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Copper plays critical roles as a metal active site cofactor and metalloallosteric signal for enzymes involved in cell proliferation and metabolism, making it an attractive target for cancer therapy. In this study, we investigated the efficacy of polydopamine nanoparticles (PDA NPs), classically applied for metal removal from water, as a therapeutic strategy for depleting intracellular labile copper pools in triple-negative breast cancer models through the metal-chelating groups present on the PDA surface. By using the activity-based sensing probe FCP-1, we could track the PDA-induced labile copper depletion while leaving total copper levels unchanged and link it to the selective MDA-MB-231 cell death. Further mechanistic investigations revealed that PDA NPs increased reactive oxygen species (ROS) levels, potentially through the inactivation of superoxide dismutase 1 (SOD1), a copper-dependent antioxidant enzyme. Additionally, PDA NPs were found to interact with the mitochondrial membrane, resulting in an increase in the mitochondrial membrane potential, which may contribute to enhanced ROS production. We employed an in vivo tumor model to validate the therapeutic efficacy of PDA NPs. Remarkably, in the absence of any additional treatment, the presence of PDA NPs alone led to a significant reduction in tumor volume by a factor of 1.66 after 22 days of tumor growth. Our findings highlight the potential of PDA NPs as a promising therapeutic approach for selectively targeting cancer by modulating copper levels and inducing oxidative stress, leading to tumor growth inhibition as shown in these triple-negative breast cancer models.

Summary Activity‐based sensing probes are powerful tools for monitoring enzymatic activities in complex biological samples such as cellular and live animals; however, their application in plants remains challenging. Herein, fourteen activity‐based fluorescent probes were assayed against Arabidopsis O‐methyltransferases (AtOMTs). One probe, 3‐BTD, displayed a high selectivity, reactivity, and fluorescence response toward AtOMTs especially the isoform AtCCoAOMT. We further characterized the features of this probe and explored whether it could be used to detect OMT activities in living plant cells. Our results show that 3‐BTD can be used to visualize OMT activity in Arabidopsis, and no fluorescent signal was observed in the comt/ccoaomt double mutant, indicating that it has good specificity. Interestingly, in contrast to the observation that AtCCoAOMT‐YFP accumulated in both cytoplasm and nucleus, OMT enzymatic activity tracked by 3‐BTD probe was found only in the cytoplasm. This underscores the importance of activity‐based sensing in studying protein function. Moreover, 3‐BTD can be successfully applied in OMT visualization of different plants. This study indicates that 3‐BTD can serve as a potential probe for in situ monitoring the real activity of OMT in multiple plants and provides a strategy for visualizing the activity of other enzymes in plants. [ABSTRACT FROM AUTHOR]

Two‐directional beam‐tracking (2DBT) is a method for phase‐contrast imaging and tomography that uses an intensity modulator to structure the X‐ray beam into an array of independent circular beamlets that are resolved by a high‐resolution detector. It features isotropic spatial resolution, provides two‐dimensional phase sensitivity, and enables the three‐dimensional reconstructions of the refractive index decrement, δ, and the attenuation coefficient, μ. In this work, the angular sensitivity and the spatial resolution of 2DBT images in a synchrotron‐based implementation is reported. In its best configuration, angular sensitivities of ∼20 nrad and spatial resolution of at least 6.25 µm in phase‐contrast images were obtained. Exemplar application to the three‐dimensional imaging of soft tissue samples, including a mouse liver and a decellularized porcine dermis, is also demonstrated. [ABSTRACT FROM AUTHOR]

The enzyme-mimicking nature of versatile nanomaterials proposes a new class of materials categorized as nano-enzymes, ornanozymes. They are artificial enzymes fabricated by functionalizing nanomaterials to generate active sites that can mimic enzyme-like functions. Materials extend from metals and oxides to inorganic nanoparticles possessing intrinsic enzyme-like properties. High cost, low stability, difficulty in separation, reusability, and storage issues of natural enzymes can be well addressed by nanozymes. Since 2007, more than 100 nanozymes have been reported that mimic enzymes like peroxidase, oxidase, catalase, protease, nuclease, hydrolase, superoxide dismutase, etc. In addition, several nanozymes can also exhibit multi-enzyme properties. Vast applications have been reported by exploiting the chemical, optical, and physiochemical properties offered by nanozymes. This review focuses on the reported nanozymes fabricated from a variety of materials along with their enzyme-mimicking activity involving tuning of materials such as metal nanoparticles (NPs), metal-oxide NPs, metal–organic framework (MOF), covalent organic framework (COF), and carbon-based NPs. Furthermore, diverse applications of nanozymes in biomedical research are discussed in detail. [ABSTRACT FROM AUTHOR]

Fluorescence lifetime imaging microscopy (FLIM) opens new dimensions for highly multiplexed imaging in live cells and organisms using differences in fluorescence lifetime to distinguish spectrally identical fluorescent probes. Here, a set of fluorescence‐activating and absorption‐shifting tags (FASTs) capable of modulating the fluorescence lifetime of embedded fluorogenic 4‐hydroxybenzylidene rhodanine (HBR) derivatives is described. It is shown that changes in the FAST protein sequence can vary the local environment of the chromophore and lead to significant changes in fluorescence lifetime. These fluorescence lifetime‐modulating tags enable multiplexed imaging of up to three targets in one spectral channel using a single HBR derivative in live cells and live zebrafish larvae. The combination of fluorescence lifetime multiplexing with spectral multiplexing allows to successfully image six targets in live cells, opening great prospects for multicolor fluorescence lifetime multiplexing. [ABSTRACT FROM AUTHOR]

