Ca2+ Induced Crosslinking of AIE-Active Polyarylene Ether Nitrile into Fluorescent Polymeric Nanoparticles for Cellular Bioimaging

Novel AIE-Active Polyarylethersulfone Polymers Incorporating Tetraphenylethene for Enhanced Fluorescence

Aggregation-induced emission (AIE) materials have gained significant attention for their unique fluorescence enhancement in the aggregated state. However, combining rigid polymers with AIE molecules to enhance luminescent properties remains to be investigated. In this work, two novel AIE-active polyarylethersulfone (PAES) derivatives are synthesized by incorporating tetraphenylethene (TPE) into either the side chain or main chain of PAES, resulting in side-chain polyarylethersulfone-tetraphenylethene (PAES-TPE) and main-chain polyarylethersulfone-tetraphenylethene (m-PAES-TPE), respectively. These derivatives are designed to investigate the influence of the rigid polymer backbone on the AIE properties of TPE. The incorporation of TPE into PAES resulted in a notable redshift in fluorescence emission compared to pure TPE. Notably, m-PAES-TPE50%, a polymer with 50% molar content of TPE, exhibited a fluorescence quantum yield to 57.43%, more than twice that of TPE powder. Thermal analysis showed that both PAES-TPE and m-PAES-TPE have excellent thermal stability and temperature-dependent fluorescence. Additionally, these materials are processed into hydrophobic nanoparticles, and in vitro experiments demonstrated good fluorescence properties and biocompatibility for cancer cell bioimaging. This work highlights the potential of rigid AIE-active PAES derivatives for advanced bioimaging applications.

Recent Advances in Aggregation-Induced Emission Active Materials for Sensing of Biologically Important Molecules and Drug Delivery System

The emergence and development of aggregation induced emission (AIE) have attracted worldwide attention due to its unique photophysical phenomenon and for removing the obstacle of aggregation-caused quenching (ACQ) which is the most detrimental process thereby making AIE an important and promising aspect in various fields of fluorescent material, sensing, bioimaging, optoelectronics, drug delivery system, and theranostics. In this review, we have discussed insights and explored recent advances that are being made in AIE active materials and their application in sensing, biological cell imaging, and drug delivery systems, and, furthermore, we explored AIE active fluorescent material as a building block in supramolecular chemistry. Herein, we focus on various AIE active molecules such as tetraphenylethylene, AIE-active polymer, quantum dots, AIE active metal-organic framework and triphenylamine, not only in terms of their synthetic routes but also we outline their applications. Finally, we summarize our view of the construction and application of AIE-active molecules, which thus inspiring young researchers to explore new ideas, innovations, and develop the field of supramolecular chemistry in years to come.

Recent Advances in AIEgens for Metal Ion Biosensing and Bioimaging

Metal ions play important roles in biological system. Approaches capable of selective and sensitive detection of metal ions in living biosystems provide in situ information and have attracted remarkable research attentions. Among these, fluorescence probes with aggregation-induced emission (AIE) behavior offer unique properties. A variety of AIE fluorogens (AIEgens) have been developed in the past decades for tracing metal ions. This review highlights recent advances (since 2015) in AIE-based sensors for detecting metal ions in biological systems. Major concerns will be devoted to the design principles, sensing performance, and bioimaging applications.

An Immunosensor Based on Au-Ag Bimetallic NPs Patterned on a Thermal Resistant Flexible Polymer Substrate for In-Vitro Protein Detection

Nanosensors based on flexible polymers have emerged as powerful tools for next generation smart devices in the recent years. Here, we report a facile protocol to fabricate an immunosensor supported by a thermally resistant flexible polymer substrate (polyarylene ether nitrile, PEN). The immunosensor is a localized surface plasmon resonance (LSPR) optical sensor for in-vitro protein detection based on anti-body coated gold-silver bimetallic nanoparticles (Au-Ag NPs) immobilized on a PEN substrate. Plasmonic spectroscopy and morphological characterization show that the Au-Ag NPs essentially exhibit a more uniform size distribution and higher quality factors than those from single-component Au NPs. Furthermore, it should be noted that the robust PEN substrate in this nanosensor acts a flexible substrate to support Au-Ag NPs and immobilize the nanoparticles via quick thermal annealing at 290 °C. Thanks to these merits, a prostate-specific antigen (PSA) concentration as low as 1 ng/mL can be specifically discriminated via the prepared PEN/Au-Au NPs, which confirms that the protocol reported in this work can be readily adapted for the construction of various flexible immunosensors for different applications.

Scalable Fabrication of Metallopolymeric Superstructures for Highly Efficient Removal of Methylene Blue

Metallopolymeric superstructures (MPS) are hybrid functional materials that find wide applications in environmental, energy, catalytic and biomedical-related scenarios, while their fabrication usually suffers from the complicated polymerization between monomeric ligands and metal ions. In this work, we have developed a facile one-step protocol to fabricate metallopolymeric superstructures with different morphology including nanospheres, nanocubes, nanorods, and nanostars for environmental remediation application. Specifically, we have firstly synthesized the amphiphilic block copolymers (BCP) bearing hydrophobic aromatic backbone and hydrophilic pendent carboxylic/sulfonic groups, which have been subsequently transformed into MPS via the metal ions mediated self-assembly in mixed solution of dimethylformamide (DMF) and H2O. Based on SEM, FTIR, XRD and XPS characterization, we have revealed that the fine morphology and condensed structures of MPS can be modulated via the metal ions and BCP concentration, and the obtained MPS can be employed as efficient adsorbents for the removal of methylene blue with maximum adsorption capacity approaching 936.13 mg/g.

Constructing Artificial Light-Harvesting Systems by Covalent Alignment of Aggregation-Induced Emission Molecules

The characteristics of chloroplasts harvesting solar energy and conducting energy transfer have inspired chemists to mimic similar processes. However, accurate manipulation to gain regularly displayed antenna chromophores in mimicking chloroplasts is a great challenge. Herein, a rational design is presented that combines orderly arranged chromophores with aggregation-induced emission (AIE) to develop artificial light-harvesting systems. Tetraphenyl ethylene (TPE) molecules, which exhibited strong AIE properties, are considered as building blocks to fabricate high emissive 2D nanosheets and nanovesicles, respectively. Furthermore, the well-aligned TPE molecules are also developed as donor chromophores in light-harvesting processes. After subsequent surface modification by porphyrin molecules as acceptor chromophores, an efficient light-harvesting system has been integrally constructed. This study demonstrates a novel strategy to utilize AIE feature to mimic chloroplasts process in nature.

Polymeric Janus Nanoparticles: Recent Advances in Synthetic Strategies, Materials Properties, and Applications

Polymeric Janus nanoparticles with two sides of incompatible chemistry have received increasing attention due to their tunable asymmetric structure and unique material characteristics. Recently, with the rapid progress in controlled polymerization combined with novel fabrication techniques, a large array of functional polymeric Janus particles are diversified with sophisticated architecture and applications. In this review, the most recently developed strategies for controlled synthesis of polymeric Janus nanoparticles with well-defined size and complex superstructures are summarized. In addition, the pros and cons of each approach in mediating the anisotropic shapes of polymeric Janus particles as well as their asymmetric spatial distribution of chemical compositions and functionalities are discussed and compared. Finally, these newly developed structural nanoparticles with specific shapes and surface functions orientated applications in different domains are also discussed, followed by the perspectives and challenges faced in the further advancement of polymeric Janus nanoparticles as high performance materials.