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Abstract Cardiac‐cerebral vascular diseases (CCVDs) are acknowledged as a major threat to public health, leading to more than one‐third of all deaths worldwide. The complex anatomical structure and immune features of blood vessels significantly affect the development of CCVDs, and magnetic resonance angiography (MRA) is one of the main diagnostic approaches for the accurate diagnosis and prognosis of CCVDs. However, MRA suffers from intrinsic problems derived from its blood flow‐dependency, and the clinical Gd‐chelating contrast agents are limited by their rapid vascular extravasation. Over the past decade, spurred on by nanoscience and nanotechnology, numerous contrast agents based on magnetic nanomaterials have been developed to enhance the contrast of MRA, with these including iron oxide nanoparticles, rare earth‐doped nanoparticles, and metal‐organic coordination polymers. The molecular MR imaging of vasculopathy using specific nanoprobes has been explored to obtain a better understanding of the molecular aspects of CCVDs. In this review, the state of the art in MRA nanoprobes is introduced, and recent achievements in the diagnosis of CCVDs using MR imaging are summarized. Additionally, the future prospects and limitations of MRA based on nanoprobes are discussed. The current review provides methodological designs and ideas for subsequent MRA nanoprobes.

Abstract Efficient thrombolysis in time is crucial for prognostic improvement of patients with acute arterial thromboembolic disease, while limitations and complications still exist in conventional thrombolytic treatment methods. Herein, our study sought to investigate a novel dual-mode strategy that integrated ultrasound (US) and near-infrared light (NIR) with establishment of hollow mesoporous silica nanoprobe (HMSN) which contains Arginine-glycine-aspartate (RGD) peptide (thrombus targeting), perfluoropentane (PFP) (thrombolysis with phase-change and stable cavitation) and indocyanine green (ICG) (thrombolysis with photothermal conversion). HMSN is used as the carrier, the surface is coupled with targeted RGD to achieve high targeting and permeability of thrombus, PFP and ICG are loaded to achieve the collaborative diagnosis and treatment of thrombus by US and NIR, so as to provide a new strategy for the integration of diagnosis and treatment of arterial thrombus. From the in vitro and in vivo evaluation, RGD/ICG/PFP@HMSN can aggregate and penetrate at the site of thrombus, and finally establish the dual-mode directional development and thrombolytic treatment under the synergistic effect of US and NIR, providing strong technical support for the accurate diagnosis and treatment of arterial thrombosis. Graphical Abstract

Efficient thrombolysis in time is crucial for prognostic improvement of patients with acute arterial thromboembolic disease, while limitations and complications still exist in conventional thrombolytic treatment methods. Herein, our study sought to investigate a novel dual-mode strategy that integrated ultrasound (US) and near-infrared light (NIR) with establishment of hollow mesoporous silica nanoprobe (HMSN) which contains Arginine-glycine-aspartate (RGD) peptide (thrombus targeting), perfluoropentane (PFP) (thrombolysis with phase-change and stable cavitation) and indocyanine green (ICG) (thrombolysis with photothermal conversion). HMSN is used as the carrier, the surface is coupled with targeted RGD to achieve high targeting and permeability of thrombus, PFP and ICG are loaded to achieve the collaborative diagnosis and treatment of thrombus by US and NIR, so as to provide a new strategy for the integration of diagnosis and treatment of arterial thrombus. From the in vitro and in vivo evaluation, RGD/ICG/PFP@HMSN can aggregate and penetrate at the site of thrombus, and finally establish the dual-mode directional development and thrombolytic treatment under the synergistic effect of US and NIR, providing strong technical support for the accurate diagnosis and treatment of arterial thrombosis. [ABSTRACT FROM AUTHOR]

Vancomycin is employed to treat infections caused by gram-positive bacteria. Ensuring precise vancomycin dosages is essential to avoid the emergence of bacterial resistance. In the current study, a fluorescent nanoprobe was designed for vancomycin determination in exhaled breath condensate samples. The nanoprobe was based on carbon dots (CDs) doped with nitrogen, sulfur, phosphorus, and chlorine (NSPCl-doped CDs). Vancomycin significantly reduced the fluorescence of NSPCl-doped CDs and presented a quenching process in the analytical response of the probe within a concentration range of 0.01–2.0 μg mL−1 due to forming a non-fluorescent complex. The nanoprobe's intra-day and inter-day relative standard deviations were 1.4 % and 3.2 %, respectively. This nanoprobe was successfully used to determine vancomycin in the patients receiving this drug collected from the expiratory circuit of the mechanical ventilator.

Abstract Background Mesothelin (MSLN) has been implicated in cancer migration, invasion, and prognosis, making it a potential tumor marker. However, the precise role of MSLN in the migration and invasion of malignant pleural mesothelioma (MPM) remains elusive, and effective noninvasive methods for assessing MSLN status are currently lacking. In this study, we focused on MSLN expression and elucidated the underlying mechanisms by which MSLN regulates migration and invasion in MPM. Building upon this knowledge, we developed an MRI nanoprobe that targets MSLN to assess its status in vitro and in vivo by comparing T2 signal intensity and T2 values on magnetic resonance imaging examinations. This nanoprobe combines the anatomical information obtained from MRI with biological information obtained from MSLN for comprehensive evaluation of MPM. Results Notably, we observed that MSLN expression in the epithelial type of MPM was higher and increased continuously with tumor growth than that in other types. In addition, MSLN upregulation promoted N-cadherin, matrix metalloproteinase-7, and MMP9 expression and resulted in higher migration/invasion ability and shorter survival. We synthesized MSLN-targeted nanoprobes (Fe3O4@SiO2-PEG-MSLN, FSPM) to assess MSLN expression by comparing the T2 signal intensity and T2 value of different cell lines and mice after 14, 28, and 42 days of modeling. Remarkably, MSLN-targeted nanoprobes demonstrated excellent targeting capabilities. In vitro studies revealed a pronounced reduction in T2 signal intensity and T2 values of the epithelial type as the probe concentration increased. In addition, in vivo experiments demonstrated a gradual decline in these parameters over time, particularly in the epithelial type as compared to the biphasic type, corresponding to the dynamic expression patterns of MSLN during different growth stages. Conclusion Our comprehensive research succeeded in confirming the regulatory mechanisms by which MSLN influences migration and invasion. Moreover, we introduced a promising method for monitoring MSLN expression that may help in facilitating the early detection, histological subtype identification, and assessment of migration, invasion, and prognosis in MPM.

Abstract The accurate preoperative diagnosis and tracking of lung adenocarcinoma is hindered by non-targeting and diffusion of dyes used for marking tumors. Hence, there is an urgent need to develop a practical nanoprobe for tracing lung adenocarcinoma precisely even treating them noninvasively. Herein, Gold nanoclusters (AuNCs) conjugate with thyroid transcription factor-1 (TTF-1) antibody, then multifunctional nanoprobe Au-TTF-1 is designed and synthesized, which underscores the paramount importance of advancing the machine learning diagnosis and bioimaging-guided treatment of lung adenocarcinoma. Bright fluorescence (FL) and strong CT signal of Au-TTF-1 set the stage for tracking. Furthermore, the high specificity of TTF-1 antibody facilitates selective targeting of lung adenocarcinoma cells as compared to common lung epithelial cells, so machine learning software Lung adenocarcinoma auxiliary detection system was designed, which combined with Au-TTF-1 to assist the intelligent recognition of lung adenocarcinoma jointly. Besides, Au-TTF-1 not only contributes to intuitive and targeted visualization, but also guides the following noninvasive photothermal treatment. The boundaries of tumor are light up by Au-TTF-1 for navigation, it penetrates into tumor and implements noninvasive photothermal treatment, resulting in ablating tumors in vivo locally. Above all, Au-TTF-1 serves as a key platform for target bio-imaging navigation, machine learning diagnosis and synergistic PTT as a single nanoprobe, which demonstrates attractive performance on lung adenocarcinoma. Graphical Abstract

