Firmly anchored photosensitizer Chlorin e6 to layered double hydroxide nanoflakes for highly efficient photodynamic therapy in vivo

Abstract

In using nanomaterials for advanced photodynamic therapy, it is important to improve surface modification to increase stability, minimize non-specific loss of drugs in blood circulation, enhance the photostability of photosensitizers, and achieve highly efficient intracellular uptake. In this report, we for the first time covalently conjugate photosensitizer Chlorin e6 (Ce6) to polyethylene glycol modified layered double hydroxides and produce hybrid nanoflakes. These nanoflakes display many superior characteristics and lead to excellent in vivo photodynamic therapeutic efficiency and safety profiles.

Photophysics of chlorin e6: from one- and two-photon absorption to fluorescence and phosphorescence

“…0.3 eV is found by our simulations, probably due to a non-perfect description of the solvent relaxation. 40 Because of the consistent uorescence intensityand the difficulties in measuring phosphorescencein biological and nanomaterials applications of Ce6 and porphyrin derivatives, [69][70][71] it seems unlikely that the emission is due to phosphorescence, and should rather be assigned to the emission from the singlet manifold. This aspect can be ascribed to two factors, rst a non-unitary population of the triplet manifold should be taken into account, leading to a signicant residual population of the singlet manifold, that can relax and lead to emission.…”

<p>Chlorins e6 loaded silica nanoparticles coated with gastric cancer cell membrane for tumor specific photodynamic therapy of gastric cancer</p>

“…Photodynamic therapy (PDT) is a rapidly developing technic that employ photodynamic agents to transfer NIR light into highly ROSto exert cytotoxic on cells 19. As a noninvasive and harmless approach, PDT is well recognized as a preferable measure for cancer therapy 20.…”

Luminescent CaTiO3:Yb,Er nanofibers co-conjugated with Rose Bengal and gold nanorods for potential synergistic photodynamic/photothermal therapy

“…11 To date, a variety of ultraviolet light or visible light responsive photosensitizers including Ce6 (660 nm) and Photofrin (630 nm) have been investigated. [18][19][20] In such regions of the electromagnetic spectrum, light penetration is hindered due to endogenous chromophores and light scattering. 21 Therefore, two or more separate spectra with different wavelengths would normally be utilized for sequential excitation of each therapeutic step because of the absorption mismatch between photosensitizers and photothermal agents.…”