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A novel Ru(II) cyclometalated photosensitizer (PS), Ru-NH 2 , for photodynamic therapy (PDT) of formula [Ru(appy)(bphen) 2 ]PF 6 (where appy = 4-amino-2-phenylpyridine and bphen = bathophenanthroline) and its cetuximab (CTX) bioconjugates, Ru-Mal-CTX and Ru-BAA-CTX (where Mal = maleimide and BAA = benzoylacrylic acid) were synthesised and characterised. The photophysical properties of Ru-NH 2 revealed absorption maxima around 580 nm with an absorption up to 725 nm. The generation of singlet oxygen ( 1 O 2 ) upon light irradiation was confirmed with a 1 O 2 quantum yield of 0.19 in acetonitrile. Preliminary in vitro experiments revealed the Ru-NH 2 was nontoxic in the dark in CT-26 and SQ20B cell lines but showed outstanding phototoxicity when irradiated, reaching interesting phototoxicity indexes (PI) > 370 at 670 nm, and > 150 at 740 nm for CT-26 cells and > 50 with NIR light in SQ20B cells. The antibody CTX was successfully attached to the complexes in view of the selective delivery of the PS to cancer cells. Up to four ruthenium fragments were anchored to the antibody (Ab), as confirmed by MALDI-TOF mass spectrometry. Nonetheless, the bioconjugates were not as photoactive as the Ru-NH 2 complex.

Cyclohexane oxidation chemistry was investigated using a near-atmospheric pressure jet-stirred reactor at T = 570 K and equivalence ratio ϕ = 0.8. Numerous intermediates including hydroperoxides and highly oxygenated molecules were detected using synchrotron vacuum ultraviolet photoelectron photoion coincidence spectroscopy. Supported by high-level quantum calculations, the analysis of photoelectron spectra allowed the firm identification of molecular species formed during the oxidation of cyclohexane. Besides, this work validates recently published gas chromatography and synchrotron vacuum ultraviolet photoionization mass spectrometry data. Unambiguous detection of characteristic hydroperoxides (e.g., γ-ketohydroperoxides) and their respective decomposition products provides support for the conventional O2 addition channels up to the third addition and their relative contribution to the cyclohexane oxidation. The results were also compared with the predictions of a recently proposed new detailed kinetic model of cyclohexane oxidation. Most of the predictions are in line with the current experimental findings, highlighting the robustness of the kinetic model. However, the analysis of the recorded slow photoelectron spectra indicating the possible presence of C5 species in the kinetic model provides hints that the substituted cyclopentyl radicals from cyclohexyl ring opening might play a minor role in cyclohexane oxidation. Potentially important missing reactions are also discussed.