Coemissive luminescent nanoparticles combining aggregation-induced emission and quenching dyes prepared in continuous flow

Dynamic Flow-Assisted Nanoarchitectonics

The solution to societal problems such as energy, environmental, and biomedical issues lies in the development of functional material systems with the capacity to address these problems. In the course of human development, we are entering a new era in which nanostructure control is considered in the major development of functional materials. The new concept of nanoarchitectonics is particularly significant in this regard, as it comprehensively promotes further development of nanotechnology and its fusion with materials chemistry. The integration of nanoscale phenomena and macroscopic actions is imperative for practical production of functional materials with nanoscale structural precision. This review focuses on dynamic flow-assisted nanoarchitectonics, wherein we explore the organization and control of functional structures by external mechanical stimuli, predominantly fluid flow. The review then proceeds to select some examples and divide them into categories for the purpose of discussion: structural organization by (i) natural flow, (ii) flow or stress created with artificial equipment or devices (forced flow), and (iii) flow at a specific field, namely interfaces, that is, layer-by-layer (LbL) assembly and the LB method. The final perspective section discusses the future research directions and requirements for dynamic flow-assisted nanoarchitectonics. The meaningful and effective use of nanotechnology and nanoarchitectonics in materials science is set to be a major area of focus in the future, and dynamic flow-assisted nanoarchitectonics is poised to play a significant role in achieving this objective.

Uncovering the Fluctuation of Peroxynitrite during Early Embryonic Development Using an Integrative Nanobeacon

Embryonic development is the beginning of life, and various kinds of bioactive molecules are implicated in this crucial process. Especially in its early stage, some important biochemical reactions regulating physiological balance may be resuscitated. Thus, revealing the dynamic changes of bioactive molecules during early embryonic development is crucial to the elucidation of biological phenomena. Peroxynitrite (ONOO-) is a typical signaling molecule in intercellular communication. However, up to now, no work has studied the fluctuation of ONOO- during early embryonic development due to its low content, especially in mammals. Herein, a polymeric nanobeacon that integrates an ONOO--responsive degradable scaffold and a fluorescence amplification module, named IFN, was designed to selectively sense embryonic ONOO- with high sensitivity. By virtue of the specific dye, ONOO- was sensitively detected in the range of 0-4.5 μM with a detection limit of 20.4 nM. From the attractive embryonic results, a sudden increase in ONOO- content after fertilization was observed in a mammalian model, while the level of ONOO- decreased slightly at the four-cell and eight-cell stages, finally reaching an equilibrium throughout the morula and blastocyst stages. This phenomenon is due to the resuscitation of ovotids, the activation of some life events by fertilization, and the subsequent establishment of physiological balance. This work not only suggests that ONOO- plays a positive role in normal embryonic development but also highlights the molecular events occurring at the initial phase of life. Furthermore it opens up new avenues for monitoring chemical changes during mammalian embryonic development.

Artificial light harvesting system of CM6@Zn-MOF nanosheets with highly enhanced photoelectric performance

As donors for effective energy transfer, metal-organic frameworks (MOFs) have attracted the attention of many experts in the field of artificial light-harvesting materials. This study introduces a novel two-dimensional Zn-MOF, synthesized using flexible 1,3-phenyldiacetic acid (H2mpda) and rigid 1,3,5-tris(1-imidazolyl)benzene (tib) as organic ligands. Through atomic force microscopy (AFM), we have determined the monolayer thickness of this novel material to be 5 nm. Achieving two-dimensional Zn-MOF nanosheets with large BET surface area was made possible by employing ultrasonic stripping techniques. The fluorescence emission spectrum of Zn-MOF nanosheets overlaps with the UV-vis absorption spectrum of coumarin 6 (CM6), so they can be used as a donor and acceptor for fluorescence resonance energy transfer (FRET) to construct an artificial light-harvesting system (ALHS). Compared with single crystal Zn-MOF, CM6@Zn-MOF(2) has a larger BET surface area (41 m2/g), higher quantum yield (Φfl, 30.56 %), narrower energy gap (Eg, 2.87 eV), and the light-harvesting range extends to the visible green light area. Notably, CM6@Zn-MOF(2) demonstrates a robust photocurrent response, characterized by a photocurrent on/off ratio (Ilight/Idark) of 21, and a maximum photocurrent density that surpasses that of pure Zn-MOF (2.25:1). This study successfully designed a high-performance photoelectric conversion material CM6@Zn-MOF(2), which laid a certain theoretical foundation for new artificial optical acquisition systems and electrochemical material selection.