A new type of material, organic salts in the crystal and crystalline powder state, with both excitation wavelength dependent (Ex‐De) fluorescence and Ex‐De phosphorescence under ambient conditions have been reported. The single component triphenylsulfonium chloride displays tunable fluorescent colors ranging from light purple to sky blue and tunable afterglow colors varying from green to yellowish green, to yellow (lifetimes: 57, 141, 66 ms, afterglow lasting for 2.1, 2.0, 2.3 s). The relationship between the structure and luminescence performance of 17 sulfonium salt derivatives confirms the pivotal roles of both the anions and the electronic and steric effect of substituent factors for luminescence. Single‐crystal analysis reveals that unique ionic bonding and intermolecular interaction can promote an ordered arrangement of organic salts in a crystal state, which then can facilitate molecular aggregation for phosphorescence generation. Theoretical calculations have also confirmed this viewpoint. More importantly, these sulfonium salt derivatives can be used for advanced multimodal anti‐counterfeiting and mitochondrial imaging, respectively. This study has not only expanded the scope of Ex‐De materials but also extended their applications. [ABSTRACT FROM AUTHOR]

In biomedical and optical applications, multifunctional upconverting nanoparticles (UCNPs) play an essential role where non‐invasive temperature sensing and imaging are necessary. UCNPs smaller than 20 nm, which can be excited under 808 nm wavelength, are particularly promising in this area and can be implemented in humans or other mammals. However, new versatile nanoprobes are still needed for biology, especially for challenging studies of small aquatic invertebrates. Such tools allow better monitoring and understanding of their physiology, biochemistry, and ecological responses, which is crucial due to the growing pollution of water reservoirs and climate change. Herein, multifunctional NaYF4:Yb3+, Er3+@NaNdF4:Yb3+ core@shell NPs (15 nm), forming stable aqueous colloids, exhibiting intense emissions under excitation in the first biological window (808 nm), and presenting high thermal sensitivity and resolution related to the thermally coupled energy levels of Er3+ ions, are designed and synthesized. Such properties of UCNPs are further utilized for optical imaging of aquatic invertebrates (Daphnia magna) and temperature detection inside their bodies under 808 nm excitation. This pioneering application of NaYF4:Yb3+, Er3+@NaNdF4:Yb3+ demonstrates the high potential of developed UCNPs for multifunctional applications, especially for bioimaging and temperature sensing within whole organisms. [ABSTRACT FROM AUTHOR]

Advancement in nanotechnology paves new way in nanomedicine via synthesis of various scaffolds bearing multifunctionalities having characteristics of both as diagnostic and therapeutic applications. Quantum dots (QDs) with exceptional luminescent properties exhibited some unbeatable characteristics of small size with ease in surface modifications and thus make them suitable candidates to be used in drug delivery and diagnosis of diseases. Meanwhile, various type of peptides are known in literature for their excellent therapeutic properties and thus make them promising candidates to be used as conjugate partner with the QDs. Highly luminescent properties and surface modifications flexibility of QDs, further urge to use them as promising conjugate partner with many small molecules including peptides and thus found applications in the field of nanomedicines. Thus Peptides ‐QDs conjugates exhibited the properties of both QDs and bioactivity, biocompatibility features of peptides and hence leave behind the limitation of both the individual partners (i. e. QDs and peptides). Thus the combined Peptides‐QDs conjugates acts as theranostic agent for various diseases where these acts as both imaging and drug delivery agent. Hence the present review focused on the theranostic applications of the Peptides‐QDs conjugates in various area of the nanomedicines. Also we focus on the area of improvement and advancement in nanomedicines for the diagnosis and treatment of the diseases in the early stages. [ABSTRACT FROM AUTHOR]

Zirconium nitride (ZrN) nanoparticles (NPs) can offer appealing plasmonic properties for biomedical applications, but the synthesis of nontoxic, water-dispersible nanoformulations exhibiting plasmonic features in the biotransparency window presents a great challenge. Here, we report the synthesis, by methods of laser ablation, of small ZrN-based NPs, which are unique in combining photothermal heating and near-field enhancement in the transparency window. Depending on the synthesis environment, the formed ZrN-based NPs exhibit plasmonic absorption bands with maxima around 660–670 and 610–630 nm, which are largely red-shifted compared to what is expected from pure ZrN NPs. The observed shift is explained by the inclusion of zirconium oxide ZrOx (1 < x < 2) into NP composition and NP coating by naturally formed ZrOx. We then explored biophotonic applications of ZrN NPs. While pure NPs demonstrate their nontoxicity in vitro, their conjugation with anti-HER1 affibody ZHER1:1907 and subsequent photothermal heating with NIR-I laser cause 100% cancer cell death. In addition, profiting from the field enhancement, we demonstrate bioimaging functionality using a designed surface-enhanced Raman scattering probe based on an NP-conjugated azobenzene-CN-OH molecule as a Raman reporter. Combining a strong photothermal effect and the imaging option, laser-synthesized ZrN/ZrOx NPs promise a major advancement of theranostic modalities based on plasmonic nanomaterials. [ABSTRACT FROM AUTHOR]