Despite significant advancements in cancer research, real-time monitoring and effective treatment of cancer through non-invasive techniques remain a challenge. Herein, a novel polydopamine (PDA) nucleic acid nanoprobe has been developed for imaging signal amplification of intracellular mRNA and precise photothermal therapy guidance in cancer cells. The PDA nucleic acid nanoprobe (PDA@DNA) is constructed by assembling an aptamer hairpin (H1) labeled with the Cy5 fluorophore and another nucleic acid recognition hairpin (H2) onto PDA nanoparticles (PDA NPs), which have exceptionally high fluorescence quenching ability and excellent photothermal conversion properties. The nanoprobe could facilitate cellular uptake of DNA molecules and their protection from nuclease degradation. Upon recognition and binding to the intracellular mRNA target, a catalytic hairpin assembly (CHA) reaction occurs. The stem of H1 unfolds upon binding, allowing the exposed H1 to hybridize with H2, forming a flat and sturdy DNA double-stranded structure that detaches from the surface of PDA NPs. At the same time, the target mRNA is displaced and engages in a new cyclic reaction, resulting in the recovery and significant amplification of Cy5 fluorescence. Using thymidine kinase1 (TK1) mRNA as a model mRNA, this nanoprobe enables the analysis of TK1 mRNA with a detection limit of 9.34 pM, which is at least two orders of magnitude lower than that of a non-amplifying imaging nucleic acid probe. Moreover, with its outstanding performance for in vitro detection, this nanoprobe excels in precisely imaging tumor cells. Through live-cell TK1 mRNA imaging, it can accurately distinguish between tumor cells and normal cells. Furthermore, when exposed to 808-nm laser irradiation, the nanoprobe fully harnesses exceptional photothermal conversion properties of PDA NPs. This results in a localized temperature increase within tumor cells, which ultimately triggers apoptosis in these tumor cells. The integration of PDA@DNA presents innovative prospects for tumor diagnosis and image-guided tumor therapy, offering the potential for high-precision diagnosis and treatment of tumors. [ABSTRACT FROM AUTHOR]

The accurate preoperative diagnosis and tracking of lung adenocarcinoma is hindered by non-targeting and diffusion of dyes used for marking tumors. Hence, there is an urgent need to develop a practical nanoprobe for tracing lung adenocarcinoma precisely even treating them noninvasively. Herein, Gold nanoclusters (AuNCs) conjugate with thyroid transcription factor-1 (TTF-1) antibody, then multifunctional nanoprobe Au-TTF-1 is designed and synthesized, which underscores the paramount importance of advancing the machine learning diagnosis and bioimaging-guided treatment of lung adenocarcinoma. Bright fluorescence (FL) and strong CT signal of Au-TTF-1 set the stage for tracking. Furthermore, the high specificity of TTF-1 antibody facilitates selective targeting of lung adenocarcinoma cells as compared to common lung epithelial cells, so machine learning software Lung adenocarcinoma auxiliary detection system was designed, which combined with Au-TTF-1 to assist the intelligent recognition of lung adenocarcinoma jointly. Besides, Au-TTF-1 not only contributes to intuitive and targeted visualization, but also guides the following noninvasive photothermal treatment. The boundaries of tumor are light up by Au-TTF-1 for navigation, it penetrates into tumor and implements noninvasive photothermal treatment, resulting in ablating tumors in vivo locally. Above all, Au-TTF-1 serves as a key platform for target bio-imaging navigation, machine learning diagnosis and synergistic PTT as a single nanoprobe, which demonstrates attractive performance on lung adenocarcinoma. [ABSTRACT FROM AUTHOR]

Background: Mesothelin (MSLN) has been implicated in cancer migration, invasion, and prognosis, making it a potential tumor marker. However, the precise role of MSLN in the migration and invasion of malignant pleural mesothelioma (MPM) remains elusive, and effective noninvasive methods for assessing MSLN status are currently lacking. In this study, we focused on MSLN expression and elucidated the underlying mechanisms by which MSLN regulates migration and invasion in MPM. Building upon this knowledge, we developed an MRI nanoprobe that targets MSLN to assess its status in vitro and in vivo by comparing T2 signal intensity and T2 values on magnetic resonance imaging examinations. This nanoprobe combines the anatomical information obtained from MRI with biological information obtained from MSLN for comprehensive evaluation of MPM. Results: Notably, we observed that MSLN expression in the epithelial type of MPM was higher and increased continuously with tumor growth than that in other types. In addition, MSLN upregulation promoted N-cadherin, matrix metalloproteinase-7, and MMP9 expression and resulted in higher migration/invasion ability and shorter survival. We synthesized MSLN-targeted nanoprobes (Fe3O4@SiO2-PEG-MSLN, FSPM) to assess MSLN expression by comparing the T2 signal intensity and T2 value of different cell lines and mice after 14, 28, and 42 days of modeling. Remarkably, MSLN-targeted nanoprobes demonstrated excellent targeting capabilities. In vitro studies revealed a pronounced reduction in T2 signal intensity and T2 values of the epithelial type as the probe concentration increased. In addition, in vivo experiments demonstrated a gradual decline in these parameters over time, particularly in the epithelial type as compared to the biphasic type, corresponding to the dynamic expression patterns of MSLN during different growth stages. Conclusion: Our comprehensive research succeeded in confirming the regulatory mechanisms by which MSLN influences migration and invasion. Moreover, we introduced a promising method for monitoring MSLN expression that may help in facilitating the early detection, histological subtype identification, and assessment of migration, invasion, and prognosis in MPM. [ABSTRACT FROM AUTHOR]

Antibiotic residue and toxic heavy metals in aquaculture have a hazardous impact on human health and environmental safety. So the biggest challenge is designing a powerful detecting tool without harming fisheries and the environment. A novel dual-function silver/graphene quantum dots (Ag@GQDs)-based fluorescence nanosensor was developed to investigate unprecedented sensing strategies for sensitive and selective detection of antibiotics and heavy metals to ensure that they are present in the authorized percentage. Here, the fluorescence nanocomposites achieve a new successful sensitive and rapid detection for Oxytetracycline (OTC) and Erythromycin (ERY) antibiotics with detection limits of 2.714 nM and 3.306 nM, respectively. The proposed strategy provides an efficient detection way of tracing heavy metals Hg, Cd, and Pb with a detection limit of less than 5 ppm. Characterization of nanoprobe was by UV/VIS spectroscopy, X-ray Diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and Transmission electron microscopy (TEM). The compared results were with graphene quantum dots (GQDs), graphene oxide quantum dots (GOQDs), and green synthesized silver nanoparticles (AgNPs) which were made from new extracts of aquatic plants and seaweeds from Edku and Marriott Lake. This novel Fluorescence quenching-based technique is sensitive, selective, less time-consuming and does not need expensive preparations to replace the commonly used chromatographic detecting techniques. [ABSTRACT FROM AUTHOR]

Given that cancer mortality is usually due to a late diagnosis, early detection is crucial to improve the patient's results and prevent cancer-related death. Imaging technology based on novel nanomaterials has attracted much attention for early-stage cancer diagnosis. In this study, a new block copolymer, poly(ethylene glycol)-poly(l-lactide) diblock copolymer (PEG-PLLA), was synthesized by the ring-opening polymerization method and thoroughly characterized using Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectroscopy (H-NMR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The obtained PEG-PLLA was used to prepare nanoparticles encapsulated with perfluoropentane and salicylic acid by the emulsion-solvent evaporation method, resulting in a new dual-mode nano-image probe (PEG-PLLA@SA·PFP). The zeta potential and mean diameter of the obtained nanoparticles were measured using dynamic light scattering (DLS) with a Malvern Zetersizer Nano. The in vitro biocompatibility of the PEG-PLLA nanoparticles was evaluated with cell migration, hemolysis, and cytotoxicity assays. Ultrasonic imaging was performed using an ultrasonic imaging apparatus, and chemical exchange saturation transfer (CEST) MRI was conducted on a 7.0 T animal scanner. The results of IR and NMR confirmed that the PEG-PLLA was successfully synthesized. The particle size and negative charge of the nanoparticles were 223.8 ± 2.5 nm and −39.6 ± 1.9 mV, respectively. The polydispersity of the diameter was 0.153 ± 0.020. These nanoparticles possessed good stability at 4 °C for about one month. The results of cytotoxicity, cell migration, and hemolysis assays showed that the carrier material was biocompatible. Finally, PEG-PLLA nanoparticles were able to significantly enhance the imaging effect of tumors by the irradiation of ultrasound and saturation by a radiofrequency pulse, respectively. In conclusion, these nanoparticles exhibit promising dual-mode capabilities for US/CEST MR imaging. [ABSTRACT FROM AUTHOR]

