Organic Host‐Guest Materials with Bright Red Room‐Temperature Phosphorescence for Persistent Bioimaging^†

Abstract

Comprehensive Summary Organic room‐temperature phosphorescence (RTP) materials have attracted immense attention in bioimaging due to their long emission lifetime and large Stokes shift. RTP materials with long emission wavelength can improve the penetration depth for bioimaging. However, the design of red persistent RTP materials is still challenging. In this study, a fused‐ring structure has been proposed to effectively decrease the triplet energy level, thus extending the emission wavelength of phosphorescence. In addition, the fused‐ring structure exhibits a high molar extinction coefficient (ɛ) and high luminescence efficiency due to the rigid structure. A new class of crystalline hosts (iminodibenzyl, IDB) are developed to stabilize the triplet excitons that are generated from the fused‐ring molecules. The maximum RTP wavelength of doping materials can reach 635 nm with a lifetime of 9.35 ms. Water‐disperse nanoparticles are successfully prepared for in vivo time‐resolved bioimaging, which eliminates the background fluorescence interference from biological tissues. These reveal a delicate design strategy for the construction of long‐wavelength emissive RTP materials for high‐resolution bioimaging.

Supramolecular Surface Engineering of Carbon Dots Enables Matrix‐Free Room Temperature Phosphorescence†

“…[ 12‐19 ] Despite the well documented fluorescent properties, CDs with RTP have also been reported by several groups. [ 20 ] Lin and co‐workers reported the production of effective RTP by aggregation‐induced of CDs in trimellitic acid. [ 21 ] Shan and co‐workers achieved UV phosphorescence by restriction of CDs in NaCNO crystals.…”

Ultralong Organic Phosphorescence of Triazatruxene Derivatives for Dynamic Data Encryption and Anti‐counterfeiting

“…All organic room temperature phosphorescence (RTP) luminogens have drawn extensive attentions and shown intelligent potentials in the field of optoelectronic devices, [ 1‐3 ] sensor, [ 4‐5 ] information storage, [ 6‐10 ] biological imaging, [ 11‐13 ] and anti‐counterfeiting. [ 14‐16 ] Generally, organic luminogens in a single component seldom exhibit persistent phosphorescence at ambient conditions due to their intrinsic spin‐forbidden intersystem crossing (ISC) from the lowest single state (S 1 ) to the triplet state (T n ) as well as their ultrafast triplet exciton deactivation.…”

Organic room-temperature phosphorescence materials for bioimaging

“…Organic room-temperature phosphorescence (RTP) materials with long afterglow properties have received widespread attention as smart materials for biological imaging. [1][2][3][4][5] Taking advantage of optical bioimaging technology, [6][7][8][9] RTP materials exhibit higher spatiotemporal resolution, compared to conventional imaging modalities such as magnetic resonance imaging (MRI), computed tomography (CT) and positron emission tomography (PET). In addition, the long lifetime characteristics of RTP materials dissolve the interference of biological autofluorescence in traditional optical bioimaging, permitting in vivo imaging without real-time external excitation.…”