Thermoluminescence

Physics

Nanotechnology

Organic chemistry

Optics

Absorption (acoustics)

Phosphorescent organic light-emitting diode

Luminescence

Excited state

Phosphorescence

Nanoparticle

Composite material

Nuclear physics

Chemistry

Metallurgy

Materials science

Biocompatibility

Aggregation-induced emission

Biological imaging

Molecule

Optoelectronics

Photochemistry

Fluorescence

Persistent luminescence

Nature Communications

Pure organic room-temperature phosphorescent (RTP) materials have been suggested to be promising bioimaging materials due to their good biocompatibility and long emission lifetime. Herein, we report a class of RTP materials. These materials are developed through the simple introduction of an aromatic carbonyl to a tetraphenylpyrrole molecule and also exhibit aggregation-induced emission (AIE) properties. These molecules show non-emission in solution and purely phosphorescent emission in the aggregated state, which are desirable properties for biological imaging. Highly crystalline nanoparticles can be easily fabricated with a long emission lifetime (20 μs), which eliminate background fluorescence interference from cells and tissues. The prepared nanoparticles demonstrate two-photon absorption characteristics and can be excited by near infrared (NIR) light, making them promising materials for deep-tissue optical imaging. This integrated aggregation-induced phosphorescence (AIP) strategy diversifies the existing pool of bioimaging agents to inspire the development of bioprobes in the future.

Rational design of pyrrole derivatives with aggregation-induced phosphorescence characteristics for time-resolved and two-photon luminescence imaging