Due to high tissue penetration depth and low autofluorescence backgrounds, near-infrared (NIR) fluorescence imaging has recently become an advantageous diagnostic technique used in a variety of fields. However, most of the NIR fluorophores do not have therapeutic delivery capabilities, exhibit low photostabilities, and raise toxicity concerns. To address these issues, we developed and tested five types of biocompatible graphene quantum dots (GQDs) exhibiting spectrally-separated fluorescence in the NIR range of 928-1053 nm with NIR excitation. Their optical properties in the NIR are attributed to either rare-earth metal dopants (Ho-NGQDs, Yb-NGQDs, Nd-NGQDs) or defect-states (nitrogen doped GQDS (NGQDs), reduced graphene oxides) as verified by Hartree-Fock calculations. Moderate up to 1.34% quantum yields of these GQDs are well-compensated by their remarkable >4 h photostability. At the biocompatible concentrations of up to 0.5-2 mg ml-1 GQDs successfully internalize into HEK-293 cells and enable in vitro imaging in the visible and NIR. Tested all together in HEK-293 cells five GQD types enable simultaneous multiplex imaging in the NIR-I and NIR-II shown for the first time in this work for GQD platforms. Substantial photostability, spectrally-separated NIR emission, and high biocompatibility of five GQD types developed here suggest their promising potential in multianalyte testing and multiwavelength bioimaging of combination therapies.

Spectral fingerprinting has emerged as a powerful tool that is adept at identifying chemical compounds and deciphering complex interactions within cells and engineered nanomaterials. Using near-infrared (NIR) fluorescence spectral fingerprinting coupled with machine learning techniques, we uncover complex interactions between DNA-functionalized single-walled carbon nanotubes (DNA-SWCNTs) and live macrophage cells, enabling in situ phenotype discrimination. Utilizing Raman microscopy, we showcase statistically higher DNA-SWCNT uptake and a significantly lower defect ratio in M1 macrophages compared to M2 and naive phenotypes. NIR fluorescence data also indicate that distinctive intraendosomal environments of these cell types give rise to significant differences in many optical features, such as emission peak intensities, center wavelengths, and peak intensity ratios. Such features serve as distinctive markers for identifying different macrophage phenotypes. We further use a support vector machine (SVM) model trained on SWCNT fluorescence data to identify M1 and M2 macrophages, achieving an impressive accuracy of >95%. Finally, we observe that the stability of DNA-SWCNT complexes, influenced by DNA sequence length, is a crucial consideration for applications, such as cell phenotyping or mapping intraendosomal microenvironments using AI techniques. Our findings suggest that shorter DNA-sequences like GT6 give rise to more improved model accuracy (>87%) due to increased active interactions of SWCNTs with biomolecules in the endosomal microenvironment. Implications of this research extend to the development of nanomaterial-based platforms for cellular identification, holding promise for potential applications in real time monitoring of in vivo cellular differentiation.

BACKGROUND: Cell-surface proteins, which are closely associated with various physiological and pathological processes, have drawn much attention in drug discovery and disease diagnosis. Thus, wash-free imaging of the target cell-surface protein under its native environment is critical and helpful for early detection and prognostic evaluation of diseases.
RESULTS: To minimize the interference from autofluorescence and fit the penetration depth towards tissue samples, we developed a fluorogenic antibody-based probe, Ab-Cy5.5, which will liberate > 5-fold turn-on near-infrared (NIR) emission in the presence of its target antigen within 10 min.
CONCLUSIONS: By taking advantage of the fluorescence-quenched dimeric H-aggregation of Cy5.5, Ab-Cy5.5 with Cy5.5 attached at the N-terminus showed negligible background signal, allowing direct imaging of the target cell-surface protein in both living cells and tissue samples without washing.

SO2 derivatives, sulfite/bisulfite, are widely employed in both the food processing and drug synthesis industries. Despite their widespread application, excessive levels of sulfite/bisulfite can negatively impact human health. Most probes for detecting sulfite/bisulfite are restricted by their fluorescence within the visible spectrum range and poor solubility in aqueous solution, which limit their use in food testing and biological imaging. Herein, a near-infrared probe comprising of the cyanopyridine cyanine skeleton, 4-((Z)-2-((E)-2-chloro-3-(2-cyano-2-(1-methylpyridine-4(1H)-ylidene)ethylidene)cyclohex-1-en-1-yl)-1-cyanovinyl)-1-methylpyridin-1-ium (abbreviated as CCP), was developed. This probe enables precise quantification of bisulfite (HSO3-) in almost pure buffered solutions, showing a near-infrared fluorescence emission at 784 nm with an impressively low detection limit of 0.32 μM. The probe stands out for its exceptional selectivity, minimal susceptibility to interference, and strong adaptability. The probe CCP utilizes the CC bond to trigger a near-infrared fluorescence quenching reaction with HSO3- via nucleophilic addition, which effectively disrupts the large delocalization within the molecule for accurate HSO3- identification. Moreover, the probe has been successfully applied in detecting HSO3- in various food products and living cells, simplifying the measurement of HSO3- content in water samples. This advancement not only enhances the analytical capabilities but also contributes to ensuring food safety and environmental protection. ENVIRONMENTAL IMPLICATION: SO2 derivatives including sulfite/bisulfite, serving dual roles as preservatives and antioxidants, have widespread application across various sectors including food preservation, water sanitation, and the pharmaceutical industry. Despite their widespread application, excessive levels of sulfite/bisulfite can affect human health. Developing methods for precisely and sensitively detecting sulfite/bisulfite in food products and biological samples is important for ensuring food safety and environmental protection. Here, a sensitive near-infrared and multifunctional fluorescent probe in a 99.9 % buffered solution, along with water gel encapsulation, has been successfully applied for the detection of bisulfite in food, authentic water samples, and biological cells.

