TSU is developing a methodology to monitor the quality of biosensors

5 February 2018

Anastasia Shabalina, a research assistant at the SPhTI (Siberian Physical and Technical Institute) won a grant from the President of the Russian Federation for the development of methods for assessing the quality of the surface of aptasensors. Aptasensors are a new class of detectors based on aptamers - single-stranded DNA and RNA molecules. Such biosensors open up new possibilities in the early diagnosis of diseases; for example, they are used to detect tumor markers in a person’s blood and plasma.

- The aptasensors have an abnormally high sensitivity and extremely low detection limits for target objects, - says Anastasia Shabalina, a researcher at the SPhTI’s Laboratory of New Materials and Advanced Technologies. – Proteins, viruses, and cells of affected tissues are the target for aptasensors. Today, researchers are deciphering the structure of the protein and, based on the data obtained, creating biological detectors for the early detection of various pathologies, for example, tissue necrosis, the appearance of tumors, and increased vascular endothelial growth.

The main functional indicator of aptasensors is the response to a given target. This characteristic directly depends on how the surface of the biosensor is qualitatively modified by signal molecules - aptamers, from the continuity of the modifying layer, and its thickness and the mutual arrangement of the molecules in it. This scientific direction is quite new, so there is no universal methodology for laboratory evaluation of the structure of the surface layer. However, the development of such an approach is necessary to exclude the possibility of gross errors in the analysis, especially in the analysis of tumor markers.

TSU scientists’ research in this area began after meeting with specialists from the Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky. Based on it, six new aptamers for aptasensors were developed. To assess the quality of the signal and the modified surface of the bio-detectors, the employees of the State Medical University turned to the materials scientists of SPhTI, who have experience in creating electrochemical sensors modified with nanoparticles.

- The objects of research proposed by the specialists of the Krasnoyarsk State Medical University interested us, and we began interaction, which will continue in the project supported by the grant of the President of the Russian Federation,- says Anastasia Shabalina. - The research is aimed at achieving two goals. The first is to create an approach that will allow evaluating the structure and properties of the aptameric layer. The second is the testing of the technique developed with reference to the real sample - the aptasensor - for the detection of cancer markers of lung cancer in the blood plasma. The samples of materials will be provided by our Krasnoyarsk partners.

In the long term, the recommendations developed by the SPhTI scientist can be used not only to control the quality of biosensors but also to solve a wide range of research and practical problems: in particular, to use the developed recommendations for studying other organic layers on solid substrates and to apply the approach at production sites while scaling and launching new products into production.