What can I do with a nanosponge?

An interview with Professor Maurizio Prato

Neuronal network. Image by Credit Science Photo Library — Pasieka Brand X Pictures Getty Images

Nowadays, millions of people worldwide suffer from diseases of the central nervous system such as Parkison’s disease, spinal lesions, dementia. To recover or rehabilitate lost functions in neuronal tissues is undoubtedly one of the major challenges to modern medicine. Nanotechnology could provide an important contribution by developing a new generation of nanomaterials for neurological applications.

Maurizio Prato, full professor at the University of Trieste, explains us more about this fruitful collaboration between neurosciences and nanotechnology. For him, all started with the idea of a nanosponge.

Professor Maurizio Prato. Picture taken from https://dscf.units.it/en/news/10812

Professor Prato, what do you exactly mean by “nanosponge”?

With my research group, we’ve spent many years working with nanostructures, objects with characteristic sizes of the order of the billionth of a meter. In particular, we focused on carbon nanotubes, extremely thin filaments of carbon (more than 50 thousand times thinner than a human hair) with some extraordinary mechanical, chemical and electrical properties. We have recently managed to create a 3D mesh of interconnected and conductive pure carbon nanotubes, something that looks pretty much like a sponge.

A sponge (image by Olly Clarke); scanning electron microscopy image of a mesh of carbon nanotubes (L. Camilli et al. Nanotechnology 2014)

How did it occur to you that you could apply these structures in the field of the neurosciences?

We first thought of putting together neural tissues and carbon nanotubes more than 15 years ago, together with the research group of Professor Laura Ballerini from the International School of Advanced Studies in Trieste. The reason is easy to understand: neurons communicate with each other through electric signals and carbon nanotubes, renowned for their high electric conductivity, represented an excellent candidate to facilitate and support this type of communication. It’s an interesting example of interdisciplinary work, which merges nano- and neuro- sciences.

Which was the main aim of this work?

We wanted to test whether carbon nanosponges could restore the electric signal between the two parts of a lesioned spinal cord. At that time, it was already known that neurons in contact with carbon nanotubes show an increased communication capability. In addition, we had noticed that a carbon nanosponge did guide the formation of neural webs in vitro. Starting from those observations, we developed more and more sophisticated experiments, until we managed to use nanotubes-based 3D structures to dictate neurite web morphology toward successful reconnection of a lesioned spinal cord. Results have been published in Science Advances in July 2016 (link).

Sketch of 3D carbon nanotubes frame reconnecting two segregated spinal slices (S. Usmani et al. Science Advances 2016)

Are these “spongy” materials biocompatible?

These materials are prepared in the lab. They are totally artificial, so their biocompatibility needs to be tested. So far, though, we have observed that carbon nanosponges are perfectly compatible with the neural tissue. As shown by the research group of Professor Ballerini, when these sponges are implanted into the brain of a rat, they are invaded by neural fibers and they soon become a perfectly integrated structure within the brain.

Spinal slices cocultured in Control and in 3D carbon nanotube frame (3D CNF) after 14 days of growth (S. Usmani et al. Science Advances 2016).

Can we already foresee applications in humans?

Once demonstrated their biocompatibility, we think carbon nanosponges could be a valuable ally to repair lesions of spinal cord, but also to overcome the effects of other neurodegenerative diseases, which still remain without a valid cure.

Anna Lombardi

Professor Prato is a full Professor at the University of Trieste (Department of Chemical and Farmaceutical Sciences) since 2000 and member of the prestigious Accademia Nazionale dei Lincei since 2010.

This interview was part of the radio program RADAR, broadcast on Radio Rai Friuli Venezia Giulia on Tuesday 10th January 2017 (interviewer: Anna Lombardi).