Polymeric coating improved piezoelectric properties of composites for drug delivery

Newswise — Scientists from Immanuel Kant Baltic Federal University found out that polymeric coating enables to improve the structure and properties of magnetoelectric composites, that are used in medicine for drug delivery and also in creation of implants and tissues. Thus, modification with polymer helps equal distribution of composite’s components, and also enhances its piezoelectric properties by 40%. That means that material accumulates electric charge after physical impact more quickly. Such ability can be used, for instance, for stimulation of growth and evolution of cells in tissues. Results of the research, supported by the grant of President program of Russian Scientific Fund (RNF), are published in Journal of Magnetism and Magnetic Materials.

Composites that have both magnetic and electric properties, are widely used in medicine, for instance, for drug delivery, for creation of tissues and implants. Besides, these compounds are used as catalysts in chemical industry. As an example of such composite, you can take a material on the base of magnetic nanoparticles from cobalt ferrite and polyvinylidene fluoride – fluorine containing polymer that have piezoelectric properties, in other words it is able to accumulate electric charge in response to physical impact. By this electric and magnetic characteristics of a composite are determined not only by properties of its components but their structure and mutual arrangement. However, there is still not enough information if coating of nanoparticles with additional materials, modifying their structure, can influence the structure and properties of composites.

Scientists from Immanuel Kant Baltic Federal University (Kaliningrad) studied, how modification of nanoparticles of cobalt ferrite with polymer polyethyleneglycol influences properties of the composite. To achieve this aim physics held nanoparticles in the solution of polyethyleneglycol during one hour, and then removed excessof polymer. Scientists dissolved modified nanoparticles with powder of polyvinylidene fluoride, poured the obtained solution in molds and dried till films appeared. Authors also analogously obtained composites, in which nanoparticles weren’t treated with polymer.

Study of materials’ structure shows that unmodified nanoparticles often aggregate, that means, stick together, as a result of it composite becomes discontinuous: in it appear areas with accumulation of particles and spaces without them. Modification with polyethyleneglycol helps equal distribution of nanoparticles in the matrix of polyvinylidene fluoride. Thus, the surface area of composites without particles reduced from 16% to 1 %, and the size of agglomerates from stuck together particles reduced by 39%.

Modified composites saved as magnetic and also piezoelectrical properties, that are characteristic for the base material. Moreover, treatment with polyethyleneglycol enhanced the ability to accumulate electric charge during physical impact of composite by 40% thanks to changes in its microstructure. Thus, modified composite reacted on physical impact more quickly. Elaborated materials potentially can be used in regenerative medicine. Thus, electrical impulses created by them in response to pressure can stimulate cell division in tissues and implants.

“In frames of further research, we plan to study mechanisms of interaction of polymer coating with components of magnetoelectric composites more profoundly. In future these materials can become a key element in creation of intellectual implants and bioelectrical systems, that are able to interact with living cells on the molecular level. Abilities of appliance of elaborated composites will open new horizons in regenerative medicine, and so enable creation of self-renewing artificial tissues. These researches pave the way to medicine of the future, where technology and biology are united for achievement of earlier unknown heights in treatment and recovery of human’s health”, – tells Vitalii Salnikov, research laboratory assistant, Research and Education Center “Smart Materials and Biomedical Applications” of Immanuel Kant Baltic Federal University.