A Unique Material for Surgery and Implantology Created in Russia

10:09, November 24, 2021

It combines biocompatibility, biodegradability and piezoelectric properties

Scientists from Ural Federal University together with their foreign colleagues and researchers from Tomsk Polytechnic University have created a new material that can be widely used in surgery, RIA Novosti reports. According to the authors, structures made of this material can be used in bone tissue engineering (implantology), for cartilage repair, creation of wound dressings and suture threads. The study was published in the journal Nano Energy.

Electrical stimulation is known to accelerate the repair of bone defects, such as fractures or cracks. Therefore, scientists are now attracting the attention of piezoelectric materials capable of converting mechanical energy into electrical energy and vice versa.

In addition, the treatment of certain diseases requires biodegradable implants that dissolve in the body over time and do not require repeated surgical intervention for their removal, thus reducing the risks of inflammation. These implants must also have an ordered three-dimensional structure and certain mechanical properties in order to restore the damaged bone area.

Thus, modern regenerative medicine, in particular bone implantology, needs to develop new smart piezoelectric materials that can both biodegrade and provide electrical/mechanical stimulation to cells and body tissues. The solution of this complex problem requires an interdisciplinary approach.

UrFU scientists, together with colleagues from Tomsk Polytechnic Institute and scientists from Belgium, Germany, and Portugal, have developed biodegradable three-dimensional structures, scaffolds, based on poly-3-oxybiturate polymer fibers with an increased piezoelectric response (up to 2.5 times) and surface charge (up to 9.5 times).Researchers for the first time studied in detail the structural and molecular changes in the polymer composite caused by the addition of a nanoscale agent based on graphene oxide. In addition, they were the first in the world to demonstrate the piezo response of poly-3-oxybutyrate itself at the nanoscale.

A long-known biocompatible and biodegradable synthetic polymer, poly-3-oxybutyrate (POB), was used to solve the problem. This polymer has piezoelectric properties that are close to those of bone collagen, although inferior to non-biodegradable analogs.

To improve the piezoelectric properties of FOB, scientists decided to use biocompatible nanoscale reduced graphene oxide (VOG). Its chemical characteristics and high specific surface area make it suitable for drug delivery. Using FOB and VOG, the authors of the study developed new biodegradable three-dimensional polymeric scaffolds with enhanced piezoelectric response and potential (charge) on the surface.

There are very few such materials that would combine biocompatibility, biodegradability, piezoelectric properties and the possibility of obtaining a three-dimensional structure with specified mechanical properties. That is why the new development can find wide application in medicine, said Andrey Kholkin, head of the Laboratory of Nanoscale Segnelectric Materials at UrFU. The work was partially supported by a mega-grant (project No. 075-15-2021-588) within the framework of cooperation between UrFU and TPU.

"To obtain our scaffolds, we used the electroforming method, which is notable for its simplicity and unique ability to control the size of polymer fibers at the nanoscale. To conduct a detailed study of the structure and properties of the developed scaffolds, we used a range of high-precision analytical methods: from scanning microscopy, X-ray photoelectron spectroscopy to piezoelectric force microscopy, in which our laboratory is a world leader," said Andrey Kholkin.

Today, the developed scaffolds are undergoing biological research, which, upon successful completion, will require a full range of preclinical tests. The authors hope for their wide application in medical practice in the near future.