LNBE came out with nonlinear optical cell with uniquely high efficiency of IR radiation conversion

The prestigious international journal Biosensors and Bioelectronics has published a study on Remarkably enhanced photoelectrical efficiency of bacteriorhodopsin in quantum dot–purple membrane complexes under two-photon excitation by three researchers at the Laboratory of Nano-Bioengineering (LNBE) of NRNU MEPhI: Victor Krivenkov, Ph.D., research assistant, Pavel Samokhvalov, Ph.D., leader of the Nanochemistry Group of LNBE, and Prof. Igor Nabiev, Ph.D., D.Sc., leading scientist of LNBE (Biosensors and Bioelectronics, 2019, 137, 117–122).

The paper describes a photoelectrochemical cell based on a nano–bio hybrid material consisting of the so-called purple photosensitive membranes of the Halobacterium salinarum bacterium and quantum dots which efficiently operates in the two-photon excitation mode in the infrared (IR) spectral region. The H. salinarum purple membranes contain the photosensitive protein bacteriorhodopsin, which is the agent generating the transmembrane electrical potential. The protein's own light absorption spectrum is rather narrow, not covering the IR region. The photoelectrochemical cell performance is enhanced because the quantum dots, whose unique nonlinear optical properties make it possible to convert two absorbed IR photons into one quantum with a higher energy, transfer the excitation energy to bacteriorhodopsin via a nonradiative route, Förster resonance energy transfer (FRET).


The photoelectrochemical cell developed in LNBE is unique among similar cells based on natural proteins and upconversion nanoparticles in that the authors have succeeded in obtaining a two-photon photoresponse owing to excitation of quantum dots in the IR spectral region, as well as highly efficient transfer of the energy of their excitation to bacteriorhodopsin. As a result, the new nano–bio hybrid system converts IR light into electricity 4.3-fold more efficiently than the original purple membranes. This has become possible due to the unique next-generation quantum dots with a multilayer shell also synthesized in LNBE. These quantum dots have a photoluminescence quantum yield as high as 100% and can be tightly bound to the purple membrane surface.

Owing to the highly efficient energy conversion, nonlinear nature of the two-photon excitation, and the related sharp threshold of radiation sensitivity, the novel photoelectrochemical cell could be widely used in biosensing, designing of elements for optical and holographic computing, and various fields of opto- and bioelectronics.

The Biosensors and Bioelectronics, with an impact factor higher than 8, is among the world's leading journals, included in Q1 of the SCImago ranking in six subject categories (https://www.scimagojr.com/journalsearch.php?q=15437&tip=sid):

- Biomedical Engineering,

- Biophysics,

- Biotechnology,

- Electrochemistry,

- Medicine, and

- Nanoscience and Nanotechnology.


Victor A. Krivenkov, Ph.D., research assistant (vkrivenkov@list.ru)

Maria G. Korenkova, director of external relations (MGKorenkova@mephi.ru)

Laboratory of Nano-Bioengineering, Moscow Engineering Physics Institute
31 Kashirskoe shosse, 115409 Moscow, Russian Federation

© 2012 Laboratory of Nano-BioEngineering