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WELCOME TO THE PHOTONICS FOR LIFE GROUP IN NAPLES

The aim of this group is the application of ultrashort laser pulses (~ 100 fs) to several topics of interest in life sciences and material science. Our experimental equipment comprises a custom femtosecond laser system manifactured by Light Conversion Ltd (Pharos, delivering up to 1.5 mJ at 1030 nm with 2kHz rep rate, which pumps Harmonic Generator stage (HIRO) - with II (515 nm), III (343 nm), and IV (258 nm) harmonic outputs - and/or an Optical Parametric Amplifier (ORPHEUS) tunable from 0.2 μm to 3 μm. An additional Harmonic Generator is also available to produce harmonics of the oscillator output at 80 MHZ. Delay stages, spectrographs and CCD cameras allow us to perform time resolved fluorescence experiment on molecules of biological interest (e.g. 5-benzyl-uracil photocyclization). We are also setting up a transient absorption spectrometer to study the charge transfer in 2-dimensional material (graphene among the other).

The high average power delivered by our laser system is being exploited to achieve strong UV photon absorption in solution of living cells as well as antibodies. In the former case the absorption leads to DNA-protein and protein-protein cross-link, whereas in the latter system the UV absorption by the tryptophan residue gives rise to the disulfide bridge breaking thereby producing a reactive site that eventually allows an effective tethering of the antibody on gold surfaces.