The equilibrium state of hydrogen sulfide (H2S), a gaseous signaling molecule produced by lysosomal metabolites, in vivo is crucial for cellular function. Abnormal fluctuations in H2S concentration can interfere with the normal function of lysosomes, which has been closely linked to the pathogenesis of a variety of diseases. In view of this, a novel fluorescent probe Lyso-DPP based on 1,3,5-triarylpyrazolines was developed for the precise detection of H2S in lysosomes by using the hydrophilic morpholine moiety as a lysosomal targeting unit, and 2,4-dinitroanisole as a fluorescence-quenching and H2S-responsive unit. The probe cleverly combines the advantages of simple synthesis, sensitive blue fluorescence turn-on with a limit of detection, LOD, of 97.3 nM, good stability, and fast response time (10 min), which makes Lyso-DPP successful in portable monitoring of meat freshness in the form of test strips. Moreover, the excellent biocompatibility and precise targeting capability of the probe Lyso-DPP make it perform well in the monitoring of H2S in lysosomes, living cells, and zebrafish. This work not only provides new technical tools for food quality control but also paves up new ideas for early diagnosis and treatment of H2S-related diseases. [ABSTRACT FROM AUTHOR]

In the human body, carboxylesterases (CEs) play crucial roles in xenobiotic metabolism and lipid homeostasis. But abnormal expression of CEs is highly associated with some diseases, such as hyperlipidemia, diabetes, and liver cancer. Therefore, it is of great importance to develop an efficient tool for the accurate detection of CEs in living organisms. Herein, an innovative near-infrared (NIR) fluorescent probe, TTAP−AB, was designed for CE detection based on the aggregation-induced emission (AIE) mechanism. This probe exhibits rapid response (2 min), excellent sensitivity (limit of detection = 8.14 × 10−6 U/mL), and high selectivity to CEs. Additionally, owing to its good biocompatibility, the TTAP−AB probe enables the monitoring of dynamic changes in CE levels under drug-induced modulation in living cells and zebrafish. More importantly, the TTAP−AB probe was successfully employed to image liver tumors and assist in tumor resection through the real-time monitoring of CEs, indicating that TTAP−AB is promising to guide liver cancer surgery. Therefore, the TTAP−AB probe can not only enrich the strategies for CE detection in biological systems but also has great potential for some clinical imaging applications, including medical diagnosis, preclinical research, and imaging-guided surgery. [ABSTRACT FROM AUTHOR]

Nanomedicine is a discipline of medicine that applies all aspects of nanotechnology strategies and concepts for treatment and screening possibilities. Synthetic polymer nanostructures are among the many nanomedicine formulations frequently studied for their potential as vectors. Bioimaging is a valuable diagnostic tool, thus, there is always a demand for new excipients/nanocarriers. In this study, hydrophobic hyperbranched poly(lauryl methacrylate) (PLMA) homopolymers comprised of highly hydrophobic LMA moieties with –COOH polar end groups were synthesized by employing reversible addition-fragmentation chain transfer (RAFT) polymerization. Ethylene glycol dimethacrylate (EGDMA) was utilized as the branching agent. End groups are incorporated through the RAFT agent utilized. The resulting amphiphilic hyperbranched polymer was molecularly characterized by size exclusion chromatography (SEC), Fourier transformation infrared spectroscopy (FT–IR), and 1H–NMR spectroscopy. Pyrene, curcumin, and IR-1048 dye were hydrophobic payload molecules successfully encapsulated to show how adaptable these homopolymer nanoparticles (prepared by nanoprecipitation in water) are as dye nanocarriers. This study demonstrates a simple way of producing excipients by generating polymeric nanoparticles from an amphiphilic, hyperbranched, hydrophobic homopolymer, with a low fraction of polar end groups, for bioimaging purposes. [ABSTRACT FROM AUTHOR]

Herein, luminous blue carbon quantum dots (CDs) employing Anisomeles indica (Catmint) were reported with imaging, self‐targeting, and therapeutic effects on triple‐negative breast cancer (TNBC, MDA‐MB‐231) cells. The salient features of CDs generated from catmint are as follows: i) optical studies confirm CDs with excitation‐dependent emission; ii) high‐throughput characterization authenticates the formation of CDs with near‐spherical shape with diameter ranging between 5 and 15 nm; iii) CDs induce cytotoxicity (3.22 ± 0.64 μg/ml) in triple‐negative breast cancer (TNBC, MDA‐MB‐231) cells; iv) fluorescence microscopy demonstrates that CDs promote apoptosis by increasing reactive oxygen species (ROS) and decreasing mitochondrial membrane potential; v) CDs significantly up‐regulate pro‐apoptotic gene expression levels such as caspases‐8/9/3. Finally, our work demonstrates that catmint‐derived CDs are prospective nanotheranostics that augment cancer targeting and imaging. [ABSTRACT FROM AUTHOR]

Inorganic persistent phosphors feature great potential for cancer diagnosis due to the long luminescence lifetime, low background scattering, and minimal autofluorescence. With the prominent advantages of near‐infrared light, such as deep penetration, high resolution, low autofluorescence, and tissue absorption, persistent phosphors can be used for deep bioimaging. We focus on highlighting inorganic persistent phosphors, emphasizing the synthesis methods and applications in cancer diagnostics. Typical synthetic methods such as the high‐temperature solid state, thermal decomposition, hydrothermal/solvothermal, and template methods are proposed to obtain small‐size phosphors for biological organisms. The luminescence mechanisms of inorganic persistent phosphors with different excitation are discussed and effective matrixes including galliumate, germanium, aluminate, and fluoride are explored. Finally, the current directions where inorganic persistent phosphors can continue to be optimized and how to further overcome the challenges in cancer diagnosis are summarized. [ABSTRACT FROM AUTHOR]

