Advancements and future perspectives of triphenylamine-based fluorescent probes in biomedical applications

Triphenylamine (TPA)-based fluorescent probes and advanced materials have garnered significant attention in biomedical research owing to their distinctive optoelectronic properties and versatile donor-acceptor (D-A) structural configurations. These materials exhibit excellent photophysical and photochemical behaviors, making them ideal for molecular imaging, disease diagnosis, and therapeutic applications, particularly in phototherapy. TPA derivatives have been engineered to enhance environment-responsive fluorescence, signal-to-noise ratios, and tissue penetration, significantly advancing their theranostic potential. The integration of TPA-based systems with advanced molecular design strategies, such as twisted intramolecular charge transfer (TICT), intramolecular charge transfer (ICT), and Förster resonance energy transfer (FRET), has further improved probe selectivity and sensitivity, enabling precise bioimaging and targeted therapy. This review provides a comprehensive overview of recent developments in TPA-based materials, discussing their structural design, underlying mechanisms, biomedical applications, and future prospects for clinical translation. STATEMENT OF SIGNIFICANCE: Triphenylamine (TPA)-based fluorescent probes and functional materials have emerged as a pivotal class of optoelectronic platforms with significant implications for biomedical imaging, diagnostics, and therapy. Their distinctive donor-acceptor (D-A) structures, coupled with tunable photophysical properties, enable high-contrast fluorescence imaging and efficient light-driven therapeutic interventions, such as photodynamic and photothermal therapy. Recent advancements in molecular design strategies, including aggregation-induced emission (AIE), twisted intramolecular charge transfer (TICT), and Förster resonance energy transfer (FRET), have further enhanced their selectivity, sensitivity, and tissue penetration capabilities, overcoming key limitations of conventional fluorophores. The integration of TPA derivatives into nanostructured platforms has also expanded their applicability, improving biocompatibility and theranostic precision. This review provides a comprehensive analysis of the structural innovations, mechanistic insights, and translational potential of TPA-based materials, offering critical perspectives for their future deployment in biomedical research and clinical applications.