RESUMEN
BACKGROUND: Drug-induced liver injury (DILI) is the most important standard for the entrance of clinical drugs into the pharmaceutical market. The elevation of superoxide anion (O2â¢-) during drug metabolism can mediate apoptosis of hepatocytes and further generation of liver damage. Therefore, developing an effective imaging method for evaluating O2â¢- levels during DILI is of great importance. However, current reported O2â¢- fluorescent probes either use short excitation wavelengths or a single intensity detection system, limiting the accurate quantification of O2â¢- in deep tissue in vivo. RESULTS: We developed a NIR-excited ratiometric nanoprobe (CyD-UCNPs) by assembly of O2â¢--sensitive hemicyanine dyes (CyD) on the surface of Tm/Er-codoped upconversion nanoparticles (UCNPs) with the assistance of α-cyclodextrin, which exhibited a robust "turn-on" ratiometric sensing signal. In vitro experiments indicated that CyD-UCNPs respond well to O2â¢- with high selectivity. Furthermore, by taking advantage of the outstanding optical properties produced by the luminescent resonance energy transfer between the UCNPs and CyD upon the excitation of 980 nm, the ratiometric upconversion luminescence signal of CyD-UCNPs was successfully utilized to monitor the fluctuation of O2â¢- levels under phorbol-12-myristate-13-acetate (PMA)/cisplatin-induced oxidative stress in living cells, liver tissues, and zebrafish. More importantly, endogenous change in O2â¢- levels in the liver sites of mice during DILI and its prevention with L-carnitine was visualized using CyD-UCNPs. SIGNIFICANCE: This study provides a ratiometric NIR-excited imaging strategy for investigating the correlation between O2â¢- levels and DILI and its prevention, which is significant for early diagnosis of DILI and preclinical screening of anti-hepatotoxic drugs in vivo.
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Carbocianinas , Enfermedad Hepática Inducida por Sustancias y Drogas , Colorantes Fluorescentes , Rayos Infrarrojos , Nanopartículas , Superóxidos , Enfermedad Hepática Inducida por Sustancias y Drogas/diagnóstico por imagen , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Animales , Superóxidos/análisis , Superóxidos/metabolismo , Superóxidos/química , Ratones , Colorantes Fluorescentes/química , Carbocianinas/química , Nanopartículas/química , Humanos , Pez Cebra , Imagen Óptica , Transducción de Señal/efectos de los fármacosRESUMEN
Developing NIR-IIb luminescence probes with rapid visualization and a high penetration depth is essential for diabetes research. Combining a sensitizing switch with lanthanide-doped nanoparticles (LnNPs) has been employed to fabricate the NIR-IIb probes. However, these probes mainly adopt heptamethine cyanine dye as the antenna, and the NIR-IIb signal is activated by inhibiting the photoinduced electron transfer (PET) of the dye. Due to limited recognition units, this strategy makes many biomolecules undetectable, such as cysteine (Cys), which is closely related to diabetes. Herein, in this article, hemicyanine dye, NFL-OH, was verified as a new antenna to sensitize NIR-IIb emission from LnNPs. Unlike traditional cyanine dyes, hemicyanine's fluorescence intensity can also be modulated by intramolecular charge transfer (ICT), thereby expanding the range of detectable targets for NIR-IIb probes based on sensitization mechanism. Through switching the hemicyanine-sensitized NIR-IIb emission, we successfully fabricated an NFL-Cys-LnNPs' nanoprobe, which can effectively monitor Cys concentration in the liver of diabetic mice during diabetes progression and evaluate the efficacy of diabetic drugs. Our work not only presents an excellent tool for Cys imaging but also introduces new concepts for designing NIR-IIb probes.