Although the extraordinary progress has been made in molecular biology, the prevention of cancer remains arduous. Most solid tumours exhibit both spatial and temporal heterogeneity, which is difficult to be mimicked in vitro. Additionally, the complex biochemical and immune features of tumour microenvironment significantly affect the tumour development. Molecular imaging aims at the exploitation of tumour‐associated molecules as specific targets of customized molecular probe, thereby generating image contrast of tumour markers, and offering opportunities to non‐invasively evaluate the pathological characteristics of tumours in vivo. Particularly, there are no "standard markers" as control in clinical imaging diagnosis of individuals, so the tumour pathological characteristics‐responsive nanoprobe‐based quantitative molecular imaging, which is able to visualize and determine the accurate content values of heterogeneous distribution of pathological molecules in solid tumours, can provide criteria for cancer diagnosis. In this context, a variety of "smart" quantitative molecular imaging nanoprobes have been designed, in order to provide feasible approaches to quantitatively visualize the tumour‐associated pathological molecules in vivo. This review summarizes the recent achievements in the designs of these nanoprobes, and highlights the state‐of‐the‐art technologies in quantitative imaging of tumour‐associated pathological molecules. [ABSTRACT FROM AUTHOR]

Fe-based single-atomic site catalysts (SASCs), with the natural metalloproteases-like active site structure, have attracted widespread attention in biocatalysis and biosensing. Precisely, controlling the isolated single-atom Fe-N-C active site structure is crucial to improve the SASCs' performance. In this work, we use a facile ion-imprinting method (IIM) to synthesize isolated Fe-N-C single-atomic site catalysts (IIM-Fe-SASC). With this method, the ion-imprinting process can precisely control ion at the atomic level and form numerous well-defined single-atomic Fe-N-C sites. The IIM-Fe-SASC shows better peroxidase-like activities than that of non-imprinted references. Due to its excellent properties, IIM-Fe-SASC is an ideal nanoprobe used in the colorimetric biosensing of hydrogen peroxide (H2O2). Using IIM-Fe-SASC as the nanoprobe, in situ detection of H2O2 generated from MDA-MB-231 cells has been successfully demonstrated with satisfactory sensitivity and specificity. This work opens a novel and easy route in designing advanced SASC and provides a sensitive tool for intracellular H2O2 detection.

Abstract Although the extraordinary progress has been made in molecular biology, the prevention of cancer remains arduous. Most solid tumours exhibit both spatial and temporal heterogeneity, which is difficult to be mimicked in vitro. Additionally, the complex biochemical and immune features of tumour microenvironment significantly affect the tumour development. Molecular imaging aims at the exploitation of tumour‐associated molecules as specific targets of customized molecular probe, thereby generating image contrast of tumour markers, and offering opportunities to non‐invasively evaluate the pathological characteristics of tumours in vivo. Particularly, there are no “standard markers” as control in clinical imaging diagnosis of individuals, so the tumour pathological characteristics‐responsive nanoprobe‐based quantitative molecular imaging, which is able to visualize and determine the accurate content values of heterogeneous distribution of pathological molecules in solid tumours, can provide criteria for cancer diagnosis. In this context, a variety of “smart” quantitative molecular imaging nanoprobes have been designed, in order to provide feasible approaches to quantitatively visualize the tumour‐associated pathological molecules in vivo. This review summarizes the recent achievements in the designs of these nanoprobes, and highlights the state‐of‐the‐art technologies in quantitative imaging of tumour‐associated pathological molecules.

Ferroptosis is a non-apoptotic cell death regulated by iron-dependent lipid peroxidation. Glutathione (GSH), a key antioxidant against oxidative damage, is involved in one of the most important metabolic pathways of ferroptosis. Herein, an excellent plasmonic nanoprobe was developed for highly sensitive, in situ, dynamic real-time monitoring of intracellular GSH levels during ferroptosis. A nanoprobe was prepared by functionalizing gold nanoparticles (AuNPs) with the probe molecule crystal violet (CV). The fluctuation in the SERS signal intensity of CV via the competitive displacement reaction can be used to detect GSH. The advantages of the plasmonic nanoprobe including low-cost production techniques, outstanding stability and biocompatibility, high specificity and sensitivity towards GSH with a detection limit of 0.05 μM. It enables real-time dynamic monitoring of GSH levels in living cells during erastin-induced ferroptosis. This approach is expected to provide important theoretical support for elucidating the GSH-related ferroptosis metabolic mechanism and advancing our understanding of ferroptosis-based cancer therapy. [ABSTRACT FROM AUTHOR]

Background: Niosomes are primary-bilayer vesicles used in anticancer drugs. The aim of this study is the synthesis of nisome nanocarrier containing Artemisia Annua extract and its anticancer charactersitics. Materials and Methods: This in-vitro study was carried out at the Islamic Azad University, North Tehran Branch, from December 1400 to September 1401. Firstly, a niosomes nanocarrier was synthesized with the thin-layer hydration approach. Then, Artemisia Annua extract was loaded into them. Following that, physical and chemical features of nanocarriers were evaluated utilizing scanning electron microscope (SEM) and dynamic light scattering (DLS). The encapsulation level and the release pattern of the extract were valiadated vi a dialysis bag. Finally, its anticancer effects were investigated on breast cancer cell line (MCF_7). Results: The results showed that the synthesized nanocarrier of nisome containing the extract has a spherical structure and its size was 208.1 nm and the encapsulation percentage was 62.35%. It was also found that the nanocarrier of loaded niosom had significant anticancer effects compared to non-loaded extract. Conclusion: It can be concluded that the nisome-containing Artemisia Annua extract of medicinal plant increases the anti-cancer effects significantly, and therefore, nisome can be used as a targeted drug delivery system for anti-cancer purposes.

Quercetin can help with a variety of health problems. Most methods for measuring quercetin in biological fluids are characterized by low sensitivity and selectivity. The employment of metal–organic frameworks in sensor applications with carbon-based materials ushers in a new era. In this study, blue fluorescent graphene quantum dots (GQDs) embedded in a UiO-66-NH2 metal–organic framework-based nanoprobe (GQDs@UiO-66-NH2) were constructed for quercetin sensing. Initially, maize husk was used to produce blue fluorescent GQDs, whereas zirconium tetrachloride and 2-aminoterephthalic acid were used to synthesize extremely luminous UiO-66-NH2. The addition of quercetin to GQDs@UiO-66-NH2 leads to fluorescence dampening due to the adsorption potential of UiO-66-NH2. The complexation of zirconium ions with the 3-OH and 4-C＝O functionalities of quercetin resulted in fluorescence quenching. The sensor has a linear concentration range and limit of detection for quercetin of 50–500 and 2.82 ng/mL, respectively. The nanoprobe’s usefulness for quercetin detection was then validated by a selectivity investigation in the presence of interfering chemicals. Furthermore, the percentage relative standard deviations were 4.20% and 2.90%, respectively, indicating great stability and repeatability. Fluorescence “Turn-On–Off” nanoprobes provide a simple, quick, sensitive, and selective method for monitoring quercetin.

Ischemic stroke is one of the leading causes of disability and mortality. The collaterals provide an alternative pathway to preserve the ischemic brain tissue, and determine the penumbra range, where the neurons are salvageable. Therefore, accurately monitoring the collaterals and identifying the penumbra are crucial. Herein, a low-immunogenic nanoprobe-based MRI strategy is developed to simultaneously identify the infarct core, collaterals distribution, and ischemic penumbra distributions. The low-immunogenic nanoprobe was constructed by covalently attaching self-peptide on the surface of biocompatible Fe3O4 nanoparticles as a stealth coating. Both in vitro and in vivo experiments clearly revealed that the nanoprobes can effectively avoid capture by macrophages, and exhibited prolonged blood half-life to continuously enhance the contrast of blood vessels in a longer time window in susceptibility-weighted imaging (SWI), which enabled the delineation of the collaterals and ischemic penumbra. More importantly, combined with the diffusion-weighted imaging (DWI), the infarct core, collateral vessels, and the ischemic penumbra range can be identified simultaneously. In this context, the stroke progress including infarct core growth, collateral vessel formation, and penumbra distribution, can be better understood. This nanoprobe-based strategy thus offers a practical route for precise diagnosis of ischemic stroke, which remains a challenge for conventional MRI strategies.

