Publications & Reports

Near-infrared light-responsive liposomes for protein delivery: Towards bleeding-free photothermally-assisted thrombolysis.

Refaat A, Del Rosal B, Palasubramaniam J, Pietersz G, Wang X, Moulton SE, Peter K


Smart drug delivery systems represent state-of-the-art approaches for targeted therapy of life-threatening diseases such as cancer and cardiovascular diseases. Stimuli-responsive on-demand release of therapeutic agents at the diseased site can significantly limit serious adverse effects. In this study, we engineered a near-infrared (NIR) light-responsive liposomal gold nanorod-containing platform for on-demand delivery of proteins using a hybrid formulation of ultrasmall gold nanorods (AuNRs), thermosensitive phospholipid (DPPC) and non-ionic surfactant (Brij 58). In light-triggered release optimization studies, 55.6% (+/-4.8) of a FITC-labelled model protein, ovalbumin (MW 45kDa) was released in 15min upon NIR irradiation (785nm, 1.35W/cm(2) for 5min). This platform was then utilized to test on-demand delivery of urokinase-plasminogen activator (uPA) for bleeding-free photothermally-assisted thrombolysis, where the photothermal effect of AuNRs would synergize with the released uPA in clot lysis. Urokinase light-responsive liposomes showed 80.7% (+/- 4.5) lysis of an in vitro halo-clot model in 30min following NIR irradiation (785nm, 1.35W/cm(2) for 5min) compared to 36.3% (+/- 4.4) and 15.5% (+/- 5.5) clot lysis from equivalent free uPA and non-irradiated liposomes respectively. These results show the potential of low-dose, site-specific thrombolysis via the combination of light-triggered delivery/release of uPA from liposomes combined with photothermal thrombolytic effects from gold nanorods. In conclusion, newly engineered, gold nanorod-based, NIR light-responsive liposomes represent a promising drug delivery system for site-directed, photothermally-stimulated therapeutic protein release.

Link to publisher’s web site


  • Journal: Journal of Controlled Release
  • Published: 17/07/2021
  • Volume: 337
  • Pagination: 212-223