Key Points

• Monash researchers have developed a method to prepare elongated nanocrystals to deliver therapeutic drugs

• Elongated nanocrystals can carry a high payload of drugs to potentially increase drug targetability and also decrease dosage frequency and side effects

• The researchers used a combination of deuteration, X-ray and neutron techniques at ANSTO to distinguish the three layers of the nanocrystal

Monash University researchers have used advanced techniques at ANSTO to investigate the production of new, elongated polymer nanocapsules with a high payload of drug nanocrystals to potentially increase drug targetability, and also decrease dosage frequency and side effects.

This method had not been investigated previously and represents a pioneering method of investigation in the field of colloidal science applications for drug delivery.

Nanoparticles have been used to increase the delivery efficiency of cancer therapy because of their biocompatibility, versatility and the easiness of functionalisation.

The team engineered novel elongated polymer nanocapsules, which are unlike the more well-known spherical nanocapsules.

The elongated polymer nanocapsules were made with elongated liposomes or surfactant vesicles and used drug nanocrystals as a template. 

The results provided strong evidence that the elongated structure could be retained, and also confirmed that the loading method to form rod-like drug nanocrystals inside liposomes was a practical solution.

The combination of the high drug payload, in the form of encapsulated nanocrystals, and the non-spherical feature of liposomes represented a more efficient delivery system.

Spherical hollow nanocapsules have been studied extensively, but the formation of elongated nanocapsules containing active pharmaceuticals as therapeutic agents has been previously largely unsuccessful. 

“There are difficulties in retaining the elongated shape and their encapsulation efficiency is low,” explained researcher Yunxin (Cindy) Xiao, a PhD candidate working in the Nonlaminar group with Prof Ben Boyd at the Monash Biomedicine Discovery Institute. and the recipient of the Australian Institute of Nuclear Science and Engineering Post Graduate Research Award.

“The elongated shape is better because it is more difficult for immune cells to  internalise them and because their therapeutic efficiency at the target site can be maximised.”

After obtaining promising structural results using a liposomal template investigated using the small angle X-ray scattering beamline at ANSTO’s Australian Synchrotron and the small and ultra-small small-angle neutron scattering instruments Bilby and Kookaburra in previous research, the template was used to form elongated polymer nanocapsules.

The researchers used vesicles made of surfactants as templates, which allowed for the polymerisation of a less permeable shell inside these….