Fluorescence and photoacoustic imaging techniques offer valuable insights into cell- and tissue-level processes. However, these optical imaging modalities are limited by scattering and absorption in tissue, resulting in the low-depth penetration of imaging. Contrast-enhanced imaging in the near-infrared window improves imaging penetration by taking advantage of reduced autofluorescence and scattering effects. Current contrast agents for fluorescence and photoacoustic imaging face several limitations from photostability and targeting specificity, highlighting the need for a novel imaging probe development. This review covers a broad range of near-infrared fluorescent and photoacoustic contrast agents, including organic dyes, polymers, and metallic nanostructures, focusing on their optical properties and applications in cellular and animal imaging. Similarly, we explore encapsulation and functionalization technologies toward building targeted, nanoscale imaging probes. Bioimaging applications such as angiography, tumor imaging, and the tracking of specific cell types are discussed. This review sheds light on recent advancements in fluorescent and photoacoustic nanoprobes in the near-infrared window. It serves as a valuable resource for researchers working in fields of biomedical imaging and nanotechnology, facilitating the development of innovative nanoprobes for improved diagnostic approaches in preclinical healthcare. [ABSTRACT FROM AUTHOR]

Venous thromboembolism ( VTE), including pulmonary embolism ( PE) and deep vein thrombosis (DVT), is considered as one of the most common cardiovascular diseases in the world, causing a huge social and economic burden. Despite the predominant role in the treatment of VTE, anti-thrombotic therapy has an extremely high risk of bleeding due to its association with blood coagulation and hemolysis system. Therefore, strict monitoring should be performed during the disease progression. However, the existing approaches can not fully meet the needs of precision medicine. Molecular imaging can reflect the disease information at the molecular level. Quantitative monitoring on thrombustargeted nanoprobes through imaging approaches can accurately diagnose disease subtypes and provide personalized treatment. This article reviews the research progress of nanomolecular imaging in the diagnosis and treatment of VTE in recent years, which is expected to provide new ideas for the diagnosis and treatment of VTE. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) prepared by green synthesis have a lot of potentials in various fields. Among them, as an antioxidant, antibacterial agent, and nanoprobe for the colorimetric detection of mercury (Hg2+) ions is thought to be the most important. The antibacterial, antioxidant, and colorimetric sensing potential of the greenly produced AgNPs utilizing Piper chaba stem extract are all predicted in this investigation. By using the disc diffusion method, the antibacterial activity of greenly produced AgNPs are assessed, and the findings are measured from the zone of inhibition (ZOI). It is revealed that the Staphylococcus aureus, Micrococcus spp., Escherichia coli, and Pseudomonas aeruginosa bacterial strains are significantly resisted by the greenly produced AgNPs. The antioxidant activity test of AgNPs reveals a considerable impact on free radical scavenging having the inhibitory concentration (IC50) is 1.13 mL (equivalent to 0.45 mg mL−1). Also, with a low limit of detection of 28 ppm, the resulting AgNPs are used as highly selective and economical colorimetric sensors for Hg2+ detection. The study's findings support the hypothesis that Piper chaba stems can serve as a source for the production of AgNPs with high antibacterial and antioxidant activity and usefulness for simple colorimetric readings of Hg2+. [ABSTRACT FROM AUTHOR]

Bioaffinity nanoprobes are a type of biosensor that utilize the specific binding properties of biological molecules, such as antibodies, enzymes, and nucleic acids, for the detection of foodborne pathogens. These probes serve as nanosensors and can provide highly specific and sensitive detection of pathogens in food samples, making them an attractive option for food safety testing. The advantages of bioaffinity nanoprobes include their ability to detect low levels of pathogens, rapid analysis time, and cost-effectiveness. However, limitations include the need for specialized equipment and the potential for cross-reactivity with other biological molecules. Current research efforts focus on optimizing the performance of bioaffinity probes and expanding their application in the food industry. This article discusses relevant analytical methods, such as surface plasmon resonance (SPR) analysis, Fluorescence Resonance Energy Transfer (FRET) measurements, circular dichroism, and flow cytometry, that are used to evaluate the efficacy of bioaffinity nanoprobes. Additionally, it discusses advances in the development and application of biosensors in monitoring foodborne pathogens. [ABSTRACT FROM AUTHOR]

The interaction of a focused X-ray beam with a sample in a scanning probe experiment can provide a variety of information about the interaction volume. In many scanning probe experiments X-ray fluorescence (XRF) is supplemented with measurements of the transmitted or scattered intensity using a pixelated detector. The automated extraction of different signals from an area pixelated detector is described, in particular the methodology for extracting differential phase contrast (DPC) is demonstrated and different processing methods are compared across a range of samples. The phase shift of the transmitted X-ray beam by the sample, extracted from DPC, is also compared with ptychography measurements to provide a qualitative and quantitative comparison. While ptychography produces a superior image, DPC can offer a simple, flexible method for phase contrast imaging which can provide fast results and feedback during an experiment; furthermore, for many science problems, such as registration of XRF in a lighter matrix, DPC can provide sufficient information to meet the experimental aims. As the DPC technique is a quantitative measurement, it can be expanded to spectroscopic studies and a demonstration of DPC for spectro-microscopy measurements is presented. Where ptychography can separate the absorption and phase shifts by the sample, quantitative interpretation of a DPC image or spectro-microscopy signal can only be performed directly when absorption is negligible or where the absorption contribution is known and the contributions can be fitted.

Yijie Lv,1 Junnan Kan,1 Mingfang Luo,2 Changfeng Yang,1 Xunrong Luo,2 Xiaoqian Lin,1 Hao Li,1 Xueming Li,1 Yuping Li,1 Caixia Yang,1 Yan Liu,1 Xianglin Li1 1School of Medical Imaging, Binzhou Medical University, Yantai, Shandong, 264003, People’s Republic of China; 2Department of Radiology, Sichuan Provincial People’s Hospital, Chengdu, Sichuan, 610072, People’s Republic of ChinaCorrespondence: Yan Liu; Xianglin Li, School of Medical Imaging, Binzhou Medical University, Yantai, Shandong, 264003, People’s Republic of China, Tel +86 535 6919135 ; +86 535 6919175, Email liuericyan@hotmail.com; xlli@bzmc.edu.cnIntroduction: Accurate tumor diagnosis is essential to achieve the ideal therapeutic effect. However, it is difficult to accurately diagnose cancer using a single imaging method because of the technical limitations. Multimodal imaging plays an increasingly important role in tumor treatment. Photodynamic therapy (PDT) has received widespread attention in tumor treatment due to its high specificity and controllable photocytotoxicity. Nevertheless, PDT is susceptible to tumor microenvironment (TME) hypoxia, which greatly reduces the therapeutic effect of tumor treatment.Methods: In this study, a novel multifunctional nano-snowflake probe (USPIO@MnO2@Ce6, UMC) for oxygen-enhanced photodynamic therapy was developed. We have fabricated the honeycomb-like MnO2 to co-load chlorin e6 (Ce6, a photosensitizer) and ultrasmall superparamagnetic iron oxide (USPIO, T1-T2 double contrast agent). Under the high H2O2 level of tumor cells, UMC efficiently degraded and triggered the exposure of photosensitizers to the generated oxygen, accelerating the production of reactive oxygen species (ROS) during PDT. Moreover, the resulting USPIO and Mn2+ allow for MR T1-T2 imaging and transformable PAI for multimodal imaging-guided tumor therapy.Results: TEM and UV-vis spectroscopy results showed that nano-snowflake probe (UMC) was successfully synthesized, and the degradation of UMC was due to the pH/ H2O2 responsive properties. In vitro results indicated good uptake of UMC in 4T-1 cells, with maximal accumulation at 4 h. In vitro and in vivo experimental results showed their imaging capability for both T1-T2 MR and PA imaging, providing the potential for multimodal imaging-guided tumor therapy. Compared to the free Ce6, UMC exhibited enhanced treatment efficiency due to the production of O2 with the assistance of 660 nm laser irradiation. In vivo experiments confirmed that UMC achieved oxygenated PDT under MR/PA imaging guidance in tumor-bearing mice and significantly inhibited tumor growth in tumor-bearing mice, exhibiting good biocompatibility and minimal side effects.Conclusion: The multimodal imaging contrast agent (UMC) not only can be used for MR and PA imaging but also has oxygen-enhanced PDT capabilities. These results suggest that UMC may have a good potential for further clinical application in the future.Graphical Abstract: Keywords: photodynamic therapy, oxygen generation, magnetic resonance imaging, photoacoustic imaging, theranostics, nanoprobe