Luminescent Ag nanoclusters (Ag NCs) are a promising probe material for sensing and bioimaging applications. However, the intrinsic obstacle of poor water stability and photostability greatly restrict their practical application in biological systems. Herein, we report the intracellular hypochlorite (ClO−) detection with amphiphilic copolymer-modified luminescent Ag NCs with good biocompatibility and photostability. The Ag NCs were synthesized by using chemically inert hydrophobic ligands and then modified with an amphiphilic (1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(poly(ethylene glycol))-2000]) (DSPE-PEG-2000) and sodium dodecyl sulfonate (SDS) for phase transfer. It was found that the approach of the removal of organic solvents during the phase transfer has remarkable influences on the properties of the Ag NCs, including their size, luminescence property, and aqueous stability. Furthermore, the silver core of Ag NCs could be oxidatively damaged by ClO−, thereby causing photoluminescence (PL) quenching. The ClO−-induced PL quenching was specific over the other common reactive oxygen species (ROS) as well as some common interferences. Finally, they have been successfully applied as a fluorescent nanoprobe for detecting exogenous and endogenous ClO− in living cells. [ABSTRACT FROM AUTHOR]

Nitroreductase (NTR) is an enzyme expressed at an abnormally high level in solid tumors, which is associated with the hypoxia level in tumors. The establishment of a high-performance and convenient fluorescent platform for the fast monitoring of NTR is of pivotal importance. Herein, a novel host–guest complex was created by encapsulating a fluorescent substrate GP-NTR within a metal–organic capsule Zn-MPB that included a NADH mimic for the detection of hypoxia via responding to nitroreductase (NTR) with fast responsiveness and good fluorescence imaging. Notably, the double-substrate process was streamlined to a single–substrate process by the host–guest supramolecular method in the catalytic process of NTR, which enabled the reaction to be independent of the cofactor NADH supply and shortened the distance between the substrate and the active site of NTR. The increasing fluorescence intensity of Zn-MPB⊃GP-NTR exhibits a linear relationship with NTR concentration and shows a fast response toward NTR in solution in tens of seconds. Zn-MPB⊃GP-NTR also displays high sensitivity to NTR with a low detection limit of 6.4 ng/mL. Cells and in vivo studies have confirmed that Zn-MPB⊃GP-NTR could be successfully applied for the fast imaging of NTR in NTR-overexpressed tumor cells and tumor-bearing animals. The host–guest platform not only provides a new avenue for the design and optimization of a fluorescence detection platform for the rapid and quantitative detection of NTR activity, but also offers an imaging tool for the early diagnosis of hypoxia-related tumors. [ABSTRACT FROM AUTHOR]

Luminescence imaging in the second near-infrared (NIR-II) window, particularly within the NIR-IIb (1500–1700 nm) sub-window, has been utilized for both fundamental research and clinical applications due to its exceptional spatiotemporal resolution. Nevertheless, efficient contrast agents designed for NIR-IIb imaging are still scarce. Herein, a multilayered rare-earth nanocrystal (NaYF 4 :Yb,Er,Ce@NaYF 4 :Yb,Nd@NaYF 4) with strong NIR-IIb luminescence was designed and synthesized. The doping of Ce3+ ions in the core effectively suppresses the upconversion and boosts the downconversion luminescence by populating the Er 4I 13/2 level. Additionally, by separating the sensitizer (Nd3+) and the activator (Er3+) in different layers, we are able to maximize the light absorption around 800 nm and reduce the cross relaxations between rare-earth elements, which leads to a strong downconversion emission around 1530 nm under 808 nm excitation. After passivation with NaYF 4 shell and phase transfer with highly PEGylated mesoporous silica layer, the nanocomposites with excellent colloidal stability and bright NIR-IIb emission were obtained. With long blood circulation time in vivo, the fabricated nanocomposites enable high resolution and contrast luminescence imaging of the blood vessels and tumors in living mice. Moreover, the rare-earth nanocrystals with superior optical properties also hold great promise for various applications in optical sensing and biomedical imaging. [Display omitted] [ABSTRACT FROM AUTHOR]

Bioluminescence, the light produced by biochemical reactions involving luciferases in living organisms, has been extensively investigated for various applications. It has attracted particular interest as an internal light source for theranostic applications due to its safe and efficient characteristics that overcome the limited penetration of conventional external light sources. Recent advancements in protein engineering technologies and protein delivery platforms have expanded the application of bioluminescence to a wide range of theranostic areas, including bioimaging, biosensing, photodynamic therapy, and optogenetics. This comprehensive review presents the fundamental concepts of bioluminescence and explores its recent applications across diverse fields. Moreover, it discusses future research directions based on the current status of bioluminescent systems for further expansion of their potential. [ABSTRACT FROM AUTHOR]

The newly synthesized chiral active [5]helicene‐like tetrabenzofluorene (TBF) based highly red‐emitting molecules exhibit flower‐like self‐assembly. These molecules display photophysical and structural properties such as intramolecular charge transfer, dual state emission, large fluorescence quantum yield, and solvatochromism. In TBFID, the indandione functional group attached on both sides as the terminal group offers an A‐D‐A push‐pull effect and acts as a strong acceptor to cause more redshift in solution as well as in solid state as compared to TBFPA (TBF with benzaldehyde functional group in terminal position). The self‐assembly studies of TBFID demonstrate the aggregation‐induced emission enhancement (AIEE) attributed to the restriction of intramolecular rotation at the aggregated state. Furthermore, TBFID shows high quantum yield and intense red emission, making the molecule fit for organic light‐emitting diodes (OLED) and bioimaging applications. [ABSTRACT FROM AUTHOR]

