Breast cancer is one of the Top 10 causes of death among women worldwide. Although treatment methods have improved, detecting and treating metastases of cancer in lymph nodes remains a challenge. Currently doctors use methylene blue dye to identify where the tumors aggregate in lymph nodes. However, the dye can cause skin lesions.
Members of Dipanjan Pan’s research group at Illinois are addressing this issue by developing a biocompatible nanoparticle, which will not cause any toxic side effects. Their findings have been published in the paper, Biodegradable Biliverdin Nanoparticles for Efficient Photoacoustic Imaging, in the journal ACS Nano.
“By developing nanoparticles that are completely degradable, we hope to provide a tool that can be used for biomedical imaging and cancer therapy,” said Parinaz Fathi, first author of the paper and a Bioengineering Ph.D. student in the lab.
The lab’s biodegradable nanoparticles are made by linking together biliverdin molecules. Biliverdin is a pigment molecule present in the body. Therefore, the body is capable of breaking it down completely. Additionally, biliverdin can give a strong signal that can be easily detected.
“Our goal was to develop an agent that lights up within the body and then disappears completely after transmitting the information back,” said Pan, who was an associate professor in Bioengineering and recently moved to the University of Maryland.
In collaboration with the lab team of Chemistry Associate Professor Jefferson Chan, the nanoparticles have been tested in breast cancer cell lines, as well as in mice. In both cases, they had no adverse effects. Chan is also an affiliate in Biochemistry.
“We were excited to prove the complete degradability of these nanoparticles, which isn’t always possible with the currently reported nanoparticles,” Pan said.
The particles also emitted a signal, which was used to identify lymph nodes and confirm the degradation of the particles.
“The inherent optical properties of biliverdin allow us to use it without needing any additional, non-degradable chemicals,” Fathi said.
"Striking the perfect balance between diagnostic performance and biocompatibility is an immense challenge that this work has successfully achieved," Chan said.
The research team hopes to use these particles as vehicles for targeted cancer therapy as well as in other imaging technologies.