Quercetin can help with a variety of health problems. Most methods for measuring quercetin in biological fluids are characterized by low sensitivity and selectivity. The employment of metal-organic frameworks in sensor applications with carbon-based materials ushers in a new era. In this study, blue fluorescent graphene quantum dots (GQDs) embedded in a UiO-66-NH2 metal-organic framework-based nanoprobe (GQDs@UiO-66-NH2) were constructed for quercetin sensing. Initially, maize husk was used to produce blue fluorescent GQDs, whereas zirconium tetrachloride and 2-aminoterephthalic acid were used to synthesize extremely luminous UiO-66-NH2. The addition of quercetin to GQDs@UiO-66-NH2 leads to fluorescence dampening due to the adsorption potential of UiO-66-NH2. The complexation of zirconium ions with the 3-OH and 4-C=O functionalities of quercetin resulted in fluorescence quenching. The sensor has a linear concentration range and limit of detection for quercetin of 50-500 and 2.82 ng/mL, respectively. The nanoprobe's usefulness for quercetin detection was then validated by a selectivity investigation in the presence of interfering chemicals. Furthermore, the percentage relative standard deviations were 4.20% and 2.90%, respectively, indicating great stability and repeatability. Fluorescence "Turn-On-Off" nanoprobes provide a simple, quick, sensitive, and selective method for monitoring quercetin. [ABSTRACT FROM AUTHOR]

As an emerging hybrid imaging modality, microwave-induced thermoacoustic imaging (MTAI), using microwaves as the excitation source and ultrasonic signals as the information carrier for combining the characteristics of high contrast of electromagnetic imaging and high resolution of ultrasound imaging, has shown broad prospects in biomedical and clinical applications. The imaging contrast depends on the microwave-absorption coefficient of the endogenous imaged tissue and the injected MTAI contrast agents. With systemically introduced functional nanoparticles, MTAI contrast and sensitivity can be further improved, and enables visualization of biological processes in vivo. In recent years, functional nanoparticles for MTAI have been developed to improve the performance and application range of MTAI in biomedical applications. This paper reviews the recent progress of functional nanoparticles for MTAI and their biomedical applications. The challenges and future directions of microwave thermoacoustic imaging with functional nanoparticles in the field of translational medicine are discussed. [ABSTRACT FROM AUTHOR]

Abstract Silver nanoparticles (AgNPs) prepared by green synthesis have a lot of potentials in various fields. Among them, as an antioxidant, antibacterial agent, and nanoprobe for the colorimetric detection of mercury (Hg2+) ions is thought to be the most important. The antibacterial, antioxidant, and colorimetric sensing potential of the greenly produced AgNPs utilizing Piper chaba stem extract are all predicted in this investigation. By using the disc diffusion method, the antibacterial activity of greenly produced AgNPs are assessed, and the findings are measured from the zone of inhibition (ZOI). It is revealed that the Staphylococcus aureus, Micrococcus spp., Escherichia coli, and Pseudomonas aeruginosa bacterial strains are significantly resisted by the greenly produced AgNPs. The antioxidant activity test of AgNPs reveals a considerable impact on free radical scavenging having the inhibitory concentration (IC50) is 1.13 mL (equivalent to 0.45 mg mL−1). Also, with a low limit of detection of 28 ppm, the resulting AgNPs are used as highly selective and economical colorimetric sensors for Hg2+ detection. The study's findings support the hypothesis that Piper chaba stems can serve as a source for the production of AgNPs with high antibacterial and antioxidant activity and usefulness for simple colorimetric readings of Hg2+.

Introduction: Fluorescent visualization of hydrogen peroxide in the tumor microenvironment (TME) is conducive to predicting malignant prognosis after chemotherapy. Two photon microscopy has been employed for in vivo hydrogen peroxide detection owing to its advantages of deep penetration and low phototoxicity.Methods: In this study, a two-photon fluorescent probe (TPFP) was protected by mesoporous silica nanoparticles (MSNs) and masked by cloaking the cancer cell membranes (CM), forming a tumor-targeted bioactive nanoprobe, termed MSN@TPFP@CM.Results: This multifunctional nanoprobe allowed for the effective and selective detection of excessive hydrogen peroxide production in chemotherapeutic Etoposide (VP-16)-challenged tumor cells using two-photon microscopy. After specific accumulation in tumors, VP-16-MSN@TPFP@CM monitored tumor-specific hydrogen peroxide levels and revealed a positive correlation between oxidative stress in the TME and chemotherapy-exacerbated malignant prognosis.Discussion: Given the recent translation of fluorescent imaging into early clinical trials and the high biocompatibility of bioactive nanoprobes, our approach may pave the way for specific imaging of oxidative stress in solid tumors after treatment and provide a promising technology for malignant prognosis predictions.

As an emerging hybrid imaging modality, microwave-induced thermoacoustic imaging (MTAI), using microwaves as the excitation source and ultrasonic signals as the information carrier for combining the characteristics of high contrast of electromagnetic imaging and high resolution of ultrasound imaging, has shown broad prospects in biomedical and clinical applications. The imaging contrast depends on the microwave-absorption coefficient of the endogenous imaged tissue and the injected MTAI contrast agents. With systemically introduced functional nanoparticles, MTAI contrast and sensitivity can be further improved, and enables visualization of biological processes in vivo. In recent years, functional nanoparticles for MTAI have been developed to improve the performance and application range of MTAI in biomedical applications. This paper reviews the recent progress of functional nanoparticles for MTAI and their biomedical applications. The challenges and future directions of microwave thermoacoustic imaging with functional nanoparticles in the field of translational medicine are discussed.

Quantum dots are the serendipitous outcome of materials research. It is the tiny carbonaceous nanoparticles with diameters ranging from 1 to 10 nm. This review is a brief discussion of the synthesis, properties, and biomedical applicability of quantum dots, especially in herbal therapy. As quantum dots are highly polar, they can be surface decorated with several kinds of polar functionalities, such as polymeric molecules, small functional molecules, and so on. The review also consists of the basic physical and optical properties of quantum dots and their excitation―dependent properties in the application section. We focus on therapeutics, where quantum dots are used as drugs or imaging probes. Nanoprobes for several diagnostics are quite new in the biomedical research domain. Quantum dot―based nanoprobes are in high demand due to their excellent fluorescence, non-bleaching nature, biocompatibility, anchoring feasibility for several analytes, and fast point―of―care sensibility. Lastly, we also included a discussion on quantum dot―based drug delivery as phytomedicine.