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Cisteína , Diabetes Mellitus Experimental , Colorantes Fluorescentes , Animales , Ratones , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Diabetes Mellitus Experimental/inducido químicamente , Cisteína/química , Cisteína/análisis , Rayos Infrarrojos , Imagen Óptica , Nanopartículas/química , Carbocianinas/química , Progresión de la Enfermedad , Humanos , MasculinoRESUMEN
Metastatic breast cancer is a devastating disease with very limited therapeutic options, calling for new therapeutic strategies. Oncogenic miRNAs have been shown to be associated with the metastatic potential of breast cancer and are implicated in tumor cell migration, invasion, and viability. However, it can be difficult to deliver an inhibitory RNA molecule to the tissue of interest. To overcome this challenge and deliver active antisense oligonucleotides to tumors, we utilized magnetic iron oxide nanoparticles as a delivery platform. These nanoparticles target tissues with increased vascular permeability, such as sites of inflammation or cancer. Delivery of these nanoparticles can be monitored in vivo by magnetic resonance imaging (MRI) due to their magnetic properties. Translation of this therapeutic approach into the clinic will be more accessible because of its compatibility with this relevant imaging modality. They can also be labeled with other imaging reporters such as a Cy5.5 near-infrared optical dye for correlative optical imaging and fluorescence microscopy. Here, we demonstrate that nanoparticles labeled with Cy5.5 and conjugated to therapeutic oligomers targeting oncogenic miRNA-10b (termed MN-anti-miR10b, or "nanodrug") administered intravenously accumulate in metastatic sites, opening a possibility for therapeutic intervention of metastatic breast cancer.
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Carbocianinas , MicroARNs , Animales , Femenino , Ratones , MicroARNs/genética , MicroARNs/administración & dosificación , Carbocianinas/química , Neoplasias Mamarias Experimentales/patología , Neoplasias Mamarias Experimentales/metabolismo , Neoplasias Mamarias Experimentales/diagnóstico por imagen , Nanopartículas Magnéticas de Óxido de Hierro/química , Imagen por Resonancia Magnética/métodos , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/diagnóstico por imagen , Oligonucleótidos Antisentido/administración & dosificación , Oligonucleótidos Antisentido/químicaRESUMEN
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.
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Carbocianinas , Sulfitos , Espectroscopía Infrarroja Corta/métodos , Espectrometría de Fluorescencia/métodos , Piridinas/química , Carbocianinas/química , Sulfitos/análisis , Sulfitos/química , Estructura Molecular , Humanos , Células HeLa , Procesos Fotoquímicos , Límite de Detección , Hidrogeles/química , Análisis de los AlimentosRESUMEN
ConspectusDue to the advantages of spatiotemporal selectivity and inherent noninvasiveness, cancer phototherapy, which includes both photodynamic therapy (PDT) and photothermal therapy (PTT), has garnered significant attention in recent years as a promising cancer treatment. Despite the commendable progress in this field, persistent challenges remain. In PDT, limitations in dyes manifest as low intersystem crossing (ISC) efficiency and oxygen-dependent photoactivity, resulting in unsatisfactory performance, particularly under hypoxic conditions. Similarly, PTT encounters consistent insufficiencies in the photothermal conversion efficiency (PCE) of dyes. Additionally, the suboptimal phototherapeutic efficacy often exhibits a limited immune response. These factors collectively impose significant constraints on phototherapy in oncological applications, leading to limited tumor inhibition, tumor recurrence, and even metastasis.Unlike strategies that rely on external assistance with complicated systems, manipulating excited-state deactivation pathways in biocompatible dyes offers a universal way to systematically address these challenges. Our group has devoted considerable effort to achieving this goal. In this Account, we present and discuss our journey in optimizing excited-state energy-release pathways through regulating molecular charge transfer based on cyanine dyes, which are renowned for their exceptional photophysical properties and harmonious biocompatibility. The investigation begins with the introduction of amino groups in the meso position of a heptamethine cyanine dye, where the intramolecular charge transfer (ICT) effect causes a significant enlargement of the Stokes shift. Subsequently, ICT induced by introducing functional electron-deficient groups in cyanines is found to decrease the overlap of electron distribution or narrow the energy gaps of molecular frontier orbitals. Such modifications result in a reduction of the energy gaps between singlet and triplet states or an improvement in internal conversion, ultimately promoting phototherapy efficacy in both primary and distant tumors. Furthermore, with the intensification of the charge transfer effect aided by light, photoinduced intramolecular electron transfer occurs in some cyanines, leading to complete charge separation in the excited state. This process enhances the transition to the ground or triplet states, improving tumor phototherapy and inhibiting metastasis by increasing the PCE or the yield of reactive oxygen species, respectively. Shifting focus from intramolecular to intermolecular interactions, we successfully constructed and explored cyanines based on intermolecular charge transfer. These dyes, with excited-state dynamics mimicking natural photosynthesis, generate radicals and facilitate oxygen-independent hypoxic tumor PDT. Finally, we outlined the existing challenges and future directions for optimizing phototherapeutic efficacy by regulating molecular charge transfer. This Account provides molecular-level insights into improving phototherapeutic performance, offering valuable perspectives, and inspiring the development of functional dyes in other application fields.