Gold nanoclusters (AuNCs) are a class of novel luminescent nanomaterials that exhibit unique properties of ultra-small size, featuring strong anti-photo-bleaching ability, substantial Stokes shift, good biocompatibility, and low toxicity. Various biomolecules have been developed as templates or ligands to protect AuNCs with enhanced stability and luminescent properties for biomedical applications. In this review, the synthesis of AuNCs based on biomolecules including amino acids, peptides, proteins and DNA are summarized. Owing to the advantages of biomolecule-protected AuNCs, they have been employed extensively for diverse applications. The biological applications, particularly in bioimaging, biosensing, disease therapy and biocatalysis have been described in detail herein. Finally, current challenges and future potential prospects of bio-templated AuNCs in biological research are briefly discussed. [ABSTRACT FROM AUTHOR]

Photoluminescent materials (PLNs) are photoluminescent materials that can absorb external excitation light, store it, and slowly release it in the form of light in the dark to achieve long-term luminescence. Developing near-infrared (NIR) PLNs is critical to improving long-afterglow luminescent materials. Because they excite in vitro, NIR-PLNs have the potential to avoid interference from in vivo autofluorescence in biomedical applications. These materials are promising for biosensing and bioimaging applications by exploiting the near-infrared biological window. First, we discuss the biomedical applications of PLNs in the first near-infrared window (NIR-I, 700–900 nm), which have been widely developed and specifically introduce biosensors and imaging reagents. However, the light in this area still suffers from significant light scattering and tissue autofluorescence, which will affect the imaging quality. Over time, fluorescence imaging technology in the second near-infrared window (NIR-II, 1000–1700 nm) has also begun to develop rapidly. NIR-II fluorescence imaging has the advantages of low light scattering loss, high tissue penetration depth, high imaging resolution, and high signal-to-noise ratio, and it shows broad application prospects in biological analysis and medical diagnosis. This critical review collected and sorted articles from the past 5 years and introduced their respective fluorescence imaging technologies and backgrounds based on the definitions of NIR-I and NIR-II. We also analyzed the current advantages and dilemmas that remain to be solved. Herein, we also suggested specific approaches NIR-PLNs can use to improve the quality and be more applicable in cancer research. [ABSTRACT FROM AUTHOR]

Optical bioimaging is an ever‐growing field that benefits both from the fast progress of optical instrumentation and modalities, and from the development of light‐emitting probes. The efficacy of molecular fluorescent dyes is crucial, yet hindered by limited brightness and hydrophilicity. Addressing these challenges, self‐stabilized fluorogenic organic nanoparticles only made of pure dyes (dFONs) are introduced in this work. Comprising thiol‐sensitive fluorogenic chromophores, these dFONs exhibit enhanced brightness exclusively in the presence of biological thiols, notably glutathione, overcoming the need for water‐solubilizing moieties. Importantly, these nanoparticles demonstrate large fluorescence and one‐ and two‐photon brightness, enabling sensitive bioimaging of intracellular thiols at micromolar concentrations. Notably, only the pristine fluorogenic nanoparticles can penetrate the cells and does not require to wash the cells before imaging, emphasizing their unique role as dye carriers, fluorogenic probes and ease of use. This work highlights the transformative potential of dFONs in advancing optical bioimaging, paving the way for the use of dFONs not just as tracers, but also now as biosensors and ultimately in the future as biomarkers. [ABSTRACT FROM AUTHOR]

Since their emergence in 2014, graphitic carbon nitride quantum dots (g‐C3N4 QDs) have attracted much interest from the scientific community due to their distinctive physicochemical features, including structural, morphological, electrochemical, and optoelectronic properties. Owing to their desirable characteristics, such as non‐zero band gap, ability to be chemically functionalized or doped, possessing tunable properties, outstanding dispersibility in different media, and biocompatibility, g‐C3N4 QDs have shown promise for photocatalysis, energy devices, sensing, bioimaging, solar cells, optoelectronics, among other applications. As these fields are rapidly evolving, it is very strenuous to pinpoint the emerging challenges of the g‐C3N4 QDs development and application during the last decade, mainly due to the lack of critical reviews of the innovations in the g‐C3N4 QDs synthesis pathways and domains of application. Herein, an extensive survey is conducted on the g‐C3N4 QDs synthesis, characterization, and applications. Scenarios for the future development of g‐C3N4 QDs and their potential applications are highlighted and discussed in detail. The provided critical section suggests a myriad of opportunities for g‐C3N4 QDs, especially for their synthesis and functionalization, where a combination of eco‐friendly/single step synthesis and chemical modification may be used to prepare g‐C3N4 QDs with, for example, enhanced photoluminescence and production yields. [ABSTRACT FROM AUTHOR]

Images are at the core of most modern biological experiments and are used as a major source of quantitative information. Numerous algorithms are available to process images and make them more amenable to be measured. Yet the nature of the quantitative output that is useful for a given biological experiment is uniquely dependent upon the question being investigated. Here, we discuss the 3 main types of information that can be extracted from microscopy data: intensity, morphology, and object counts or categorical labels. For each, we describe where they come from, how they can be measured, and what may affect the relevance of these measurements in downstream data analysis. Acknowledging that what makes a measurement 'good' is ultimately down to the biological question being investigated, this review aims at providing readers with a toolkit to challenge how they quantify their own data and be critical of conclusions drawn from quantitative bioimage analysis experiments. [ABSTRACT FROM AUTHOR]