Background: Mesothelin (MSLN) has been implicated in cancer migration, invasion, and prognosis, making it a potential tumor marker. However, the precise role of MSLN in the migration and invasion of malignant pleural mesothelioma (MPM) remains elusive, and effective noninvasive methods for assessing MSLN status are currently lacking. In this study, we focused on MSLN expression and elucidated the underlying mechanisms by which MSLN regulates migration and invasion in MPM. Building upon this knowledge, we developed an MRI nanoprobe that targets MSLN to assess its status in vitro and in vivo by comparing T2 signal intensity and T2 values on magnetic resonance imaging examinations. This nanoprobe combines the anatomical information obtained from MRI with biological information obtained from MSLN for comprehensive evaluation of MPM. Results: Notably, we observed that MSLN expression in the epithelial type of MPM was higher and increased continuously with tumor growth than that in other types. In addition, MSLN upregulation promoted N-cadherin, matrix metalloproteinase-7, and MMP9 expression and resulted in higher migration/invasion ability and shorter survival. We synthesized MSLN-targeted nanoprobes (Fe3O4@SiO2-PEG-MSLN, FSPM) to assess MSLN expression by comparing the T2 signal intensity and T2 value of different cell lines and mice after 14, 28, and 42 days of modeling. Remarkably, MSLN-targeted nanoprobes demonstrated excellent targeting capabilities. In vitro studies revealed a pronounced reduction in T2 signal intensity and T2 values of the epithelial type as the probe concentration increased. In addition, in vivo experiments demonstrated a gradual decline in these parameters over time, particularly in the epithelial type as compared to the biphasic type, corresponding to the dynamic expression patterns of MSLN during different growth stages. Conclusion: Our comprehensive research succeeded in confirming the regulatory mechanisms by which MSLN influences migration and invasion. Moreover, we introduced a promising method for monitoring MSLN expression that may help in facilitating the early detection, histological subtype identification, and assessment of migration, invasion, and prognosis in MPM. [ABSTRACT FROM AUTHOR]

The interaction of a focused X-ray beam with a sample in a scanning probe experiment can provide a variety of information about the interaction volume. In many scanning probe experiments X-ray fluorescence (XRF) is supplemented with measurements of the transmitted or scattered intensity using a pixelated detector. The automated extraction of different signals from an area pixelated detector is described, in particular the methodology for extracting differential phase contrast (DPC) is demonstrated and different processing methods are compared across a range of samples. The phase shift of the transmitted X-ray beam by the sample, extracted from DPC, is also compared with ptychography measurements to provide a qualitative and quantitative comparison. While ptychography produces a superior image, DPC can offer a simple, flexible method for phase contrast imaging which can provide fast results and feedback during an experiment; furthermore, for many science problems, such as registration of XRF in a lighter matrix, DPC can provide sufficient information to meet the experimental aims. As the DPC technique is a quantitative measurement, it can be expanded to spectroscopic studies and a demonstration of DPC for spectro-microscopy measurements is presented. Where ptychography can separate the absorption and phase shifts by the sample, quantitative interpretation of a DPC image or spectro-microscopy signal can only be performed directly when absorption is negligible or where the absorption contribution is known and the contributions can be fitted. [ABSTRACT FROM AUTHOR]

The development of nanomedicine has recently achieved several breakthroughs in the field of cancer treatment; however, biocompatibility and targeted penetration of these nanomaterials remain as limitations, which lead to serious side effects and significantly narrow the scope of their application. The self-assembly of intermediate filaments with arginine–glycine–aspartate (RGD) peptide (RGD-IFP) was triggered by the hydrophobic cationic molecule 7-amino actinomycin D (7-AAD) to synthesize a bifunctional nanoparticle that could serve as a fluorescent imaging probe to visualize tumor treatment. The designed RGD-IFP peptide possessed the ability to encapsulate 7-AAD molecules through the formation of hydrogen bonds and hydrophobic interactions by a one-step method. This fluorescent nanoprobe with RGD peptide could be targeted for delivery into tumor cells and released in acidic environments such as endosomes/lysosomes, ultimately inducing cytotoxicity by arresting tumor cell cycling with inserted DNA. It is noteworthy that the RGD-IFP/7-AAD nanoprobe tail-vein injection approach demonstrated not only high tumor-targeted imaging potential, but also potent antitumor therapeutic effects in vivo. The proposed strategy may be used in peptide-driven bifunctional nanoparticles for precise imaging and cancer therapy.

Given that cancer mortality is usually due to a late diagnosis, early detection is crucial to improve the patient’s results and prevent cancer-related death. Imaging technology based on novel nanomaterials has attracted much attention for early-stage cancer diagnosis. In this study, a new block copolymer, poly(ethylene glycol)-poly(l-lactide) diblock copolymer (PEG-PLLA), was synthesized by the ring-opening polymerization method and thoroughly characterized using Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectroscopy (H-NMR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The obtained PEG-PLLA was used to prepare nanoparticles encapsulated with perfluoropentane and salicylic acid by the emulsion-solvent evaporation method, resulting in a new dual-mode nano-image probe (PEG-PLLA@SA·PFP). The zeta potential and mean diameter of the obtained nanoparticles were measured using dynamic light scattering (DLS) with a Malvern Zetersizer Nano. The in vitro biocompatibility of the PEG-PLLA nanoparticles was evaluated with cell migration, hemolysis, and cytotoxicity assays. Ultrasonic imaging was performed using an ultrasonic imaging apparatus, and chemical exchange saturation transfer (CEST) MRI was conducted on a 7.0 T animal scanner. The results of IR and NMR confirmed that the PEG-PLLA was successfully synthesized. The particle size and negative charge of the nanoparticles were 223.8 ± 2.5 nm and −39.6 ± 1.9 mV, respectively. The polydispersity of the diameter was 0.153 ± 0.020. These nanoparticles possessed good stability at 4 °C for about one month. The results of cytotoxicity, cell migration, and hemolysis assays showed that the carrier material was biocompatible. Finally, PEG-PLLA nanoparticles were able to significantly enhance the imaging effect of tumors by the irradiation of ultrasound and saturation by a radiofrequency pulse, respectively. In conclusion, these nanoparticles exhibit promising dual-mode capabilities for US/CEST MR imaging.

Schematic diagram of the preparation of CON@Au-Probe nanoprobe and the mechanism for target methylated DNA detection. [Display omitted] Covalent-organic framework nanosheets (CONs) have received increasing attention in various fields. However, large-scale and high-yield preparation and flexible functionalization of CONs remain a challenging task. Herein, we designed and fabricated a novel ultrathin (<5 nm) vinyl-functionalized CON in large scale (>80 mg) and high yield (>60 %) via an imine-exchange synthesis strategy. Through post-modification strategy, the vinyl-functionalized CONs were sequentially modified with thiols and Au nanoparticles with high distribution density (mass ratio of CONs to Au was about 4:1) and narrow size distribution (3.5 ± 0.5 nm). The synthesized hybrid nanosheets were employed as material platform to design a novel nanoprobe for ultrasensitive detection towards cancer-associated methylated DNA. Integrating site-specific base oxidation damage strategy and target cyclic amplification effect, the well-designed CONs-based nanoprobe achieved high sensitivity for detecting methylated DNA as low as 10 fM and ultrahigh specificity for distinguishing 0.0001% methylation level. Noteworthy, the nanoprobe was successfully applied to the analysis of DNA methylation in human colon cancer cells, expanding the application scope of CONs and opening a new horizon to develop novel CONs-based nanoprobes. [ABSTRACT FROM AUTHOR]

Rapid and accurate differentiation between live and dead cells is highly desirable for the evaluation of cell viability. Here, we report the application of the orange-emitting sulfur-doped organosilica nanodots (S-OSiNDs) for ultrafast (30 s), ultrasensitive (1 μg/mL), and universal staining of the dead bacterial, fungal, and mammalian cells but not the live ones, which satisfies the requirements of a fluorescent probe that can specifically stain the dead cells. We further verify that the fluorescence distribution range of S-OSiNDs (which are distributed in cytoplasm and nucleus) is much larger than that of the commercial dead/fixed cell/tissue staining dye RedDot2 (which is distributed in the nucleus) in terms of dead mammalian cell staining, indicating that S-OSiNDs possess a better staining effect of dead cells than RedDot2. Overall, S-OSiNDs can be used as a robust fluorescent probe for ultrafast and accurate discrimination between dead and live cells at a single cell level, which may find a variety of applications in the biomedical field. [ABSTRACT FROM AUTHOR]

Shigella as a typical foodborne pathogen has strong survivability in the environment or food, leading to infectious diseases, yet its rapid detection technology with high selectivity and sensitivity remains challenging. In this study, complementary strand modified upconversion nanoparticles (UCNPs) can offer stable yellow-green fluorescence at 500–700 nm excited by a 980 nm laser. Importantly, Shigella aptamer modified gold nanoparticles (GNPs) formed by "Au−S" bond act as a fluorescence resonance energy transfer (FRET) donor and recognition element that can bind specifically to Shigella and significantly quench the fluorescence of complementary strand modified UCNPs. As a result, the fluorescence of our developed nanoprobe increased linearly with the increase in Shigella in a wide range from 1.2 × 102 to 1.2 × 108 CFU/mL and the detection limit was as low as 30 CFU/mL. Moreover, the fabricated upconversion fluorescence nanoprobe can achieve Shigella detection in contaminated chicken without enrichment in 1 h. [ABSTRACT FROM AUTHOR]

