Introduction
Aggregation-induced emission (AIE) refers to the phenomenon that certain luminescent materials exhibit enhanced luminescence in aggregated or solid-state environments. Unlike traditional aggregation-luminescence quenching (ACQ), traditional organic fluorescent molecules can only emit light in dilute solutions, which greatly limits its application in solid luminescent materials. As a new class of luminescent materials, AIE materials have many outstanding advantages such as tunable molecular structure, high molar absorptivity, high brightness, large Stokes shift, good photostability, and good biocompatibility. AIE enables the manufacturing of various efficient luminescent materials, opening up new paradigms in the fields of imaging, sensing, medical therapy, light harvesting, light-emitting devices, and organic electronic devices.
AIE Material Design Strategy
In recent years, the design of AIE materials has become a key strategy in the field of advanced materials science. In order to further increase the emission intensity, the most commonly used method is to enhance the overlap of π-electron and simultaneously form a conjugated system of polyatomic orbitals. However, this approach is often a double-edged sword. Since π-conjugation extension can cause higher fluorescence efficiency, π-conjugated systems may produce better π-π stacking interactions with increasing conjugation. Therefore, when designing AIE molecules, the rationality of the conjugated system should be considered.
It is worth noting that triphenylamine (TPA), hexaphenylsilicone (HPS), tetraphenylethylene (TPE), and distyrylanthracene (DSA) (figure 1) have become prominent AIE luminescent sources due to their ability to restrict intramolecular motion and enhance aggregated state fluorescence [1].
Fig. 1 Chemical structures of TPE, DSA, TPA, and HPS [1].
Applications of AIE Materials
AIE materials have made great strides in various fields due to their unique properties and applications. This article will delve into the diverse applications of AIE materials in chemosensors, biosensors, tissue imaging, and cell imaging.
Chemosensors play a crucial role in detecting and monitoring chemical species in various environments. AIE materials have shown promising applications in chemosensing due to their enhanced emission properties in aggregated states. For instance, recent studies have demonstrated the utilization of AIE luminogens for the selective detection of heavy metal ions in water sources. These materials exhibit enhanced fluorescence upon binding with specific metal ions, providing a sensitive and efficient detection method.
Biosensors are essential tools for detecting biological molecules, pathogens, and biomarkers in biomedical research and diagnostics. AIE materials have shown significant potential in biosensing applications due to their high sensitivity and biocompatibility. These materials can be employed in fluorescent biosensors for detecting various biomolecules, such as proteins, nucleic acids, and enzymes.
Tissue imaging plays a vital role in biomedical research, particularly in visualizing cellular processes and pathological tissues. AIE materials have emerged as promising candidates for tissue imaging applications, offering enhanced signal-to-noise ratios and imaging contrast. By incorporating AIE luminogens into imaging probes, researchers can visualize specific tissues with high precision and sensitivity.
Cell imaging is essential for studying cellular dynamics, organelle structures, and molecular interactions within living cells. AIE materials have revolutionized cell imaging techniques by providing bright and photostable fluorescent probes for tracking cellular processes. These AIE-based probes exhibit minimal background interference and high photo stability, making them ideal for long-term cell imaging studies.
With ongoing advancements in AIE material design and synthesis, Alfa Chemistry remains committed to driving innovation in these key areas and enabling cutting-edge applications in the field of material science and biotechnology. Please feel free to contact us for more information of the AIE materials.
Reference
- Wang, Z.; et al. Conjugated Aggregation-Induced Fluorescent Materials for Biofluorescent Probes: A Review. Biosensors 2023, 13, 159.