Efficient green synthesis of biocompatible MPN fluorescent microspheres via hydrophobic-force-driven strategy for enhanced immunochromatographic assays

The unique fluorescence properties of aggregation-induced emission (AIE) fluorescent microspheres (FMs) make them ideal signal markers. Traditional synthesis methods are complex, labor-intensive, and hazardous, leading to AIEFMs that lack biocompatibility and require further modification for immunoprobe preparation. This study introduces a novel hydrophobic force-driven method for rapid synthesis of highly biocompatible FMs (H-FMs), demonstrating their benefits in immunochromatographic assay (ICA) applications. The metal-polyphenol network (MPN) shell around the AIEgen core structure of H-FMs is quickly and safely formed by depositing MPN onto AIEgen nano-aggregates, achieving high dye utilization, affordability, and design flexibility, while producing H-FMs with fluorescence across 300-800 nm. The excellent biocompatibility of H-FMs eliminates the need for additional modifications, allowing antibodies to be coupled swiftly (within 10 min) with a high coupling efficiency of 93.4 %. The resulting immunoprobes exhibit strong target recognition and 90.6 % fluorescence retention over 30 days. These features support their application in double antibody sandwich and competitive ICA formats, with detection limits of 9.62 × 10² CFU/mL for E. coli O157:H7 and 0.0081 ng/mL for AFM1. This study provides new insights into designing fluorescent probes for safety monitoring of hazardous materials in the environment.

Efficient Self-Sorting Behaviours of Metallacages with Subtle Structural Differences

Investigating the self-sorting behaviour of assemblies with subtle structural differences is a captivating yet challenging endeavour. Herein, we elucidate the unusual self-sorting behaviour of metallacages with subtle structural differences in batch reactors and microdroplets. Narcissistic self-sorting of metallacages has been observed for two ligands with identical sizes, shapes, and symmetries, with only minor differences in the substituted groups. In particular, the self-sorting process in microdroplets occurs within 1 min at room temperature, in stark contrast to batch reactors, which require equilibration for 30 min. To reveal the mechanism of self-sorting and the role of microdroplets, we conducted a series of experiments and theoretical calculations, including competitive self-assembly, cage-to-cage transformation, control experiments involving model metallacages with larger cavities, noncovalent interaction analysis, and root mean square deviation (RMSD) analysis. This research demonstrates an unusual case of self-sorting of very similar assemblies and provides a new strategy for facilitating the self-sorting efficiency of supramolecular systems.

Phospholipids of inhaled liposomes determine the in vivo fate and therapeutic effects of salvianolic acid B on idiopathic pulmonary fibrosis

Since phospholipids have an important effect on the size, surface potential and hardness of liposomes that decide their in vivo fate after inhalation, this research has systematically evaluated the effect of phospholipids on pulmonary drug delivery by liposomes. In this study, liposomes composed of neutral saturated/unsaturated phospholipids, anionic and cationic phospholipids were constructed to investigate how surface potential and the degree of saturation of fatty acid chains determined their mucus and epithelium permeability both in vitro and in vivo. Our results clearly indicated that liposomes composed of saturated neutral and anionic phospholipids possessed high stability and permeability, compared to that of liposomes composed of unsaturated phospholipids and cationic phospholipids. Furthermore, both in vivo imaging of fluorescence-labeled liposomes and biodistribution of salvianolic acid B (SAB) that encapsulated in liposomes were performed to estimate the effect of phospholipids on the lung exposure and retention of inhaled liposomes. Finally, inhaled SAB-loaded liposomes exhibited enhanced therapeutic effects in a bleomycin-induced idiopathic pulmonary fibrosis mice model via inhibition of inflammation and regulation on coagulation-fibrinolytic system. Such findings will be beneficial to the development of inhalable lipid-based nanodrug delivery systems for the treatment of respiratory diseases where inhalation is the preferred route of administration.

Recent developments in lignin-based fluorescent materials

Biomass-based fluorescent materials are an alternative to plastic-based materials for their multifunctional applications. Lignin, an inexpensive and easily available raw material, demonstrates outstanding environment-responsive properties such as pH, metal ions, dyes sensing, bioimaging and so on. To date, only a little work has been reported on the synthesis of lignin-based fluorescent materials. In this review report, synthetic approaches and light-responsive applications of lignin-based fluorescent carbon dots and other materials are summarized. The results reveal that lignin-based fluorescent carbon dots are prepared by hydrothermal method, exhibit small size <10 nm, reveal significant quantum yield, biocompatibility, non-toxicity, photostability and display substantial tunable emission and can be efficiently employed for sensing, bioimaging and energy storage applications. Finally, the forthcoming challenges, investigations, and options open for the chemical and/or physical modification of lignin into fluorescent materials for future applications are well-addressed. To our knowledge, this is the first comprehensive review report on lignin-based fluorescent materials and their light-responsive applications. In addition, this review will attract remarkable consideration and thrust for the researchers and biochemical technologists working with the preparation of lignin-based fluorescent materials for broad applications.

