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The titer of anti‐severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) neutralizing antibodies (NAbs) in the human body is an essential reference for evaluating the acquired protective immunity and resistance to SARS‐CoV‐2 infection. In this study, a fluorescence‐quenching lateral flow immunoassay (FQ‐LFIA) is established for quantitative detection of anti‐SARS‐CoV‐2 NAbs in the sera of individuals who are vaccinated or infected within 10 min. The ultrabright aggregation‐induced emission properties encapsulated in nanoparticles, AIE490NP, are applied in the established FQ‐LFIA with gold nanoparticles to achieve a fluorescence "turn‐on" competitive immunoassay. Under optimized conditions, the FQ‐LFIA quantitatively detected 103 positive and 50 negative human serum samples with a limit of detection (LoD) of 1.29 IU mL−1. A strong correlation is present with the conventional pseudovirus‐based virus neutralization test (R2 = 0.9796, P < 0.0001). In contrast, the traditional LFIA with a "turn‐off" mode can only achieve a LoD of 11.06 IU mL−1. The FQ‐LFIA showed excellent sensitivity to anti‐SARS‐CoV‐2 NAbs. The intra‐ and inter‐assay precisions of the established method are below 15%. The established FQ‐LFIA has promising potential as a rapid and quantitative method for detecting anti‐SARS‐CoV‐2 NAbs. FQ‐LFIA can also be used to detect various biomarkers. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) is recognized to be a promising strategy for anticancer treatment. Considering the progressive application of PDT in clinical trials, highly efficient photosensitizers (PSs) are in strong demand. Aggregation‐induced emission (AIE) based PSs are promising phototheranostic materials for tumor imaging and PDT due to their high fluorescence and photosensitizing efficiency. Herein, a PS, TPA‐2BCP with AIE characteristics is developed by adopting an acceptor‐π‐donor‐π‐acceptor (A–π–D–π–A) structure. However, the accumulation of ionic PSs in the tumor is poor due to non‐specific interactions with bio‐molecules. Therefore, we use a carboxyl‐rich polymer material, polyacrylate polyethylene glycol block copolymer (PEG‐b‐PAA) to encapsulate the cationic PSs into nanoparticles through ionic interactions. The cationic groups are blocked and the generated PS nanoparticles can accumulate well in the tumor site in vivo. Meanwhile, the photosensitizing efficiency of the PS is further enhanced in the nanoparticle format. The tumor growth can be obviously inhibited under 530 nm laser irradiation, demonstrating its potential application in antitumor PDT. [ABSTRACT FROM AUTHOR]

[Display omitted] • Summarizing the targeted AIE photosensitizers (PSs) and tumor microenvironment activated AIE PSs for enhancing the intraoperative safety of photodynamic therapy (PDT). • Discussing two-photon excitable AIE PSs for precise PDT with decreased side effects. • Reviewing the degradable AIE PSs, including the bio-degradable ones and self-degradable ones, for improving the postoperative safety of PDT. • Analyzing the challenges and opportunities confronted by safe PDT. Photodynamic therapy (PDT) is emerging as a powerful tool in tumor treatment due to its unique advantages of being minimally invasive and universally applicable. Photosensitizers (PSs) play a crucial role in PDT, and those with aggregation-induced emission (AIE) have been developed to enhance fluorescence and improve photosensitization under physiological conditions for image-guided PDT. However, the non-specific distribution of PSs during PDT and their prolonged retention in the body after PDT can result in damage to normal tissues upon exposure to light, leading to the occurrence of severe side effects. Therefore, this review systematically summarized the latest advances in designing new AIE PSs to enhance the safety of PDT. In particular, some strategies of targeted PSs, responsive turn-on PSs, and two-photon excitable PSs to enhance the intraoperative safety, as well as the strategy of degradable PSs to enhance the postoperative safety were focused. [ABSTRACT FROM AUTHOR]

