Researchers at the University of Massachusetts Medical School have developed photodynamic nanoparticles that can effectively target deep-tissue tumors. The team’s work was published in the Journal of the American Chemical Society. 

“This study signals a major step forward in photodynamic therapy by developing a new class of NIR-absorbing biodegradable organic nanoparticles for a highly effective targeting and treatment of deep-tissue tumors,” lead researcher Gang Han said in prepared remarks.

Photodynamic therapy involves dosing a patient with nontoxic light-sensitive drugs, which are absorbed by the body’s cells. A red laser light is then turned on to target the area of the body with a tumor. When the high power laser interacts with the light-sensitive drug, it forms a reactive form of oxygen that can kill malignant cancer cells and leave neighboring cells alone. But tissue penetration depth remains a challenge in photodynamic therapy.

The team of UMass researchers said they have found a way to make the process simpler and more efficient, penetrating further into the tumor tissue.

Han’s team encapsulated carbazole-substituted BODIPY molecules with biodegradable polymers, which then formed small, uniform nanoparticles. With incoherent lamp light, the photodynamic molecules can be tracked throughout the body and deep into the tissue to kill cancerous tumors. The team also reported that the nanoparticles had a long circulating time and could be removed from the body.

The molecules’ properties make them “sufficient to monitor and trigger practical photodynamic therapy effect of these nanoparticles within a wide variety of deep-tissue level tumors such as lung, colon, prostate and breast cancers,” Han said.

The team also suggested that because their method uses a low power lamp light, the method could provide opportunities for precise tumor-targeting theranostics in resource deficient areas.