Tunable Fluorescent/Phosphorescent Platinum(II) Porphyrin–Fluorene Copolymers for Ratiometric Dual Emissive Oxygen Sensing

Abstract

A series of new platinum(II) 5,15-bis(pentafluorophenyl)-10,20-bis(phenyl)porphyrin-9,9-dioctylfluorene copolymers, in which the relative intensities of the blue fluorescence and red phosphorescence can be easily tuned by the initial feed ratio of the two monomers or energy transfer between the fluorescent and phosphorescent units, have been designed and prepared for the application in ratiometric dual emissive oxygen sensing. To the best of our knowledge, this is the first example of a ratiometric oxygen sensor based on dual fluorescent/phosphorescent polymers or copolymers containing transition-metal complexes. It also provides an alternative and easy way to achieve dual emissive oxygen sensing.

Multifunctional Phosphorescent Conjugated Polymer Dots for Hypoxia Imaging and Photodynamic Therapy of Cancer Cells

“…Pt(II) porphyrin complexes have been demonstrated to be excellent O 2 probes and photosensitizers for PDT 12. However, their low biocompatibility and poor water‐solubility influence the practical biomedical applications.…”

“…Optical imaging techniques also play important roles in the icO 2 detection. Among a variety of emissive dyes available for icO 2 detection,10 phosphorescent transition‐metal complexes (PTMCs)11, 12 have unique advantages, owing to the efficient reversible quenching of phosphorescence by the triplet ground state of O 2 . In addition, PTMCs exhibit large Stokes shift, high photostability, and long emission lifetime, which are beneficial for biosensing and bioimaging.…”

“…Over the recent decade, many PTMCs‐based icO 2 probes and PDT photosensitizers have been reported 11, 12, 15. However, many of the reported probes and photosensitizers are hydrophobic small molecules, which suffer from poor water‐solubility, high cytotoxicity, and low molar absorption coefficient in the visible region.…”

Deep-red electrophosphorescence from a platinum(II)–porphyrin complex copolymerised with polyfluorene for efficient energy transfer and triplet harvesting

“…Still few investigations have been reported for the incorporation of Pt(II)-porphyrin directly in the polymer backbone. [16][17][18] Of the few previously reported polymers, porphyrins are generally incorporated by the β-pyyrollic position. [16,18] Meso incorporation into a polyfluorene polymer has previously been achieved by Xiang but was studied only in the context of oxygen sensing and was synthesised via a less controlled (compared to Suzuki) Yamamoto reaction.…”

“…[16,18] Meso incorporation into a polyfluorene polymer has previously been achieved by Xiang but was studied only in the context of oxygen sensing and was synthesised via a less controlled (compared to Suzuki) Yamamoto reaction. [17] Here, we investigate the inclusion of Pt(II)-porphyrin, a dimesityl diphenyl porphyrin platinum (MPP-Pt) in a polyfluorene host polymer, poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PFO) where the phosphorescent dopant is covalently linked to the fluorescent host via phenyl groups (PF-MPP(Pt)). We also characterised the steady-state and time-resolved photoluminescence (PL) of the materials, which were then incorporated in light-emitting diodes.…”