Platinum trimethyl bipyridyl thiolates - new, tunable, red- to near IR emitting luminophores for bioimaging applicationsElectronic supplementary information (ESI) available: Synthesis and spectroscopic and crystallographic details of new materials, further details of DFT calculations, predicted absorption/emission spectra and orbitals involved. CCDC 1045315-1045320. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c5cc04003e

Synthetic, spectroscopic, computational and biological imaging studies of platinum trimethyl bipyridyl thiolate complexes of the general formula [PtMe 3 (bpy)SR] reveal these to be easily accessed, tunable bioimaging agents which feature an unusual σ-π* Inter-Ligand Charge Transfer (ILCT) transition, and in some cases emit into the Near infra-red (NIR). [PtMe 3 (S-C 6 H 4 -4-CO 2 Me)(bpy)] n + exemplifies a new class of luminophores, absorbing in the visible and emitting into the NIR, with good cell uptake making it suitable for fluorescence microscopy imaging.