Protein on a carbon nanotube has become both a molecular searchlight and a memory element

Russian scientists together with foreign colleagues have developed a full-fledged bioelectronic photocell based on just one molecule of a luminous protein connected to a carbon nanotube. According to the Russian Science Foundation such a system is capable of storing information.

“Our development will make it possible to create powerful and compact devices controlled by light for storing and transmitting information. In addition, both components of our cells are biodegradable and ecofriendly, so they can become the basis of environmentally friendly solar panels," said Ivan Bobrinetsky, a leading researcher at the Research and Educational Center "Probe Microscopy and Nanotechnologies" of MIET.

Optoelectronic devices that are capable of storing and transmitting information, perceiving light of various wavelengths, form the basis of lasers, LEDs and some memory devices. Among them there are systems containing, in addition to electronic elements, biomolecules, such as proteins. Such hybrid systems are cheaper, more ecofriendly and at the same time retain the necessary optical properties.

During this research, scientists from MIET, the P.N. Lebedev Physical Institute, Skolkovo Institute of Science and Technology together with colleagues from Cardiff University (Great Britain), Aalto University (Finland) and the University of Novi Sad (Serbia) modified carbon nanotubes with green fluorescent protein (GFP). Phenylazide molecules served as a “bridge” between them.
GFP is a "barrel" of a folded amino acid chain, with a fluorophore molecule inside. The fluorophore molecule under the action of radiation acquires additional energy, undergoes electronic rearrangements, and then returns to its original state, giving off excess energy in the form of its own radiation. Another option is also possible - heat release, but the “barrel” protects it from this, ensuring long-term preservation of fluorescent properties.

The researchers studied the structure of the obtained compounds and found out that it was possible to control the type of the formed optoelectronic element due to the protein. This system can exchange with the external environment not only energy, but also charge carriers.

The results of the research are published in the Advanced Functional Materials journal.