At the University of Alabama at Birmingham, scientists have developed a new microparticle that carries doxorubicin chemo load, that can be imaged within the body and then made to release the cargo using external ultrasound.
The polymer particles consist of layers of tannic acid and poly(N-vinylpyrrolidone), or TA/PVPON, both fairly biocompatible substances. They are generated over a solid core that is dissolved once the exterior shells are ready. By adjusting the relative quantities of the two compounds and trying different numbers of layers in the shell, the team was able to achieve high ultrasound contrast while keeping the drug in place. There’s a lot of variations left to play with, and different applications may require different formulations of these microparticles.
“We envision an entirely different approach to treating solid human tumors of numerous pathologic subtypes, including common metastatic malignancies such as breast, melanoma, colon, prostate and lung, utilizing these capsules as a delivery platform,” said Eugenia Kharlampieva, Ph.D., an associate professor in the Department of Chemistry, UAB College of Arts and Sciences, in a statement. “These capsules can protect encapsulated therapeutics from degradation or clearance prior to reaching the target and have ultrasound contrast as a means of visualizing the drug release. They can release their encapsulated drug cargo in specific locations via externally applied ultrasound exposure.”