Bioinspired polymeric supramolecular columns as efficient yet controllable artificial light-harvesting platform

Light-harvesting is an indispensable process in photosynthesis, and researchers have been exploring various structural scaffolds to create artificial light-harvesting systems. However, achieving high donor/acceptor ratios for efficient energy transfer remains a challenge as excitons need to travel longer diffusion lengths within the donor matrix to reach the acceptor. Here, we report a polymeric supramolecular column-based light-harvesting platform inspired by the natural light-harvesting of purple photosynthetic bacteria to address this issue. The supramolecular column is designed as a discotic columnar liquid crystalline polymer and acts as the donor, with the acceptor intercalated within it. The modular columnar design enables an ultrahigh donor/acceptor ratio of 20000:1 and an antenna effect exceeding 100. Moreover, the spatial confinement within the supramolecular columns facilitates control over the energy transfer process, enabling dynamic full-color tunable emission for information encryption applications with spatiotemporal regulation security.

High-Performance Fluorescent Microspheres Based on Fluorescence Resonance Energy Transfer Mode for Lateral Flow Immunoassays

The label with a large Stokes shift and strong fluorescence properties could improve the sensitivity of the lateral flow immunoassay (LFIA). Herein, two aggregation-induced emission (AIE) luminogens with spectral overlap were encapsulated in polymers by using the microemulsion method as a label, and the construction of a fluorescence resonance energy transfer mode was further verified via theoretical calculation and spectral analysis. Satisfactorily, the doped AIE polymer microspheres (DAIEPMs) exhibited a large Stokes shift of 285 nm and a 10.8-fold fluorescence enhancement compared to those of the AIEPMs loaded with acceptors. Benefiting from the excellent optical performance, DAIEPMs were applied to the LFIA for sensitive detection of chlorothalonil, which is an organochlorine pesticide. The limit of detection of the proposed DAIEPMs-LFIA was 1.2 pg/mL, which was 4.8-fold and 11.6-fold lower than those of quantum dot bead LFIA and gold nanoparticle LFIA, respectively. This work provides a new strategy to improve the optical properties of fluorescent materials and construct a sensitive and reliable detection platform.

Application of Nanomaterials in the Production of Biomolecules in Microalgae: A Review

Nanomaterials (NMs) are becoming more commonly used in microalgal biotechnology to empower the production of algal biomass and valuable metabolites, such as lipids, proteins, and exopolysaccharides. It provides an effective and promising supplement to the existing algal biotechnology. In this review, the potential for NMs to enhance microalgal growth by improving photosynthetic utilization efficiency and removing reactive oxygen species is first summarized. Then, their positive roles in accumulation, bioactivity modification, and extraction of valuable microalgal metabolites are presented. After the application of NMs in microalgae cultivation, the extracted metabolites, particularly exopolysaccharides, contain trace amounts of NM residues, and thus, the impact of these residues on the functional properties of the metabolites is also evaluated. Finally, the methods for removing NM residues from the extracted metabolites are summarized. This review provides insights into the application of nanotechnology for sustainable production of valuable metabolites in microalgae and will contribute useful information for ongoing and future practice.

Microreactor-based micro/nanomaterials: fabrication, advances, and outlook

Micro/nanomaterials are widely used in optoelectronics, environmental materials, bioimaging, agricultural industries, and drug delivery owing to their marvelous features, such as quantum tunneling, size, surface and boundary, and Coulomb blockade effects. Recently, microreactor technology has opened up broad prospects for green and sustainable chemical synthesis as a powerful tool for process intensification and microscale manipulation. This review focuses on recent progress in the microreactor synthesis of micro/nanomaterials. First, the fabrication and design principles of existing microreactors for producing micro/nanomaterials are summarized and classified. Afterwards, typical examples are shown to demonstrate the fabrication of micro/nanomaterials, including metal nanoparticles, inorganic nonmetallic nanoparticles, organic nanoparticles, Janus particles, and MOFs. Finally, the future research prospects and key issues of microreactor-based micro/nanomaterials are discussed. In short, microreactors provide new ideas and methods for the synthesis of micro/nanomaterials, which have huge potential and inestimable possibilities in large-scale production and scientific research.