Novel anthracene-based Schiff base derivative (4-(anthracen-9-ylmethylene) amino)-5-phenyl-4H-1,2,4-triazole-3-thiol; AT2) is synthesized and utilized as an aggregation-induced emission-enhancement (AIEE) active probe to detect Zn2+ and Tyrosine. Ultraviolet-visible absorption/photoluminescence (UV-vis/PL) spectroscopy studies on the AIEE property of AT2 (in ethanol) with increasing water fractions (fw: 0–97.5%) confirm the J-type aggregation. Excellent sensor selectivity of AT2 to Zn2+ and its reversibility with Tyrosine are demonstrated with PL interrogations. 2:1 and 1:1 stoichiometry and binding sites of AT2-Zn2+ and Tyrosine-Zn2+ complexes are elucidated from Job plots, HR-mass, and 1H-NMR results. Nanomolar-level detection limits (LODs) of Zn2+ (179 nM) and Tyrosine (667 nM) and association constants (Kas) of 2.28 × 10−6 M−2 (for AT2-Zn2+) and 1.39 × 10−7 M−1 (for Tyrosine-Zn2+) are determined from standard deviation and linear fittings. Nanofiber formation in AIEE and aggregated/dispersed nanoparticles in the presence of the Zn2+/Tyrosine are supported by scanning-electron microscope (SEM), transmission-electron microscope (TEM), atomic-force microscope (AFM), and dynamic-light scattering (DLS) investigations. Density-functional theory (DFT) studies confirm an "On-Off" twisted intramolecular charge transfer/photo-induced electron transfer (TICT/PET) and "On-Off-On" PET mechanisms for AIEE and sensors, respectively. B16-F10 cellular and zebrafish imaging are conducted to support the applications of AIEE and sensors. [ABSTRACT FROM AUTHOR]

Summary: Circulating tumor cells (CTCs) are tumor cells that shed from the primary tumor and intravasate into the peripheral blood circulation system responsible for metastasis. Sensitive detection of CTCs from clinical samples can serve as an effective tool in cancer diagnosis and prognosis through liquid biopsy. Current CTC detection technologies mainly reply on the biomarker-mediated platforms including magnetic beads, microfluidic chips or size-sensitive microfiltration which can compromise detection sensitivity due to tumor heterogeneity. A more sensitive, biomarker independent CTCs isolation technique has been recently developed with the surface-charged superparamagnetic nanoprobe capable of different EMT subpopulation CTC capture from 1 mL clinical blood. In this review, this new strategy is compared with the conventional techniques on biomarker specificity, impact of protein corona, effect of glycolysis on cell surface charge, and accurate CTC identification. Correlations between CTC enumeration and molecular profiling in clinical blood and cancer prognosis are provided for clinical cancer management.

Fluorescence and photoacoustic imaging techniques offer valuable insights into cell- and tissue-level processes. However, these optical imaging modalities are limited by scattering and absorption in tissue, resulting in the low-depth penetration of imaging. Contrast-enhanced imaging in the near-infrared window improves imaging penetration by taking advantage of reduced autofluorescence and scattering effects. Current contrast agents for fluorescence and photoacoustic imaging face several limitations from photostability and targeting specificity, highlighting the need for a novel imaging probe development. This review covers a broad range of near-infrared fluorescent and photoacoustic contrast agents, including organic dyes, polymers, and metallic nanostructures, focusing on their optical properties and applications in cellular and animal imaging. Similarly, we explore encapsulation and functionalization technologies toward building targeted, nanoscale imaging probes. Bioimaging applications such as angiography, tumor imaging, and the tracking of specific cell types are discussed. This review sheds light on recent advancements in fluorescent and photoacoustic nanoprobes in the near-infrared window. It serves as a valuable resource for researchers working in fields of biomedical imaging and nanotechnology, facilitating the development of innovative nanoprobes for improved diagnostic approaches in preclinical healthcare.

Bacterial contamination is an important factor causing food security issues. Among the bacteria, Escherichia coli is one of the main pathogens of food-borne microorganisms. However, traditional bacterial detection approaches cannot meet the requirements of real-time and on-site detection. Thus, it is of great significance to develop a rapid and accurate detection of bacteria in food to ensure food safety and safeguard human health. The pathogen heat-treatment module was designed in this paper based on the techniques including nanoprobe, pathogen heat-treatment, graphene transparent electrode (GTE), and adenosine triphosphate (ATP) bioluminescence technology. The system mainly consists of two parts: one is the optical detection unit; the other is the data processing unit. And it can quickly and automatically detect the number of bacterial colonies in food such as milk etc. The system uses not only the probe to capture and enrich E. coli by antigen-antibody interaction but also the heat treatment to increase the amount of ATP released from bacterial cells within five minutes. To enhance the detecting accuracy and sensitivity, the electric field generated by GTE is adopted in the system to enrich ATP. Compared to the other conventional methods, the linear correlation coefficient of the system can be reached 0.975, and the system meets the design requirements. Under the optimal experimental conditions, the detection can be completed within 25 min, and the detectable concentration of bacteria is in the range of 3.1 × 101–106 CFU/mL. This system satisfies the demands of a fast and on-site inspection. [ABSTRACT FROM AUTHOR]

At present, clinical diagnosis of breast cancer is based on the combination of pathological typesand molecular typing (immunohistochemistry). Yet, it is invasive and unable to show the relationship between keybiological molecules and clinical key information in situ and in real time. This paper introduces the latest researchprogress of molecular classification of breast cancer using molecular imaging technology. Fluorescence imaginghas high sensitivity and does not rely too much on image analysis. Thus, molecular classification information ofbreast cancer can be obtained in real time and multi-channel, quantitatively or semi quantitatively by using the cor‐responding fluorescent probes. Therefore, the development of safe and efficient near-infrared fluorescent molecu‐lar probes with strong tissue penetration is the focus of future fluorescence imaging technology and molecular clas‐sification of breast cancer

Abstract Fe-based single-atomic site catalysts (SASCs), with the natural metalloproteases-like active site structure, have attracted widespread attention in biocatalysis and biosensing. Precisely, controlling the isolated single-atom Fe-N-C active site structure is crucial to improve the SASCs’ performance. In this work, we use a facile ion-imprinting method (IIM) to synthesize isolated Fe-N-C single-atomic site catalysts (IIM-Fe-SASC). With this method, the ion-imprinting process can precisely control ion at the atomic level and form numerous well-defined single-atomic Fe-N-C sites. The IIM-Fe-SASC shows better peroxidase-like activities than that of non-imprinted references. Due to its excellent properties, IIM-Fe-SASC is an ideal nanoprobe used in the colorimetric biosensing of hydrogen peroxide (H2O2). Using IIM-Fe-SASC as the nanoprobe, in situ detection of H2O2 generated from MDA-MB-231 cells has been successfully demonstrated with satisfactory sensitivity and specificity. This work opens a novel and easy route in designing advanced SASC and provides a sensitive tool for intracellular H2O2 detection.

Bioaffinity nanoprobes are a type of biosensor that utilize the specific binding properties of biological molecules, such as antibodies, enzymes, and nucleic acids, for the detection of foodborne pathogens. These probes serve as nanosensors and can provide highly specific and sensitive detection of pathogens in food samples, making them an attractive option for food safety testing. The advantages of bioaffinity nanoprobes include their ability to detect low levels of pathogens, rapid analysis time, and cost-effectiveness. However, limitations include the need for specialized equipment and the potential for cross-reactivity with other biological molecules. Current research efforts focus on optimizing the performance of bioaffinity probes and expanding their application in the food industry. This article discusses relevant analytical methods, such as surface plasmon resonance (SPR) analysis, Fluorescence Resonance Energy Transfer (FRET) measurements, circular dichroism, and flow cytometry, that are used to evaluate the efficacy of bioaffinity nanoprobes. Additionally, it discusses advances in the development and application of biosensors in monitoring foodborne pathogens.