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Carbocianinas , Neoplasias , Carbocianinas/química , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Colorantes/química , Colorantes/farmacología , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/uso terapéutico , Fármacos Fotosensibilizantes/farmacología , Fotoquimioterapia , Animales , Fototerapia/métodosRESUMEN
Glyoxal (GL) is a reactive α-dicarbonyl compound generated from glycated proteins in the Maillard reaction. It has attracted particular attention over the past few years because of its possible clinical significance in chronic and age-related diseases. In this work, a reaction-based red emission fluorescent probe GL1 has been synthesized successfully by grafting an alkyl group onto an amino group to regulate its selectivity for GL. Under physiological conditions, the fluorescence intensity of GL1 at 640 nm obviously increased with the increase of GL concentration, and it exhibited high selectivity for GL over other reactive carbonyl compounds, as well as a lower detection limit (0.021 µM) and a larger Stokes shift (112 nm). At the same time, GL1 can selectively accumulate in mitochondria and can be used to detect exogenous and endogenous GL in living cells with low cytotoxicity.
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Colorantes Fluorescentes , Glioxal , Fenilendiaminas , Glioxal/química , Humanos , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Fenilendiaminas/química , Fenilendiaminas/síntesis química , Carbocianinas/química , Células HeLa , Supervivencia Celular/efectos de los fármacos , Estructura Molecular , Imagen Óptica , Mitocondrias/metabolismoRESUMEN
The spread of multidrug-resistant mycobacterium strains requires the development of new approaches to combat diseases caused by these pathogens. For that, photodynamic inactivation (PDI) is a promising approach. In this study, a tricarbocyanine (TCC) is used for the first time as a near-infrared (740 nm) activatable PDI photosensitizer to kill mycobacteria with deep light penetration. For better targeting, a novel tricarbocyanine dye functionalized with two trehalose units (TCC2Tre) is developed. The photodynamic effect of the conjugates against mycobacteria, including Mycobacterium tuberculosis, is evaluated. Under irradiation, TCC2Tre causes more effective killing of mycobacteria compared to the photosensitizer without trehalose conjugation, with 99.99% dead vegetative cells of M. tuberculosis and M. smegmatis. In addition, effective photoinactivation of dormant forms of M. smegmatis is observed after incubation with TCC2Tre. Mycobacteria treated with TCC2Tre are more sensitive to 740 nm light than the Gram-positive Micrococcus luteus and the Gram-negative Escherichia coli. For the first time, this study demonstrates the proof of principle of in vitro PDI of mycobacteria including the fast-growing M. smegmatis and the slow-growing M. tuberculosis using near-infrared activatable photosensitizers conjugated with trehalose. These findings are useful for the development of new efficient alternatives to antibiotic therapy.