Activity-based detection of γ-Glutamyltranspeptidase (GGT) using near-infrared (NIR) fluorescent probes is a promising strategy for early cancer diagnosis. Although NIR pyridinium probes show high performance in biochemical analysis, the aggregation of both the probes and parental fluorochromes in biological environments is prone to result in a low signal-to-noise ratio (SBR), thus affecting their clinical applications. Here, we develop a GGT-activatable aggregate probe called OTBP-G for two-photon fluorescence imaging in various biological environments under 1040 nm excitation. By rationally tunning the hydrophilicity and donor-acceptor strength, we enable a synergistic effect between twisted intramolecular charge transfer and intersystem crossing processes and realize a perfect dark state for OTBP-G before activation. After the enzymatic reaction, the parental fluorochrome exhibits bright aggregation-induced emission peaking at 670 nm. The fluorochrome-to-probe transformation can induce 1000-fold fluorescence ON/OFF ratio, realizing in vitro GGT detection with an SBR > 900. Activation of OTBP-G occurs within 1 min in vivo, showing an SBR > 400 in mouse ear blood vessels. OTBP-G can further enable the early detection of pulmonary metastasis in breast cancer by topically spraying, outperforming the clinical standard hematoxylin and eosin staining. We anticipate that the in-depth study of OTBP-G can prompt the development of early cancer diagnosis and tumor-related physiological research. Moreover, this work highlights the crucial role of hydrophilicity and donor-acceptor strength in maximizing the ON/OFF ratio of the TICT probes and showcases the potential of OTBP as a versatile platform for activity-based sensing.

BACKGROUND: Colorectal cancer (CRC) is a prevalent digestive malignancy with significant global mortality and morbidity rates. Improving diagnostic capabilities for CRC and investigating novel therapeutic approaches are pressing clinical imperatives. Additionally, carcinoembryonic antigen (CEA) has emerged as a highly promising candidate for both colorectal tumor imaging and treatment.
METHODS: A novel active CEA-targeting nanoparticle, CEA(Ab)-MSNs-ICG-Pt, was designed and synthesized, which served as a tumor-specific fluorescence agent to help in CRC near-infrared (NIR) fluorescence imaging. In cell studies, CEA(Ab)-MSNs-ICG-Pt exhibited specific targeting to RKO cells through specific antibody-antigen binding of CEA, resulting in distribution both within and around these cells. The tumor-targeting-specific imaging capabilities of the nanoparticle were determined through in vivo fluorescence imaging experiments. Furthermore, the efficacy of the nanoparticle in delivering chemotherapeutics and its killing effect were evaluated both in vitro and in vivo.
RESULTS: The CEA(Ab)-MSNs-ICG-Pt nanoparticle, designed as a novel targeting agent for carcinoembryonic antigen (CEA), exhibited dual functionality as a targeting fluorescent agent. This CEA-targeting nanoparticle showed exceptional efficacy in eradicating CRC cells in comparison to individual treatment modalities. Furthermore, it exhibits exceptional biosafety and biocompatibility properties. CEA(Ab)-MSNs-ICG-Pt exhibits significant promise due to its ability to selectively target tumors through NIR fluorescence imaging and effectively eradicate CRC cells with minimal adverse effects in both laboratory and in vivo environments.
CONCLUSIONS: The favorable characteristics of CEA(Ab)-MSNs-ICG-Pt offer opportunities for its application in chemotherapeutic interventions, tumor-specific NIR fluorescence imaging, and fluorescence-guided surgical procedures.