Hypochlorite (ClO-) and viscosity both affect the physiological state of mitochondria, and their abnormal levels are closely related to many common diseases. Therefore, it is vitally important to develop mitochondria-targeting fluorescent probes for the dual sensing of ClO- and viscosity. Herein, we have explored a new fluorescent probe, XTAP-Bn, which responds sensitively to ClO- and viscosity with off-on fluorescence changes at 558 and 765 nm, respectively. Because the emission wavelength gap is more than 200 nm, XTAP-Bn can effectively eliminate the signal crosstalk during the simultaneous detection of ClO- and viscosity. In addition, XTAP-Bn has several advantages, including high selectivity, rapid response, good water solubility, low cytotoxicity, and excellent mitochondrial-targeting ability. More importantly, probe XTAP-Bn is successfully employed to monitor the dynamic change in ClO- and viscosity levels in the mitochondria of living cells and zebrafish. This study not only provides a reliable tool for identifying mitochondrial dysfunction but also offers a potential approach for the early diagnosis of mitochondrial-related diseases. [ABSTRACT FROM AUTHOR]

A growing antimicrobial crisis has increased demand for antimicrobial materials. It has become increasingly popular to convert polymeric macromolecules into polymeric carbon particles (PCP) in order to achieve highly biocompatible materials with unique properties as a result of the ability to synthesize nanomaterials of the right size and add value to existing stable polymers. This work presents the tuning of PCP for antibacterial application by combining a biocidal polymer with one‐pot solvothermal synthesis. PCP displayed broad‐spectrum antibacterial activity via various mechanisms, including inhibition of bacterial cell walls, ROS generation, and antibiotic resistance. Furthermore, these biocidal PCP were observed to show excitation‐independent near‐white light emission which on the other hand is generally possible due to mixed sizes, doping, and surface effects. As opposed to the parent biocidal polymer, PCP added ROS‐mediated bactericidal activity, increased cytocompatibility, and nanofibers with anti‐adhesive effects and potential of imaging bacterial cells. [ABSTRACT FROM AUTHOR]

Mitochondria play a crucial role in mediating apoptosis and have emerged as a promising therapeutic target for the treatment of cancer. Nevertheless, exploration of mitochondrial apoptosis as a mechanism for anticancer activity in vitro remains notably sparse. Herein, the ligands 4′,4″′‐(phenylazanediyl)bis(([1,1′‐biphenyl]‐4‐carboxylic acid)) (H2L1) and 4′,4″′‐(phenylazanediyl)bis(3‐fluoro‐[1,1′‐biphenyl]‐4‐carboxylic acid) (H2L2) were synthesized and further combined with organotin precursors and auxiliary ligands (4,4′‐bipy = 4,4′‐bipyridine, 4,4′‐bpe = 4,4′‐vinylenedipyridine) to give eight organotin complexes [(Ph3Sn)2L] (1a and 2a), [(Et3Sn)2L]n (1b and 2b), [(n‐Bu3Sn)2L(4,4′‐bipy)]n (1c and 2c), [(n‐Bu3Sn)2L(4,4′‐bpec)]n (1d and 2d). The complexes were characterized by X‐ray single crystal diffraction, NMR (1H, 13C, and 119Sn), IR, and UV–Vis spectroscopy. The complexes exhibited strong anticancer activity against the four cancer cells and a certain degree of broad‐spectrum with the IC50 ranging from 0.25 to 22.43 μM. Furthermore, complexes 2a and 2b were selected as representatives to further investigate their anticancer mechanisms. The results suggested that these complexes could target mitochondria after cellular uptake, thereby inducing intracellular ROS production, leading to MMP collapse and activation of caspase‐3, that is, these complexes potentially exert their anticancer effects through the mitochondria‐mediated apoptotic pathway. [ABSTRACT FROM AUTHOR]

As a vital biological molecule, H2O2(Hydrogen Peroxide) is involved in different physiological and pathological processes. And in addition to this, H2O2 is suitable for medical wound disinfection, environmental disinfection and food disinfection. Accordingly, it is of high significance to conveniently and effectively detect H2O2 in the environment and organisms. This subject synthesised a fluorescent probe Pyrimidine-Se by using selenomorpholine and pyrimidine dye, which detect H2O2 in an aqueous environment. Pyrimidine-Se has a large Stokes shift (Δλ = 155 nm), which can specifically and quickly quantitatively detect H2O2. When the probe Pyrimidine-Se reacted with H2O2, the Se(II) in the selenomorpholine was oxidised to Se(IV), so the electron withdrawing ability of the electron withdrawing group of Pyrimidine-Se was improved, and the fluorescence intensity of the probe were enhanced. Interestingly, Se(IV) can be reduced by GSH (Glutathione) to Se(II) to quench the fluorescence, and this redox cycle can continue several times, which indicated that it can have a potential of real-time monitoring the redox state in vivo. The probe was also satisfactorily used to detect H2O2 in Argentina Bloodfin larvaes and abnormal H2O2 content in some organs was detected. [ABSTRACT FROM AUTHOR]

