Delivering drugs directly to cells using nanoparticles

Professor Michael Yu’s research team, with support from ANFF-Q, have developed a novel method for preparing nanoparticles to improve biomolecule loading capacity and cell delivery.

Confocal microscopy images of HCT-116 cells treated with free Cy3-OligoDNA (100 nM) (first row) and the complex of invaginated MHCS (15 μg mL−1) and Cy3-OligoDNA (100 nM) (second row). The cytoskeletons and nuclei were stained by Alexa Fluor 488 phalloidin (green) and DAPI (blue), respectively.

Delivering drugs directly into target cells offers exciting possibilities for the treatment of disease. Professor Michael Yu’s research team from the Australian Institute for Bioengineering and Nanotechnology , based at The University of Queensland, has developed hollow, mesoporous carbon nanoparticles that can successfully deliver large biomolecules into cells, making them promising nanocarriers for medical applications.

The researchers developed a novel method for preparing the nanoparticles through a facile and surfactant-free approach. Using this process, the researchers were able to control the particle size, pore size and structure of the nanoparticles. As the particles were too small to be observed with a conventional optical microscope, a confocal microscope at the ANFF-Q node was used for observations with technical support provided by ANFF-Q Professional Officer Dr Elena Taran .

The particles were loaded with Oligo DNA molecules, labelled with a cyanine dye and incubated with target cells, after which cellular uptake was evaluated. By studying the performance of nanoparticles with different shapes and sizes, the team was able to confirm for the first time that those with an invaginated structure (whereby one side of the sphere is shrunken inwards) show a better compatibility with blood than those with intact structures.

It was also found that pristine hollow carbon nanoparticles with large pore size and high volume demonstrate a high biomolecule loading capacity and are able to successfully deliver biomolecules into cells. The high uptake means fewer carbon nanoparticles are required for drug delivery in practical scenarios.

The results of this project were published in the scientific journal Chemistry of Materials*. Future work will involve loading the nanoparticles with anti-cancer medication so that the therapeutic effect of delivery can be evaluated. This research has paved the way for the mass production of carbon nanoparticles with optimum drug delivery capabilities.

*Zhang, H. et al. (2015). Self-Organized Mesostructured Hollow Carbon Nanoparticles via a Surfactant-Free Sequential Heterogeneous Nucleation Pathway. Chemistry of Materials, 27, 6297-6304, doi:10.1021/acs.chemmater.5b01993.