared (NIR) absorption. Nanosized graphene oxide (GOn) is stable in aqueous dispersion, due to the oxygen functionalities on its surface, but possesses low photothermal efficiency in NIR region. GOn total reduction originates reduced nanographene oxide (rGOn) that presents high NIR absorption, but poor water stability. In this work, we produced a partially reduced nanographene oxide (p-rGOn) by GOn photoreduction using ultraviolet radiation (UVC), yielding nanometric particles that preserve the original water stability, but acquire high light-to-heat conversion efficiency. GOn and p-rGOn presented mean particle sizes of 170 +/- 81 nm and 188 +/- 99 nm, respectively. 8 h of UV-C irradiation allowed to obtain a p-rGOn stable for up 6 months in water, with a zeta potential of -32.3 +/- 1.3 mV. p-rGOn water dispersions have shown to absorb NIR radiation, reaching 52.7 degrees C (250 mu g mL-1) after 30 min NIR irradiation. Chemical characterization of p-rGOn showed a decrease in the number of characteristic oxygen functional groups, confirming GOn partial reduction. Furthermore, p-rGOn (250 mu g mL-1) didn't cause any cytotoxicity (ISO10993-5:2009(E)) towards human skin fibroblasts (HFF-1) and human skin keratinocytes (HaCat), after 24 and 48 h incubation. An innovative custom-built NIR LED-system has been developed and validated for p-rGOn photothermal effect evaluation. Finally, exposure to p-rGOn+NIR-LEDs has caused no cytotoxicity towards HFF-1 or HaCat cells, revealing its potential to be used as a safe therapy.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 11