IISiS and Clemson University: Biocompatible Gold Nanoparticle Technology

Main article: Nanoparticles in Medicine

2020: Found a method for producing biocompatible gold nanoparticles

May 26, 2020 Internet- the publication Zdrav.Expert learned that an international group of researchers NITU "MISiS" and (Clemson University Clemson University, Clemson,) USA proposed their own method for producing nanoparticles gold, based on UV synthesis. Method excludes use of aggressive chemical agents, obtained nanoparticles are safe for organism and can be used for diagnosis and therapy oncological of diseases. The results are published in the international journal scientific Biomaterials Science.

According to official figures, as of May 2020, cancer remains one of the most common causes of death in the world. Therefore, researchers do not stop looking for ways to diagnose and treat cancer, including using nanotechnology.

Gold nanoparticles are used in the catalysis process, in electronics, solar cells, but they are of greatest interest in terms of biomedicine. Their important advantage is a combination of the properties necessary for so-called bioimaging, that is, detailed diagnosis of the tumor and subsequent therapy.

As agents for bioimaging, gold nanoparticles are usually used in computed tomography. Tumor therapy using gold nanoparticles can be carried out through the so-called photothermal therapy, when particles first accumulate in the tumor, and then warm up under the influence of an external field and destroy cancer cells.

At the same time, existing methods for producing gold nanoparticles usually require the use of sufficiently aggressive chemical agents, which makes their further use in biomedicine difficult, or require several stages of synthesis, which increases the cost of production.

In their work, scientists at NITU MISiS and Clemson University propose an "environmentally friendly" method for producing gold nanoparticles, in which the gold salt is HAuCl4 mixed with a copolymer in the composition: polylactic acid-polyethylene glycol in the presence of polyvinyl alcohol and a special photoinitiator Irgacure. This technology excludes the use of aggressive substances and chemical agents that are toxic to the living body.

{{quote 'author
= explained Roman Akasov, one of the co-authors of the work, researcher at the laboratory "Biomedical nanomaterials" NITU "MISiS," PhD|Despite the long list of components, all of them biocompatible and as of May 2020 are actively used in biomedicine. The resulting mixture is mixed by ultrasound to form a double water-oil-water emulsion. Further, it can be irradiated with ultraviolet light, as a result of which gold nanoparticles are formed in the solution. The particles are surrounded by a polymer which gives them biocompatibility and stability properties in aqueous solutions. The emulsion is converted from whitish-transparent to red, which is an indicator of the correct photopolymerization. The particle size in our experiments was about 100 nanometers, which is good for biomedical applications, and the particles were not toxic to cells.}}

Also in the work, the authors managed to show that gold nanoparticles accumulate in the cytoplasm of cells - both tumor glioma and immune cells macrophages. This opens up the possibility of individual diagnosis and therapy of tumor diseases. In the future, it is planned to modify the surface of nanoparticles with special molecules in order to specifically find a tumor in the body. However, researchers offer another option for using their method - as a bioconstructor.

The resulting emulsions can be introduced into the cell or even the body even before the photopolymerization stage - the process of synthesis of polymers under the influence of light - and synthesized into gold nanoparticles directly in the tissue under study. At the same time, the properties of the obtained nanoparticles can be judged by the features of the living environment in which they are located, which can be an important tool for studying the biology of the cell and the processes that occur in it.

As of May 2020, the group continues a series of laboratory experiments as part of the preclinical stage of research.