Smart transformable nanoparticles promise breakthroughs in tumor diagnosis and treatment

For more than three decades, biomedical nanomaterials have been successfully developed for the benefit of theranostics, a compound term referring to the diagnosis and treatment of tumors. The nanoparticles must reach the tumor site and its distinct microenvironment to target tumor treatment.

Recent studies show that the physical properties of nanoparticles, in particular their size and shape, significantly influence their biological behaviors. Monitoring of these material properties is necessary to ensure that the treatment is released at the tumor level, after the particles have circulated through various other healthy physiological microenvironments.

In Applied physics exams, researchers from China and the United States are examining how biology triggers morphological changes in certain types of nanoparticles. These types of particles are called smart transformable nanoparticles because they can change their size and shape upon stimulation of their surrounding environment.

These intelligent transformable nanoparticles are particularly promising for tumor theranostics because their physical properties will adapt to physiology. These adaptations improve particle circulation, biodistribution, tumor penetration, tumor retention, and subcellular distribution for targeted therapy.

“Intelligent transformable nanoparticles can change their morphology under different physiological conditions according to therapeutic requirements,” said co-author Jianxun Ding. “In our study, we reveal the structural designs of these intelligent systems as well as the underlying mechanisms of the transformations.”

The researchers present the designs of transformable nanoparticles as a guideline for their construction and discuss biomedical applications in the field of theranostics. Ding and his colleagues present their point of view through new classifications for the design of nanoparticle transformation and the mechanisms contributing to change.

For example, researchers divide design transformation into two broad categories: size and shape. For nanoparticles with transformable size, the alterations are then divided into small to large and large to small transformations. The study reveals detailed and rational designs of transformable nanoparticles according to their structures.

Regarding the mechanisms contributing to the transformation of nanoparticles, “we believe that both the structure and the stimuli made a great contribution,” said Ding. “For example, different pH values ​​decided on the precise site of transformation, which correlates with various physiological, extracellular and endo / lysosomal conditions.”

Nanoparticles with constant physical morphologies have been widely studied and applied in tumor theranostics in the past, while more recent studies of nanoparticle transformation phenomena have mainly focused on response to stimuli. So far, however, there has not been an in-depth discussion of the designs and applications of morphologically transformable nanoparticles.

“Our review covers the structural design, transformation mechanism, and biomedical application of intelligent transformable nanoparticles, and also includes perspectives on their limitations,” Ding said. “We believe this review will shed light on this important area.”