Herein, a novel fluorescence probe Fla-DNP based on flavonol has been designed and synthesized for rapid, specific detection of H2S. With the addition of H2S, Fla-DNP triggered thiolysis and released Fla displaying the "turn-on" fluorescence response at 566 nm, which is consistent with the reaction site predicted by calculating Electrostatic potential and ADCH charges. As an easily available H2S probe, Fla-DNP has the advantages of high selectivity, anti-interference, low detection limit (0.834 μM), short response time (6 min), and large Stokes shift (124 nm). The sensing mechanism of H2S was determined by HRMS analysis and DFT calculation. Moreover, Fla-DNP processes a wide range of multiple applications, including the detection of H2S in environmental water samples with good recovery rates ranging from 89.6% to 102.0%, as well as tracking the production of H2S during food spoilage. Meanwhile, the probe exhibits superior biocompatibility and can not only be available used for H2S detection in living cells but be further designed as an H2S-activated CO photoreleaser, based on which it can be developed as a targeted anti-cancer drug. A novel fluorescence probe Fla-DNP was synthesized utilizing 4-dimethylaminobenzoxanthone fluorescent dye (Fla) as the fluorophore, 2, 4-dinitrobenzenether group (DNP) as the recognition group, which can rapidly respond to H2S with high selectivity, anti-interference, low detection limit (0.834 μM), short response time (6 min), and large Stokes shift (124 nm) characteristics. The practical applications of Fla-DNP were further explored in water, foodstuffs samples and living cells. It is reflected that Fla-DNP can not only track H2S in complex environment water, but also can detect H2S produced during foodstuffs spoilage to monitor food freshness. More importantly, Fla-DNP can be available used for H2S detection in living cells and utilize the properties of the photoinduced release of CO from flavonols to be designed as a bifunctional platform for H2S detection and CO release. It is demonstrated that H2S-activated CO photoreleaser Fla-DNP has promise for development as an anti-cancer drug. [ABSTRACT FROM AUTHOR]

Visualization of the spatiotemporal organization and dynamics of the genome in the nucleus is essential to elucidate how chromatin structure and nuclear function are intertwined. In the past, such studies were limited by the lack of appropriate tools. However, various imaging techniques now allow direct visualization of genomic loci in living cells. One of the main drivers behind this progress is the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated proteins (Cas) technology. Initially used as an efficient and specific genome editing tool, the versatility of the CRISPR/Cas system has rapidly expanded its application range to include diagnostics, therapeutics, and, more recently, live cell imaging. In contrast to traditional fluorescent in situ hybridization, CRISPR/Cas-based imaging systems enable real-time dynamic tracking of genomic sequences down to the level of single cells and even a single locus. Recognizing the vital role played by CRISPR/Cas-based imaging systems in advancing our understanding of genome function in relation to its spatiotemporal organization, this review aimed to depict the current landscape of CRISPR/Cas-based technologies in genomic imaging. It discusses the principles, notable features, advantages, and limitations of these CRISPR/Cas-based imaging systems and concludes with a brief outlook into the future. [ABSTRACT FROM AUTHOR]

With the increasing emphasis on ecological safety and physical health, the detection and treatment of harmful substances and diseases are becoming more and more prevalent. Therefore, efficiently monitoring these biological behaviors with high accuracy and sensitivity in real-time has shown prominent research significance. The use of fluorescent probes to analyze organisms has gained momentum in recent years, especially in the field of organ imaging and assisted cancer therapy, where fluorescent bioanalysis demonstrates significant advantageous. In this review, we explored the latest advancements in fluorescent molecular probes (e.g., small-molecule, macro-molecule, supramolecule) and fluorescent nanoparticle probes (e.g., quantum dots or nanoclusters, metal-organic frameworks, polymers, complexes) used as bioanalytical tools in various assays over the last three years. We also delved into their detective mechanisms, specific application areas, and characterization tools for responsive behavior. This review aims to showcase the most recent and comprehensive research progress in fluorescent bioanalysis based on molecular and nanoparticle probes, offering guidance for future developments in the design and fabrication of fluorescent probes and their potential applications. [ABSTRACT FROM AUTHOR]

Advantages like biocompatibility, biodegradability and tunability allowed the exploitation of peptides and peptidomimetics as versatile therapeutic or diagnostic agents. Because of their selectivity towards transmembrane receptors or cell membranes, peptides have also been identified as suitable molecules able to deliver in vivo macromolecules, proteins or nucleic acids. However, after the identification of the homodimer diphenylalanine (FF) as an aggregative motif inside the Aβ1–42 polypeptide, short and ultrashort peptides have been studied as building blocks for the fabrication of supramolecular, ordered nanostructures for applications in biotechnological, biomedical and industrial fields. In this perspective, many hybrid molecules that combine FF with other chemical entities have been synthesized and characterized. Two novel hybrid derivatives (tFaF and cFgF), in which the FF homodimer is alternated with the peptide‐nucleic acid (PNA) heterodimer "g‐c" (guanine‐cytosine) or "a‐t" (adenine‐thymine) and their dimeric forms (tFaF)2 and (cFgF)2 were synthesized. The structural characterization performed by circular dichroism (CD), Fourier transform infrared (FTIR) and fluorescence spectroscopies highlighted the capability of all the FF‐PNA derivatives to self‐assemble into β‐sheet structures. As a consequence of this supramolecular organization, the resulting aggregates also exhibit optoelectronic properties already reported for other similar nanostructures. This photoemissive behavior is promising for their potential applications in bioimaging. [ABSTRACT FROM AUTHOR]

Two-directional beam-tracking (2DBT) is a method for phase-contrast imaging and tomography that uses an intensity modulator to structure the X-ray beam into an array of independent circular beamlets that are resolved by a high-resolution detector. It features isotropic spatial resolution, provides two-dimensional phase sensitivity, and enables the three-dimensional reconstructions of the refractive index decrement, δ, and the attenuation coefficient, μ. In this work, the angular sensitivity and the spatial resolution of 2DBT images in a synchrotron-based implementation is reported. In its best configuration, angular sensitivities of ∼20 nrad and spatial resolution of at least 6.25 µm in phase-contrast images were obtained. Exemplar application to the three-dimensional imaging of soft tissue samples, including a mouse liver and a decellularized porcine dermis, is also demonstrated.

