biosensor (rus. биосенсор) — a device that detects chemical compounds using specific biochemical reactions.


A biosensor can use biochemical reactions mediated by isolated enzymes, immune complexes, tissues, organelles or whole cells, to detect chemical compounds, usually in the form of electrical, thermal or optical signals. Thus, biosensors are structures that enable the presence of certain molecules or biological structures to be identified and their quantity to be determined, in the test samples. For example, to detect a disease causative agent of botulism or scarlet fever in biological samples a biosensor can be set to detect small DNA fragments of these microorganisms using synthetic oligonucleotides 10-15 bases long (the probability of error in this case is one per billion). The gold nanosphere can be functionalisised by oligonucleotides. As a result of target DNA recognition the gold nanospheres will form clusters that lead to an increase in the local concentration and change their colour in solution (see Fig.).


A schematic representation of gold nanospheres (a, b) approaching the target DNA resulting
A schematic representation of gold nanospheres (a, b) approaching the target DNA resulting in the change of color due to the generation in the system of a colorimetric biosensor of gold nanosphere clusters [3].


  • Kurochkin Ilya N.
  • Shirinsky Vladimir P.
  • Maksimenko Alexander V.


  1. IUPAC. Compendium of Chemical Terminology. 2nd ed. (the «Gold Book») Compiled by A.D. Mc- Naught, A. Wilkinson. — Oxford: Blackwell Scientific Publications, 1997. XML on-line corrected version: , 2006. Created by M. Nic, J. Jirat, B. Kosata. Updates compiled by A. Jenkins. Last update, 07.09.2009.
  2. Anthony P. F. et al. Biosensors: fundamentals and applications/ Isao Karube, George S. Wilson — Oxford University Press, 1987. — 770 pp.
  3. Mark Ratner and Daniel Ratner, Nanotechnology: A Gentle Introduction to the Next Big Idea, Prentice Hall, Harlow, 2003.

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