Functionalisation of TiO2 nanoparticles with a fluorescent organosilane: A synergy enabling their visualisation in biological cells and an enhanced photocatalytic activity

Colloids Surf B Biointerfaces. 2019 Sep 1:181:1019-1025. doi: 10.1016/j.colsurfb.2019.05.060. Epub 2019 May 30.

Abstract

Nanoparticles, such as TiO2 particles, have a great potential for biomedical applications due to their ultra-small size and large specific surface area. However, their detection within cells is to date more than challenging. Thus, implementing fluorescence properties to nanoparticles via their controlled functionalisation with an organic chromophore is an original and efficient strategy to enable their visualization. In this work, a silylated coupling agent bearing a luminescent rhodamine B group was synthesised and grafted on the surface of anatase nanoparticles. The successful functionalisation was demonstrated via zeta potential, dynamic light scattering and diffuse reflectance infrared Fourier transform analyses. Remarkably, the obtained luminescent TiO2 particles showed an improved photocatalytic activity compared to the pristine nanoparticles. Both, as-synthesised and functionalised TiO2 nanoparticles samples appear to be non-toxic towards malignant and non-malignant cells. Moreover, the detection of the functionalised particles within cultured cells was proven to be easy and efficient via confocal fluorescence microscopy.

Keywords: Cell labelling; Confocal fluorescence microscopy; Cytotoxicity; Luminescence; Silylated coupling agent; TiO(2) nanoparticles.

MeSH terms

  • Biomedical Research
  • Catalysis
  • Fluorescence*
  • Microscopy, Confocal
  • Microscopy, Fluorescence
  • Nanoparticles / chemistry*
  • Organosilicon Compounds / chemical synthesis
  • Organosilicon Compounds / chemistry*
  • Particle Size
  • Photochemical Processes*
  • Rhodamines / chemistry
  • Surface Properties
  • Titanium / chemistry*

Substances

  • Organosilicon Compounds
  • Rhodamines
  • titanium dioxide
  • Titanium
  • rhodamine B