• High-performance tracking of BEVs in living systems has been realized with an AIEgen. • The probe can illuminate BEVs and shows remarkable merits over traditional methods. • The spatial and temporal distributions of BEVs within host can be clearly visualized. The nano-sized, membrane-enclosed bacterial extracellular vesicles (BEVs) released by bacteria are now regarded as important mediators involved in various physiological and pathological processes of human. To elucidate their roles in bacteria-to-host communication, methods for visualizing and tracking of these nano-vesicles are crucial, but ideal means are lacking currently. In this work, we report the development of a bioprobe, DPASP, for BEV bioimaging with superior performance. DPASP can target BEVs with boosted fluorescence due to its aggregation-induced emission (AIE) attribute, which allows BEV labeling with a high signal-to-background ratio. For BEV imaging, DPASP outperforms the commercial dyes in terms of labeling efficiency, retention time, photostability, and biocompatibility. The applications of DPASP in studying the spatial and temporal distributions of E. coli -derived BEVs within living cells and mice were also demonstrated. The approach developed here provides a valuable tool to better understand the roles of BEVs in health and diseases. [ABSTRACT FROM AUTHOR]

• High-performance tracking of BEVs in living systems has been realized with an AIEgen. • The probe can illuminate BEVs and shows remarkable merits over traditional methods. • The spatial and temporal distributions of BEVs within host can be clearly visualized. The nano-sized, membrane-enclosed bacterial extracellular vesicles (BEVs) released by bacteria are now regarded as important mediators involved in various physiological and pathological processes of human. To elucidate their roles in bacteria-to-host communication, methods for visualizing and tracking of these nano-vesicles are crucial, but ideal means are lacking currently. In this work, we report the development of a bioprobe, DPASP, for BEV bioimaging with superior performance. DPASP can target BEVs with boosted fluorescence due to its aggregation-induced emission (AIE) attribute, which allows BEV labeling with a high signal-to-background ratio. For BEV imaging, DPASP outperforms the commercial dyes in terms of labeling efficiency, retention time, photostability, and biocompatibility. The applications of DPASP in studying the spatial and temporal distributions of E. coli -derived BEVs within living cells and mice were also demonstrated. The approach developed here provides a valuable tool to better understand the roles of BEVs in health and diseases. [ABSTRACT FROM AUTHOR]

The level of anti-SARS-CoV-2 neutralizing antibodies (NAb) is an indispensable reference for evaluating the acquired protective immunity against SARS-CoV-2. Here, we established an ultrabright nanoparticles-based lateral flow immunoassay (LFIA) for one-step rapid semi-quantitative detection of anti-SARS-CoV-2 NAb in vaccinee's serum. Once embedded in polystyrene (PS) nanoparticles, the aggregation-induced emission (AIE) luminogen, AIE 490 , exhibited ultrabright fluorescence due to the rigidity of PS and severe inhibition of intramolecular motions. The ultrabright AIE 490 -PS nanoparticle was used as a fluorescent marker of LFIA. Upon optimized conditions including incubation time, concentrations of coated proteins and conjugated nanoparticles, amounts of antigens modified on the surface of nanoparticles, dilution rate of serum samples, and so on, the ultrabright nanoparticles-based LFIA could accurately identify 70 negative samples and 63 positive samples from human serum (p < 0.0001). The intra- and inter-assay precisions of the established method are above 13% and 16%, respectively. The established LFIA has tremendous practical value of generalization as a rapid semi-quantitative detection method of anti-SARS-CoV-2 NAb. Meanwhile, the AIE 490 -PS nanoparticle is also promising to detect many other analytes by altering the protein on the surface. [ABSTRACT FROM AUTHOR]

The increasing resistance among fungi to antimicrobials are posing global threats to health. Early treatment with appropriate antifungal drugs guided by the antifungal susceptibility testing (AFST) can dramatically reduce the mortality of severe fungal infections. However, the long test time (24–48 h) of the standard AFSTs cannot provide timely results due to the slow growth of the pathogen. Herein, we report a new AFST that is independent of growth rate analysis using a luminogen with aggregation-induced emission characteristics (AIEgen) named DMASP. DMASP is a water-soluble small-molecule probe that can readily penetrate the dense fungal cell wall. Based on its mitochondria-targeting ability and AIE characteristics, fungal activity can be dynamically indicated via real-time fluorescence monitoring. This allows fungal susceptibility to various antimicrobials to be assessed within 12 h in a wash-free, one-step manner. This method may serve as a promising tool to rapidly detect possible drug-resistant fungal strain and guide the precise use of antimicrobial against fungal diseases. [Display omitted] [ABSTRACT FROM AUTHOR]