Almost complete radiationless energy transfer from excited triplet state of a dim phosphor to a covalently linked adjacent fluorescent dye in purely organic tandem luminophores doped into PVA matrix

Abstract

Efficient harvesting of energy of the triplet exited state of dim organic phosphors by conjugated fluorophores is a general phenomenon that would be applicable for construction of novel photoluminescence-based sensors and organic light emitting devices.

Near‐Infrared Room‐Temperature Phosphorescence in Arylselanyl BODIPY‐Doped Materials

“…When excited at 350 nm, two types of energy transfer processes (FRET and TTET) between BP and HSeBOD may occur to give NIR RTP with a Φ p of 0.48 %. The efficiency ( E ) of the energy transfer was able to estimate to be 46.6 % according to the following equation; where τ DA and τ D are the lifetimes of the donor‐acceptor conjugate ( HSeBOD / BP ) and donor ( BP ), respectively [30] . Alternatively, 470 nm excitation led to NIR RTP behavior at Φ p =0.79 %; the process may contain the S 1 * state arising from the excimer with HSeBOD , which emits fluorescence at approximately 610 nm.…”

Wood‐Derived Carbon Materials and Light‐Emitting Materials

“…Since then, a number of studies investigating the fascinating properties of CDs have been carried out. [ 70–72 ] Compared with semiconductor quantum dots, [ 73,74 ] upconversion nanoparticles, [ 75,76 ] and organic dyes, [ 77,78 ] photoluminescent CDs prepared from wood‐derived biomass show many advantages, including sustainability, easy preparation, and favorable optical properties. [ 79 ] Additionally, compared to other biomass materials, wood‐derived polysaccharide was easy carbonized and fluorescent carbon dots can be easily prepared via low temperature hydrothermal carbonization method.…”

Photoactivity and optical applications of organic materials containing selenium and tellurium

“…The triplet can be transferred to another molecule either to begin a reaction cascade (oen to create singlet oxygen for photodynamic therapy) 43 or to amplify or delay a uorescent signal. 44 Substitution of the chalcogen with heavier analogues red-shis the absorption properties, 45 allowing deeper tissue penetration because lower energy light is less prone to absorption and scattering by biomolecules. 46 For example, thioguanine (3) produces singlet oxygen in 21% yield, which is useful in photodynamic therapy.…”

“…Energy from the triplet sensitizer upon excitation can be transferred to the uorescent dyes through Förster Resonance Energy Transfer (FRET), increasing the uorescence decay time and allowing it to persist at time scales beyond the nanosecond uorescence of biomolecules. 44,49 Without the presence of the dye, the sulfur and selenium-containing triplet sensitizers are quenched by oxygen, which occurs much faster than micro-second scale FRET to the uorescent dye. Once the sensitizer is bound to the pocket of the protein kinase, PIM, excited triplets are sterically protected from diffusional quenching by oxygen, allowing the triplet states to persist and undergo FRET to the uorescent dye (10) (Fig.…”

“…52 Moreover, while the sensitizer containing sulfur has a longer triplet decay time than the seleniumsubstituted analogue, the probes containing selenium are brighter because they undergo ISC more efficiently, leading to a higher triplet population. 53 The authors expanded their work to a different protein kinase, CK2, 54 and another uorescent dye, 44 using the same underlying method. In this series of studies, the authors have successfully utilized heavy-chalcogen substitution to maintain uorescence using FRET, while additionally inducing a time delay suitable for avoiding signal overlap with bioluminescence when detecting biological analytes.…”