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Palcewska et al. first demonstrated near infrared (NIR) visual response in human volunteers upon two-photon absorption (TPA), in a seminal work of 2014, and assessed the process in terms of wavelength- and power-dependence on murine \textit{ex-vivo} retinas. In the present study, ex-vivo electroretinography (ERG) is further developed to perform a complete characterization of the effect of NIR pulse duration, energy, and focal spot size on the response. The same set of measurements is successively tested on living mice. We discuss how the nonlinear intensity dependence of the photon absorption process is transferred to the amplitude of the visual response acquired by ERG. Finally, we show that the manipulation of the spectral phase of NIR pulses can be translated to predictable change in the two-photon induced response under physiological excitation conditions.

The activity of the GAP-Biophotonics research group at the University of Geneva in the field of coherent control for discriminating similar biomolecules, such as flavins, proteins and DNA bases, is presented and future developments are discussed.

A straightforward high-yield synthesis for the photoinitiator bis(2,4,6-trimethylbenzoyl)phenylphosphane oxide (16, IRGACURE 819) involves: i) the reaction of phenyldichlorophosphane, PhPCl2, with sodium to give [Na2(P2Ph2)(tmeda)]6 (5); ii) protonation of 5 with tert-butanol to give 1,2-diphenyldiphosphane, PhHP-PHPh (12); iii) reduction of 12 by sodium to yield [Na(PHPh)]x (13); iv) protonation of 13 with tert-butanol to give phenylphosphane PhPH2 (14) in excellent yields; v) reaction of 14 with 2,4,6-trimethylbenzoylchloride (MesCOCl) in presence of the NaOt-Bu formed in steps ii and iv to give bis(2,4,6-trimethylbenzoyl)phenylphosphane 7; vi) oxygenation of 7 with 30% aqueous hydrogen peroxide to give the final product 16. This reaction can be performed in toluene with about 4 vol-% of tmeda as an activator in a one-pot synthesis without changing the solvent. The structures determined by X-ray diffraction of the unique hexameric aggregate 5 and 16 are reported.

Although radiation curing is an established technology used in many industrial manufacturing processes, new applications and technical challenges stimulate the development of tailor-made photolatent catalysts. The development of a new bisacylphosphine oxide (BAPO) photoinitiator enables the efficient curing of coatings stabilized with a light stabilizer package consisting of a UV-absorber and a hindered amine light stabilizer (weather-resistant coatings for outdoor applications). Tailor-made photolatent catalysts represent a key feature in the development of new electronic applications like laser direct imaging for the production of printed circuit boards, color filters for liquid crystal displays used in computer flat screens and chemically amplified photoresists for microelectronics.

Organic corrosion inhibitors, which are used as additives in paints and lubricants to provide permanent corrosion protection, are briefly discussed.