BACKGROUND: The identification of the intersegmental plane (ISP) is a crucial step in segmentectomy for children with congenital pulmonary airway malformation (CPAM) due to complex anatomical variations. However, there is very limited literature available on this aspect specifically for infant. In this study, we compared the intravenous indocyanine green (ICG)-guided near-infrared fluorescence (NIRF) imaging method with the modified inflation-deflation method in terms of their perioperative characteristics and summarized our experience.
METHODS: From June 2021 to November 2022, the data of 83 patients with CPAM who underwent segmentectomy by video-assisted thoracoscopic surgery were retrospectively reviewed. Twenty-eight patients underwent ICG-guided NIRF method, and 56 patients underwent the modified inflation-deflation method, characteristics and clinical outcomes were compared.
RESULTS: The median age of the patients was 4.99 months (4.99 ± 1.51) with a mean body weight of 7.54 kg (7.54 ± 1.99). Both methods could accurately identify the ISP. The time taken to clearly display the ISP was shorter in ICG group than in the modified inflation-deflation group (0.18 ± 0.08 vs. 6.49 ± 1.67 min; P < 0.001), and the surgical duration (61.32 ± 14.28 vs. 88.18 ± 8.03 min; P < 0.001) were significantly shorter in the ICG group too. The two groups exhibited differences in the length of chest tube drainage (1.75 ± 1.24 vs. 2.36 ± 1.54 days; P = 0.072) and the length of hospital stay (4.61 ± 1.75 vs. 5.20 ± 3.07 days; P = 0.078), however, the differences were not statistically significant. There were no significant differences between the two groups in the blood lost and postoperative complications. At a follow-up of more than 1 year after operation, all patients had recovered well without recurrence.
CONCLUSIONS: According to our experience, the ICG-guided NIRF method was safe and feasible for infants during thoracoscopic segmentectomy, it can quickly display the ISP and shorten the surgical duration compared with the modified inflation-deflation method.

UNASSIGNED: The aim of this review was to assess the outcomes of partial nephrectomy using indocyanine green (ICG) regarding ischemia time, positive surgical margins (PSM), estimated blood loss (EBL) and estimated GFR reduction while also suggesting the optimal dosage scheme.
UNASSIGNED: A systematic review was performed using Medline (PubMed), ClinicalTrials.gov, and Cochrane Library (CENTRAL) databases, in concordance with the PRISMA statement. Studies in English regarding the use of indocyanine green in partial nephrectomy were reviewed. Reviews and meta-analyses, editorials, perspectives, and letters to the editors were excluded.
UNASSIGNED: Individual ICG dose was 5 mg in most of the studies. The mean warm ischemia time (WIT) on each study ranged from 11.6 minutes to 27.2 minutes. The reported eGFR reduction ranged from 0% to 15.47%. Lowest mean EBL rate was 48.2 ml and the highest was 347 ml. Positive surgical margin rates were between 0.3% to 11%.
UNASSIGNED: Indocyanine green seems to be a useful tool in partial nephrectomy as it can assist surgeons in identifying tumor and its related vasculature. Thereby, warm ischemia time can be reduced and, in some cases, selective ischemia can be implemented leading to better renal functional preservation.

Early diagnosis of gastrointestinal (GI) diseases is important to effectively prevent carcinogenesis. Capsule endoscopy (CE) can address the pain caused by wired endoscopy in GI diagnosis. However, existing CE approaches have difficulty effectively diagnosing lesions that do not exhibit obvious morphological changes. In addition, the current CE cannot achieve wireless energy supply and attitude control at the same time. Here, we successfully developed a novel near-infrared fluorescence capsule endoscopy (NIFCE) that can stimulate and capture near-infrared (NIR) fluorescence images to specifically identify subtle mucosal microlesions and submucosal lesions while capturing conventional white light (WL) images to detect lesions with significant morphological changes. Furthermore, we constructed the first synergetic system that simultaneously enables multi-attitude control in NIFCE and supplies long-term power, thus addressing the issue of excessive power consumption caused by the NIFCE emitting near-infrared light (NIRL). We performed in vivo experiments to verify that the NIFCE can specifically \"light up\" tumors while sparing normal tissues by synergizing with probes actively aggregated in tumors, thus realizing specific detection and penetration. The prototype NIFCE system represents a significant step forward in the field of CE and shows great potential in efficiently achieving early targeted diagnosis of various GI diseases.

In situ monitoring of bone regeneration enables timely diagnosis and intervention by acquiring vital biological parameters. However, an existing gap exists in the availability of effective methodologies for continuous and dynamic monitoring of the bone tissue regeneration process, encompassing the concurrent visualization of bone formation and implant degradation. Here, we present an integrated scaffold designed to facilitate real-time monitoring of both bone formation and implant degradation during the repair of bone defects. Laponite (Lap), CyP-loaded mesoporous silica (CyP@MSNs) and ultrasmall superparamagnetic iron oxide nanoparticles (USPIO@SiO2) were incorporated into a bioink containing bone marrow mesenchymal stem cells (BMSCs) to fabricate functional scaffolds denoted as C@M/GLU using 3D bioprinting technology. In both in vivo and in vitro experiments, the composite scaffold has demonstrated a significant enhancement of bone regeneration through the controlled release of silicon (Si) and magnesium (Mg) ions. Employing near-infrared fluorescence (NIR-FL) imaging, the composite scaffold facilitates the monitoring of alkaline phosphate (ALP) expression, providing an accurate reflection of the scaffold\'s initial osteogenic activity. Meanwhile, the degradation of scaffolds was monitored by tracking the changes in the magnetic resonance (MR) signals at various time points. These findings indicate that the designed scaffold holds potential as an in situ bone implant for combined visualization of osteogenesis and implant degradation throughout the bone repair process.