Abstract Recent advancements in cancer research have led to the generation of innovative nanomaterials for improved diagnostic and therapeutic strategies. Despite the proven potential of two-dimensional (2D) molybdenum disulfide (MoS2) as a versatile platform in biomedical applications, few review articles have focused on MoS2-based platforms for cancer theranostics. This review aims to fill this gap by providing a comprehensive overview of the latest developments in 2D MoS2 cancer theranostics and emerging strategies in this field. This review highlights the potential applications of 2D MoS2 in single-model imaging and therapy, including fluorescence imaging, photoacoustic imaging, photothermal therapy, and catalytic therapy. This review further classifies the potential of 2D MoS2 in multimodal imaging for diagnostic and synergistic theranostic platforms. In particular, this review underscores the progress of 2D MoS2 as an integrated drug delivery system, covering a broad spectrum of therapeutic strategies from chemotherapy and gene therapy to immunotherapy and photodynamic therapy. Finally, this review discusses the current challenges and future perspectives in meeting the diverse demands of advanced cancer diagnostic and theranostic applications. Graphical Abstract

Light has profoundly impacted modern medicine and healthcare, with numerous luminescent agents and imaging techniques currently being used to assess health and treat diseases. As an emerging concept in luminescence, aggregation-induced emission (AIE) has shown great potential in biological applications due to its advantages in terms of brightness, biocompatibility, photostability, and positive correlation with concentration. This review provides a comprehensive summary of AIE luminogens applied in imaging of biological structure and dynamic physiological processes, disease diagnosis and treatment, and detection and monitoring of specific analytes, followed by representative works. Discussions on critical issues and perspectives on future directions are also included. This review aims to stimulate the interest of researchers from different fields, including chemistry, biology, materials science, medicine, etc., thus promoting the development of AIE in the fields of life and health.

ABSTRACTThe RNA molecule plays a pivotal role in many biological processes by relaying genetic information, regulating gene expression, and serving as molecular machines and catalyzers. This inherent versatility of RNA has fueled significant advancements in the field of RNA nanotechnology, driving the engineering of complex nanoscale architectures toward biomedical applications, including targeted drug delivery and bioimaging. RNA polymers, serving as building blocks, offer programmability and predictability of Watson-Crick base pairing, as well as non-canonical base pairing, for the construction of nanostructures with high precision and stoichiometry. Leveraging the ease of chemical modifications to protect the RNA from degradation, researchers have developed highly functional and biocompatible RNA architectures and integrated them into preclinical studies for the delivery of payloads and imaging agents. This review offers an educational introduction to the use of RNA as a biopolymer in the design of multifunctional nanostructures applied to targeted delivery in vivo, summarizing physical and biological barriers along with strategies to overcome them. Furthermore, we highlight the most recent progress in the development of both small and larger RNA nanostructures, with a particular focus on imaging reagents and targeted cancer therapeutics in pre-clinical models and provide insights into the prospects of this rapidly evolving field.

Nanotechnology is an advancing field of science with the potential to improve the quality of life through its applications in the field of nanomedicine. It refers to the technology of precisely manipulating atoms and molecules and developing new materials with nanoscale dimensions. Nanoparticles (NPs) typically range in size from 1-100 nm. Nanoparticles play a major role in the prevention of infections, so they can be utilised as nanocarriers with antimicrobial therapeutic actions. This article is a literature review on different methods of synthesis, properties, and biomedical applications of Titanium Dioxide (TiO2) and Zinc oxide (ZnO) nanoparticles. Since nanoparticles can be biomodified by cost-effective methods, the use and applications of NPs will increase in the future. The unique properties of nanoparticles make them useful in various fields of science such as materials, engineering, electronics, food science, and biomedicine. Due to their advantages, nanotechnology has gained the attention of researchers, especially for its promising applications in the healthcare system for better diagnosis and treatment.

Abstract Monoamine oxidases (MAOs) are a class of flavin enzymes that are mainly present in the outer membrane of mitochondria and play a crucial role in maintaining the homeostasis of monoamine neurotransmitters in the central nervous system. Furthermore, expression of MAOs is associated with the functions of peripheral organs. Dysfunction of MAOs is relevant in a variety of diseases such as neurodegenerative diseases, heart failure, metabolic disorders, and cancers. Monoamine oxidases have two isoenzymes, namely, monoamine oxidase A (MAO‐A) and monoamine oxidase B (MAO‐B). Therefore, the development of reliable and specific methods to detect these two isoenzymes is of great significance for the in‐depth understanding of their functions in biological systems, and for further promoting the clinical diagnosis and treatment of MAO‐related diseases. This review mainly focuses on the advances in small molecular probes for the specific imaging of MAO‐A and MAO‐B, including radiolabeled probes, fluorescent probes, and a 19F magnetic resonance imaging probe. In addition, applications of these probes for detecting MAO expression levels in cells, tissues, animal models, and patients are described. Finally, the challenges and perspectives of developing novel MAO imaging probes are also highlighted.