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Nano-assemblies have wide applications in biomedicine, functional coatings, Pickering emulsifiers, hydrogels, and so forth. The preparation of assemblies mainly utilizes the polymerization-induced self-assembly (PISA) method, which can produce high-concentration nanoscale assemblies in one step. However, the initiation processes of most reported PISA are limited to thermal initiation. Here, we reported two green and efficient methods for synthesizing nano-assemblies with various morphologies using ultrasound (20 kHz)/ microwave (500 W) assisted aqueous-phase RAFT-PISA in 3 h and 1 h. Cyclodextrin (CD) and styrene (St) nucleating monomer were complexed in a 1:1 ratio. Then, using Poly (ethylene glycol) methyl ether as the macromolecular reversible addition-fragmentation chain transfer (RAFT) agent (PEG-CTA) to control the CD/St complexes, the conversion rate of St monomer was respectively 27 %–60 %, 20 %–30 % within 3 h and 1 h under ultrasonics/microwave assisted PISA. Results showed that the morphologies of the assemblies are not only related to the length of PS block, but also to the assistance types and the remaining monomer concentration. The results showed that only PEG45-b-PS90 and PEG45-b-PS241 assemblies prepared by ultrasonics assisted PISA form evolved lamellaes and vesicles (100 nm), which break through the limitation of kinetic freezing. But the ultrasonic reaction on morphology of assemblies is not all favourable. For one thing, it can promote the movement of particles; for another, it makes reverse morphology transformation and sphere is preferred morphology. Therefore, the main reason of morphology evolution is the remaining monomer concentration of PEG45-b-PS90 and PEG45-b-PS241 assemblies reaches to 55 %–65 %, which promoting the segment movement. The results showed that the morphology of the assemblies prepared by microwave assisted PISA changed from spherical micelles to short rods, and finally to vesicles (120–140 nm) as the length of hydrophobic PS block increases. The kinetic freezing problem was solved in microwave-assisted PISA due to the action of microwaves and more remaining monomer concentration. Both them can boost particles movement.

Abstract Cancer is one of the most fatal diseases for decades. Aggregation‐induced emission luminogens (AIEgens) have been recently used as molecular imaging or therapeutic agents in cancers, due to the advantages of large Stokes shift, high quantum yield, great biocompatibility, and strong photostability. AIEgens can specifically target different types of cancer via diverse targeting strategies. AIEgen‐based fluorescence imaging, especially near‐infrared imaging, demonstrated deep penetration and suitable signal‐to‐noise ratio, which allows reliable in vivo cancer imaging. Combined with other imaging modalities, AIEgen‐based multimodal imaging could provide multidimensional cancer hallmarks from different perspectives. In addition, AIEgen‐based phototherapy can be used for photodynamic therapy and photothermal therapy, which facilitate ablation of cancer cells with good biosafety and high therapeutic effects in vivo. AIEgens nanoparticles fabricated with some specific chemicals, drugs, or siRNA, could display synergistic therapeutic effects for cancers. This paper comprehensively describes the current status and future perspectives of AIEgens, which have showed a great potential for the future preclinical and clinical translation on in vivo molecular imaging and theranostics in cancer.

Aggregation-induced emission (AIE) is exploited for several optoelectronic applications, but synthesizing molecules that respond to multiple stimuli is challenging. Here, the authors report a hydroquinone bearing an AIE-active core that responds to both redox and pH changes.

Fluorescent sensor has demonstrated to be a facile and effective method to detect heavy metal ions owing to its unique characteristics such as simplicity, ease of operation and cost-effectiveness. In this work, a novel fluorescent probe with aggregation-induced emission (AIE) feature that contains an amide ligand base on the tetraphenylethylene (TPE) dye was designed and successfully synthesized. The utilization of the AIE-active fluorescent probe (named as FDPA) for detection of Cu2+ in aqueous solution has also been examined. We demonstrated that the resultant AIE-active molecule displays amphiphilic property and can self-assemble in aqueous solution with remarkable enhancement of fluorescent intensity owing to its AIE feature. The detection limit of probe for Cu2+ determination is 6.11 × 10−9 M and shows excellent selectivity in the presence of competitive ions. This work provides a useful route to overcome the fluorescence quenching of conventional fluorescent probes in aqueous solution and an elegant way to prepare fluorescent probes with better fluorescence properties.

Personal mobile devices form an integral part of business activities today. Mobile devices, nevertheless, pose various security issues and data privacy threats, which require a close attention. The rational choice theory was utilized to examine the determinants of employees’ security behavior in relation to mobile device usage. Employees were postulated to rationally evaluate the costs and benefits of mobile security measures and decide on the option that is perceived to provide the best expected outcome. Twelve out of thirteen hypotheses examined in this study were found to be significant. We also hypothesized that demographics and work-related variables significantly affect employees’ mobile security practices, examined using ordinal logistic regression analysis. The findings indicate the efficacy of the rational choice theory in explaining mobile security behavior. Security inconvenience has been found to be a significant cost to information security measures. Moreover, the findings also showed the influence of gender, job function, past security experience, and perceived risk on the dependent variable. In conclusion, we would like to draw considerable attention to the contribution of security awareness programs and security training to good mobile security behaviors.

Biological tissues can automatically repair themselves after damage. Examples include skin, muscle, soft tissue, etc. Inspired by these living tissues, numerous self-healing hydrogels have been developed recently. Chitosan-based self-healing hydrogels constructed via dynamic imine bonds have been widely studied due to their simple preparation, good biocompatibility, and automatic reparability under physiological conditions. In this mini-review, we highlighted chitosan-based self-healing hydrogels based on dynamic imine chemistry, and provided an overview of the preparation of these hydrogels and their bioapplications in cell therapy, tumor therapy, and wound healing.

In recent years, biopolymers are highly desired for their application in optic electronic devices, because of their unique structure and fantastic characteristics. In this work, a non-volatile memory (NVM) device based on the bio thin-film transistor (TFT) was fabricated through applying a new RNA–CTMA (cetyltrimethylammonium) complex as a gate dielectric. The physicochemical performance, including UV, CD spectral, thermal stability, surface roughness, and microstructure, has been investigated systematically. The RNA–CTMA complex film exhibits strong absorption with a well-defined absorption peak around 260 nm, the RMS roughness is ~2.1 nm, and displayed excellent thermal stability, up to 240 °C. In addition, the RNA–CTMA complex-based memory device shows good electric performance, with a large memory window up to 52 V. This demonstrates that the RNA–CTMA complex is a promising candidate for low cost, low-temperature processes, and as an environmentally friendly electronic device.