β-Ga2O3:Cr3+ nanoparticle: A new platform with near infrared photoluminescence for drug targeting delivery and bio-imaging simultaneously

Multifunctional nanoparticles which integrate the therapeutic agents and bio-imaging agents into one carrier are emerging as a promising therapeutic platform. Herein, GaOOH:Cr3+ was firstly synthesized using improved hydrothermal method (atmospheric pressure, 95 degrees C), and by manipulating the pH of the reaction medium, GaOOH:Cr3+ with different sizes (125.70 nm, 200.60 nm and 313.90 nm) were synthesized. Then beta-Ga2O3:Cr3+ nanoparticles with porous structures were developed as a result of the calcination of GaOOH:Cr3+. The fabricated, porous beta-Ga2O3:Cr3+ nanoparticles could effectively absorb doxorubicin hydrochloride (DOX) (loading rate: 8% approximately) and had near infrared photoluminescence with a 695 nm emission. Furthermore, beta-Ga2O3:Cr3+ nanoparticles were coated with L-Cys modified hyaluronic acid (HA-Cys) by exploiting the electrostatic interaction and the cross-link effect of disulfide bond to improve the stability. The DOX loaded HA-Cys coated beta-Ga2O3:Cr3+ nanoparticles (HA/beta-Ga2O3:Cr3+/DOX) showed an oxidation-reduction sensitive drug release behavior. The HA-Cys coated beta-Ga2O3:Cr3+ nanoparticles showed a low cytotoxicity on MCF-7 and Hela cell lines. The cellular uptake of HA/beta-Ga2O3:Cr3+/DOX using the near infrared photoluminescence of beta-Ga2O3:Cr3+ nanoparticles and the fluorescence of DOX demonstrated the HA/beta-Ga2O3:Cr3+/DOX could internalize into tumor cells quickly, which was affected by the size and shape of beta-Ga2O3:Cr3+ nanoparticles. (C) 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.