Luminescence- and nanoparticle-mediated increase of light absorption by photoreceptor cells: Converting UV light to visible light

Abstract

We developed new optic devices – singly-doped luminescence glasses and nanoparticle-coated lenses that convert UV light to visible light – for improvement of visual system functions. Tb3+ or Eu3+ singly-doped borate glasses or CdS-quantum dot (CdS-QD) coated lenses efficiently convert UV light to 542 nm or 613 nm wavelength narrow-band green or red light, or wide-spectrum white light, and thereby provide extra visible light to the eye. In zebrafish (wild-type larvae and adult control animals, retinal degeneration mutants, and light-induced photoreceptor cell degeneration models), the use of Tb3+ or Eu3+ doped luminescence glass or CdS-QD coated glass lenses provide additional visible light to the rod and cone photoreceptor cells, and thereby improve the visual system functions. The data provide proof-of-concept for the future development of optic devices for improvement of visual system functions in patients who suffer from photoreceptor cell degeneration or related retinal diseases.

Mitochondrial dysfunction in glaucomatous degeneration

“…From the data of the literature, red light across the pupil of rats can enhance the function and survival of RGCs [130] . Red-light therapy can be achieved with a special lens that converts ultraviolet light from the sun into extra red light [131] , which offers a convenient, noninvasive, and painless potential treatment for glaucoma. The limitation of redlight therapy is that the details of the underlying biochemical mechanisms remain to be explored.…”

The utility and risks of therapeutic nanotechnology in the retina

“…80,81 Another area of exploration to treat photoreceptor cell degeneration involves nanoparticle-based light-responsive therapeutics. Examples include cadmium sulfide QD-coated lenses to convert ultraviolet to visible light in zebrafish 97 and the subretinal implant of gold nanoparticle-decorated titania nanowire in mice. 72 XLRS is a leading cause of male macular degeneration involving mutations in the RS1 gene encoding retinoschisin, which causes this protein to be completely absent in the retina in most forms.…”

Comparison of UV-A photolytic and UV/TiO2 photocatalytic effects on Microcystis aeruginosa PCC7813 and four microcystin analogues: A pilot scale study

“…However, the M. aeruginosa cell density could best be represented by a piecewise regression tendency (Figure S6) and significantly rose in the UV/TiO2 treatment over the first eight days with a tendency rate of 0.46 x 10 6 cells mL -1 day -1 (p<0.01), and then decreased after day 8 with a tendency rate of 1 x 10 6 cells mL -1 day -1 (p<0.01; Figure 1C). One possible explanation for this observation is that the TiO2 coated glass beads have converted some of the incoming UV irradiation into visible light through fluorescence from the semiconductor material (Li et al, 2016) in sufficient quantities to support modest growth, despite the fact that ambient overhead light was of low intensity (2.5 µmol photons m -2 s -1 ) and nominally insufficient for significant cell growth evidenced by no growth observed in the treatments without LEDs (Figure 1B).…”