Gold-loaded liposomes with photosensitizers for PDT

2 February 2017:

A new publication from CNBP researchers Wei Deng (pictured), Sandhya Clement and Ewa Goldys indicates that gold-loaded liposomes incorporating photosensitizers may serve as improved agents in photodynamic therapy and chemotherapy. The work has just been reported in the International Journal of Nanomedicine and is accessible online.

Journal: International Journal of Nanomedicine.

Title: Light-triggered liposomal cargo delivery platform incorporating photosensitizers and gold nanoparticles for enhanced singlet oxygen generation and increased cytotoxicity

Authors: Zofia Kautzka, Sandhya Clement, Ewa M Goldys and Wei Deng.

Abstract: We developed light-triggered liposomes incorporating 3–5 nm hydrophobic gold
nanoparticles and Rose Bengal (RB), a well-known photosensitizer used for photodynamic
therapy. Singlet oxygen generated by these liposomes with 532 nm light illumination was
characterized for varying the molar ratio of lipids and gold nanoparticles while keeping
the amount of RB constant. Gold nanoparticles were found to enhance the singlet oxygen
generation rate, with a maximum enhancement factor of 1.75 obtained for the molar ratio of hydrogenated soy l-α-phosphatidylcholine:1,2-dioleoyl-sn-glycero-3-hosphoethanolamineN-(hexanoylamine): gold of 57:5:17 compared with liposomes loaded with RB alone. The experimental results could be explained by the local electric field enhancement caused by gold nanoparticles. We further assessed cellular cytotoxicity of gold-loaded liposomes by encapsulating an antitumor drug, doxorubicin (Dox); such Dox-loaded liposomes were applied to human colorectal cancer cells (HCT116) and exposed to light. Gold-loaded liposomes containing RB and Dox where Dox release was triggered by light were found to exhibit higher cytotoxicity compared with the liposomes loaded with RB and Dox alone. Our results indicate that goldloaded liposomes incorporating photosensitizers may serve as improved agents in photodynamic therapy and chemotherapy.