MEMS interferometric image

Coherent control of biological molecules and biomedical applications

The optical identification and discrimination of molecules that exhibit nearly identical absorption and fluorescence spectra is usually considered as fully elusive. However, the advent of lasers that allow time resolutions shorter than molecular motion provides new tools to reach this goal. By addressing the molecular dynamics in ‘real time’ and by making use of molecular quantum interference, quantum control has already exhibited its unique capability to selectively break or excite specific molecular bonds.

We recently demonstrated that quantum control is able to discriminate between several pairs of nearly identical biomolecules that display almost identical absorption and fluorescence spectra The method, called Optimal Dynamic Discrimination (ODD) is, moreover, highly sensitive, as it can use molecular fluorescence as a detection channel. ODD opens new perspectives for many laser applications, such as label-free fluorescence microscopy, protein identification and specific detection of hazardous molecules and pathogens, also from a remote distance.

A substantial technology development accompanies this project. In order to dispose of an efficient and versatile device for shaping femtosecond pulses in the deep UV, we have realized a MEMS based all-reflective pulse shaper in collaboration with CSEM in Neuchâtel.

Further reading

Quantum Control of Tightly Competitive Product Channels, M. Roth, L. Guyon, J. Roslund, V. Boutou, F. Courvoisier, J.-P. Wolf, and H. Rabitz Phys. Rev. Lett. 102, 253001 (2009) [DOI: 10.1103/PhysRevLett.102.253001]
How shaped light discriminates nearly identical biochromophores, J. Petersen, R. Mitric, V. Bonacic-Koutecky, J.-P. Wolf, J. Roslund, H. Rabitz, Phys. Rev. Lett. 105, 073003 (2010) [DOI: doi:10.1103/PhysRevLett.105.073003]
Discriminability of tryptophan containing dipeptides using quantum control, S. Afonina, O. Nenadl, A. Rondi, L. Bonacina, J. Extermann, D. Kiselev, I. Dolamic, T. Burgi and J. P. Wolf, Appl. Phys. B, 111, (4) 541-549 (2013) [DOI: 10.1007/s00340-013-5370-0]
Coherent manipulation of free amino acids fluorescence, A. Rondi, L. Bonacina, A. Trisorio, C. Hauri and J.-P. Wolf, Phys. Chem. Chem. Phys., 14, 9317-9322 (2012) [DOI: 10.1039/C2CP23357F]
Design, Simulation, Fabrication, Packaging, and Characterization of MEMS Micromirror Array for Femtosecond Pulse- Shaping in Phase and Amplitude, S. Weber, L. Bonacina, W. Noell, D. Kiselev, J. Extermann, F. Jutzi, S. Lani, O. Nenadl, J.-P. Wolf, and N. de Rooij, Review of scientific instruments, 82, 075106 (2011) [DOI: 10.1063/1.3606440]