Gold Nanoparticle-assisted Selective Photothermolysis of Adipose Tissue (NanoLipo)

Background: Conventional suction-assisted lipectomy (SAL) often results in contour irregularity. Selective photothermal heating of adipose tissue by polymer-coated gold nanorods energized by an external near-infrared exposure at 800 nm is introduced in this work to facilitate fat removal. Methods: The effects of NanoLipo were examined in food-grade porcine abdominal tissue (skin, fat, and fascia) by histology. The efficacy of NanoLipo was compared with that of conventional SAL in vivo in Yucatan mini pigs by quantification of removed subcutaneous tissue and fatty acids and ultrasound measurement of adipose layer thickness. Results: NanoLipo led to the appearance of disruptions in adipose tissue that were not apparent in control groups in ex vivo samples. NanoLipo allowed removal of more subcutaneous tissue (similar to 33% vs similar to 25% of removed material, P < 0.05) and approximately twice as much free fatty acids (similar to 60% vs similar to 30% of removed tissue, P < 0.05) in comparison with conventional SAL. Most importantly, NanoLipo led to a greater decrease in adipose layer thickness at 1 month post surgery (P < 0.001). Conclusions: NanoLipo facilitates removal of a greater quantity of fat and requires less suction time (4 vs 10 minutes) than conventional SAL. As the safety of poly(ethylene-glycol)-coated gold nanorods is well-established, a clinical trial is currently being organized.