Giant Step For NanoMaterial Manufacturing

Tiny fibrils extracted from plants have been getting a lot of attention for their strength. These nanomaterials have shown great promise in outperforming plastics, and even replacing them. A team led by Aalto University (Finland) has now shown another remarkable property of nanocelluloses: their strong binding properties to form new materials with any particle.

Cohesion, the ability to keep things together, from the scale of nanoparticles to building sites is inherent to these nanofibrils, which can act as mortar to a nearly infinite type of particles as described in the study. The ability of nanocelluloses to bring together particles into cohesive materials is at the root of the study that links decades of research into nanoscience towards manufacturing.

In a paper just published in Science Advances, the authors demonstrate how nanocellulose can organize itself in a multitude of different ways by assembling around particles to form highly robust materials.

Nanocellulose can also form structures known from pulp technology with the particles

This means that nanocelluloses induce high cohesion in particulate materials in a constant and controlled manner for all particles types. Because of such strong binding properties, such materials can now be built with predictable properties and therefore easily engineered’, explained  the main author, Dr Bruno Mattos, The moment anytime a material is created from particles, one has to first come up with a way to generate cohesion, which has been very particle dependent, ‘Using nanocellulose, we can overcome any particle dependency’, Mattos adds.

The universal potential of using nanocellulose as a binding component rises from their ability to form networks at the nanoscale, that adapt according to the given particles. Nanocelluloses bind micrometric particles, forming sheet-like structures, much like the paper-mâché as done in schools. Nanocellulose can also form tiny fishnets to entrap smaller particles, such as nanoparticles. Using nanocellulose, materials built from particles can be formed into any shape using an extremely easy and spontaneous process that only needs water. Importantly, the study describes how these nanofibers form network following precise scaling laws that facilitates their implementation. This development is especially timely in the era of the nanotechnologies, where combining nanoparticles in larger structures is essential. As Dr Blaise Tardy points out, ‘New property limits and new functionalities are regularly showcased at the nanoscale, but implementation in the real world is rare. Unraveling the physics associated with the scaling of the cohesion of nanofibers is therefore a very exciting first step towards connecting laboratory findings with current manufacturing practices’. For any success, strong binding among the particles is needed, an opportunity herein offered by nanocellulose.


DNA Folds Into A Smart Nanocapsule For Drug Delivery

Researchers from University of Jyväskylä and Aalto University in Finland have developed a customized DNA nanostructure that can perform a predefined task in human body-like conditions. To do so, the team built a capsule-like carrier that opens and closes according to the pH level of the surrounding solution. The nanocapsule can be loaded—or packed—with a variety of cargo, closed for delivery and opened again through a subtle pH increase.

DNA folds into a smart nanocapsule for drug delivery
The pH-responsive DNA origami nanocapsule (blue) loaded with an enzyme (yellow color, high pH). 

The function of the DNA nanocapsule is based on pH-responsive DNA residues.To make this happen, the team designed a capsule-like DNA origami structure functionalized with pH-responsive DNA strands. Such dynamic DNA nanodesigns are often controlled by the simple hydrogen-bonding of two complementary DNA sequences. Here, one half of the capsule was equipped with specific double-stranded DNA domains that could further form a DNA triple helix — in other words a helical structure comprised of three, not just two DNA molecules — by attaching to a suitable single-stranded DNA in the other half.