[Display omitted] • A new class of NIR-LED photostimulated luminescence (PSL) nanoprobes based on SrS:Eu2+,Dy3+@SrS NCs is proposed. • The stimulation band of these SrS:Eu2+,Dy3+@SrS NCs spans from 700 to 1400 nm. • A PSL duration time longer than 2 h is achieved upon 808-nm LED stimulation. • These SrS:Eu2+,Dy3+@SrS nanoprobes are exploited for tumor-targeted imaging in zebrafish. Near-infrared (NIR) photostimulated luminescence (PSL) nanocrystals (NCs) exhibit deep penetrability and low autofluorescence, recently evoking extensive interest for their application in biosensing. Nevertheless, most of the NIR PSL NCs encounter substantial constraints in biomedicine applications, primarily stemming from the necessity of high-power diode laser stimulation or their larger particle size. Herein, we design a new class of NIR light-emitting diode (LED) PSL NCs based on SrS:Eu2+ NCs, which were coated with SrS shell to improve their stability and photoluminescence (PL) intensity. The trap depth and density of the NCs were further tailored through thermal annealing and Dy3+ co-doping, resulting in efficient NIR PSL with a duration time longer than 2 h by stimulation with an NIR LED in a broad region within 700–1400 nm. Benefiting from their excellent NIR PSL, we showcased the potential of SrS:Eu2+,Dy3+@SrS NCs as sensitive nanoprobes for tumor-targeted imaging in zebrafish with a signal-to-noise ratio of 18.9. These findings demonstrate the significant promise of the proposed SrS:Eu2+,Dy3+@SrS nanoprobes for in vivo bioimaging, which may pave the way for the development of effective NIR PSL nanoprobes for diverse bioapplications in the future. [ABSTRACT FROM AUTHOR]

Drug resistance and relapse lead to high mortality in acute myeloid leukemia, and studies have shown that CXCR4 overexpression is highly correlated with poor prognosis and drug resistance in leukemia cells. Isolation and detection of AML cells with CXCR4 overexpression will be crucial to the treatment of AML. In this paper, magnetic nanoparticles were firstly prepared successfully by high-temperature thermal decomposition method, and then characterized by TEM, VSM and DLS. Subsequently CXCR4-targeted magnetic fluorescent nanoprobes conjugated with antibody 12G5 were constructed by stepwise coupling. In cell experiments, the obtained probes demonstrated excellent targeting efficacy to CXCR4 overexpressed AML cells HL-60. In addition, HL-60 cells labelled with the magnetic probes can be magnetic isolated successfully in one microfluidics chip, with efficiency of 82.92 ± 7.03%. Overall, this method utilizes the superiority of superparamagnetic nanomaterials and microfluidic technology to achieve the enrichment and capture of drug-resistant cells in a microfluidic chip, providing a new idea for the isolation and detective of drug-resistant acute myeloid leukemia cells. [ABSTRACT FROM AUTHOR]

The development of nanomedicine has recently achieved several breakthroughs in the field of cancer treatment; however, biocompatibility and targeted penetration of these nanomaterials remain as limitations, which lead to serious side effects and significantly narrow the scope of their application. The self-assembly of intermediate filaments with arginine–glycine–aspartate (RGD) peptide (RGD-IFP) was triggered by the hydrophobic cationic molecule 7-amino actinomycin D (7-AAD) to synthesize a bifunctional nanoparticle that could serve as a fluorescent imaging probe to visualize tumor treatment. The designed RGD-IFP peptide possessed the ability to encapsulate 7-AAD molecules through the formation of hydrogen bonds and hydrophobic interactions by a one-step method. This fluorescent nanoprobe with RGD peptide could be targeted for delivery into tumor cells and released in acidic environments such as endosomes/lysosomes, ultimately inducing cytotoxicity by arresting tumor cell cycling with inserted DNA. It is noteworthy that the RGD-IFP/7-AAD nanoprobe tail-vein injection approach demonstrated not only high tumor-targeted imaging potential, but also potent antitumor therapeutic effects in vivo. The proposed strategy may be used in peptide-driven bifunctional nanoparticles for precise imaging and cancer therapy. Super-sensitive bifunctional nanoprobe that showed strong tumor-targeted imaging and antitumor therapeutic effects has been synthesized by one-step. This nanoparticle penetrated tumor cells to induce cell cycle arresting for cytotoxicity. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Probiotics comprise a large group of microorganisms, which have different properties and thus confer different benefits. The use of probiotics has shown promising results in the management of diarrheal diseases. While the availability of probiotic products has flourished in the marketplace, there is limited guidance on the selection of probiotics for clinical use. This position paper is aimed at informing clinicians about the proper selection criteria of probiotics based on current evidence on strain‐specific efficacy and safety for the management of diarrheal diseases. Members of the working group discussed issues on probiotic use in clinical practice, which were then drafted into statements. Literature to support or refute the statements were gathered through a search of medical literature from 2011 to 2020. Recommendations were formulated based on the drafted statements and evidence gathered, revised as necessary, and finalized upon agreement of all members. Twelve statements and recommendations were developed covering the areas of quality control in the manufacturing of probiotics, criteria for selection of probiotics, and established evidence for use of probiotics in diarrheal diseases in adults and children. Recommendations for the use of specific probiotic strains in clinical practice were categorized as proven and probable efficacy based on strength of evidence. Robust evidence is available to support the use of probiotics for diarrheal diseases in clinical practice. Based on the results obtained, we strongly advocate the careful evaluation of products, including manufacturing practices, strain‐specific evidence, and contraindications for at‐risk populations when choosing probiotics for use in clinical practice.

Xiumei Tian1 ,* Ao Zeng1 ,* Ziying Liu,1 Cunjing Zheng,2 Yuezi Wei,1 Peiheng Yang,1 Minru Zhang,1 Fanwen Yang,1 Fukang Xie1 1School of Basic Medical Sciences, Affiliated Stomatology Hospital, Guangzhou Medical University, Guangzhou 510182, People’s Republic of China; 2Department of Histology and Embryology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou 510080, People’s Republic of China*These authors contributed equally to this workCorrespondence: Fukang Xie Tel +86 20 136 4231 6682Email 378141679@qq.comFanwen Yang Tel +86 20 135 0308 0690Fax +86 20 3710 3509Email yangfanwen@163.comBackground: Understanding the biocompatibility and biointeractions of nano-carbon quantum dots (nano-CQDs) in vitro and in vivo is important for assessing their potential risk to human health. In the previous research, the physical properties of CQDs synthesized by the laser ablation in liquid (LAL) method were analyzed in detail; however, possible bioapplications were not considered.Materials and Methods: CQDs were prepared by LAL and characterized by atomic force microscopy, fluorescence lifetime, absorption spectrum, Fourier-transform infrared spectroscopy, and dynamic light scattering. Their biocompatibility was evaluated in vitro using assays for cytotoxicity, apoptosis, and biodistribution and in vivo using immunotoxicity and the relative expression of genes. Cells were measured in vitro using fluorescence-lifetime imaging microscopy to analyze the biointeractions between CQDs and intracellular proteins.Results: There were no significant differences in biocompatibility between the CQDs and the negative control. The intracellular interactions had no impact on the optical imaging of CQDs upon intake by cells. Optical imaging of zebrafish showed the green fluorescence was well dispersed.Conclusion: We have demonstrated that the CQDs have an excellent biocompatibility and can be used as efficient optical nanoprobes for cell tracking and biomedical labeling except for L929 and PC-3M cells.Keywords: nanoprobe, immunotoxicity, biodistribution, biointeraction, optical imaging

Bimodal imaging combines two imaging modalities in order to benefit from their advantages and compensate the limitations of each modality. This technique could accurately detect diseases for diagnostic purposes. Nanoparticles simultaneously offer diagnostic data via various imaging modalities owing to their unique properties. Moreover, bimodal nanoprobes could be incorporated into theranostic systems for the design of multifunctional agents. Magnetic resonance imaging (MRI) and computed tomography (CT) are frequently used as noninvasive imaging modalities. These powerful, noninvasive diagnostic techniques used for the imaging of soft and hard tissues, respectively. However, MRI has low sensitivity and is not suitable for the imaging of bony structures. On the other hand, low soft tissue contrast is a major limitation of CT. Therefore, the development of various contrast agents that are proper for bimodal MRI/CT nanoprobes could largely influence modern medicine. This review aimed to specifically focus on the imaging properties of bimodal MRI/CT nanoprobes and their biomedical applications.