Research Highlight

Going with the flow: Laser heat removes blood clots

doi:10.1038/nindia.2016.128 Published online 29 September 2016

Researchers have developed a photothermal therapy to remove blood clots by generating laser-induced-heat through gold nanorods.1 Combined with a low-dose clot-busting drug, the therapy is a potential tool for alleviating various cardiovascular diseases and blood-clot-related disorders.

Clots can cause cerebral stroke and cell death in heart muscle tissues by blocking the flow in major arteries that carry blood to the brain and the heart. Current clot-busting drugs can trigger life-threatening bleeding and even stroke. 

Researchers, from the Banaras Hindu University, Varanasi, developed the photothermal therapy that generates heat by exposing gold nanorods to near-infrared laser. They then tested its efficiency in removing blood clots in mice.   

When exposed to laser for 45 minutes, the nanorods ablated blood clots made from platelet-poor plasma. Combination of laser-exposed nanorods and a low-dose clot-busting drug streptokinase reduced the size of a newly developed clot more efficiently than an aged clot. 

In mice, laser therapy in combination with a low-dose streptokinase cleared blood clots more efficiently than laser therapy alone. Laser exposure produced temperatures that did not harm the blood vessel wall in mice.

“Since the near-infrared laser can penetrate up to a depth of 10 cm, it can clear blood clots in superficial veins and restore blood flow in them,” says lead researcher Debabrata Dash.


1. Singh, N. et al. Relief from vascular occlusion using photothermal ablation of thrombus with a multimodal perspective. Nano. Res.  9, 2327–2337 (2016)