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Rayos Infrarrojos , Mycobacterium smegmatis , Mycobacterium tuberculosis , Fármacos Fotosensibilizantes , Trehalosa , Mycobacterium smegmatis/efectos de los fármacos , Mycobacterium smegmatis/efectos de la radiación , Trehalosa/farmacología , Trehalosa/química , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/efectos de la radiación , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química , Carbocianinas/química , Carbocianinas/farmacología , Fotoquimioterapia/métodosRESUMEN
The development of a non-invasive infection-specific diagnostic probe holds the potential to vastly improve early-stage detection of infection, enabling precise therapeutic intervention and potentially reducing the incidence of antibiotic resistance. Towards this goal, a commercially available bacteria-targeting Zinc(II)-dipicolylamine (ZnDPA)-derived fluorophore, PSVue794, was assessed as a photoacoustic (PA) imaging probe (PIP). A radiolabeled version of the dye, [99mTc]Tc-PSVue794, was developed to facilitate quantitative biodistribution studies beyond optical imaging methods, which showed a target-to-non-target ratio of 10.1 ± 1.1, 12 h post-injection. The ability of the PIP to differentiate between bacterial infection, sterile inflammation, and healthy tissue in a mouse model, was then evaluated via PA imaging. The PA signal in sites of sterile inflammation (0.062 ± 0.012 a.u.) was not statistically different from that of the background (0.058 ± 0.006 a.u.). In contrast, high PA signal was detected at sites of bacterial infection (0.176 ± 0.011 a.u.) as compared to background (0.081 ± 0.04 a.u., where P ≤ 0.03). This work demonstrates the potential of utilizing established fluorophores towards PAI and utilizing PAI as a modality in the distinction of bacterial infection from sites of sterile inflammation.
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Infecciones Bacterianas , Carbocianinas , Colorantes Fluorescentes , Técnicas Fotoacústicas , Técnicas Fotoacústicas/métodos , Animales , Ratones , Carbocianinas/química , Colorantes Fluorescentes/química , Infecciones Bacterianas/diagnóstico por imagen , Distribución Tisular , Femenino , Modelos Animales de Enfermedad , Ácidos Picolínicos/químicaRESUMEN
The protein-induced fluorescence change technique was employed to investigate the interactions between proteins and their DNA substrates modified with the Cy3 fluorophore. It has been reported that the human hepatoma-derived growth factor (HDGF), containing the chromatin-associated N-terminal proline-tryptophan-tryptophan-proline (PWWP) domain (the N-terminal 100 amino acids of HDGF) capable of binding the SMYD1 promoter, participates in various cellular processes and is involved in human cancer. This project investigated the specific binding behavior of HDGF, the PWWP domain, and the C140 domain (the C-terminal 140 amino acids of HDGF) sequentially using protein-induced fluorescence change. We found that the binding of HDGF and its related proteins on Cy3-labeled 15 bp SMYD1 dsDNA will cause a significant decrease in the recorded Cy3 fluorophore intensity, indicating the occurrence of protein-induced fluorescence quenching. The dissociation equilibrium constant was determined by fitting the bound fraction curve to a binding model. An approximate 10-time weaker SMYD1 binding affinity of the PWWP domain was found in comparison to HDGF. Moreover, the PWWP domain is required for DNA binding, and the C140 domain can enhance the DNA binding affinity. Furthermore, we found that the C140 domain can regulate the sequence-specific binding capability of HDGF on SMYD1.
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Proteínas de Unión al ADN , ADN , Péptidos y Proteínas de Señalización Intercelular , Unión Proteica , Humanos , Péptidos y Proteínas de Señalización Intercelular/química , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , ADN/química , ADN/metabolismo , Dominios Proteicos , Sitios de Unión , Carbocianinas/química , Proteínas Musculares , Factores de TranscripciónRESUMEN
Efficient delivery of nanoparticles (NPs) to plants is important for agricultural application. However, to date, we still lack knowledge about how NPs' charge matters for its translocation pathway, i.e., symplastic and apoplastic pathways, in plants. In this study, we synthesized and used negatively charged citrate sourced carbon dots (C-CDs, -37.97 ± 1.89 mV), Cy5 coated C-CDs (Cy5-C-CDs, -41.90 ± 2.55 mV), positively charged PEI coated carbon dots (P-CDs, +43.03 ± 1.71 mV), and Cy5 coated P-CDs (Cy5-P-CDs, +48.80 ± 1.21 mV) to investigate the role of surface charges and coatings on the employed translocation pathways (symplastic and apoplastic pathways) of charged NPs in plants. Our results showed that, different from the higher fluorescence intensity of P-CDs and Cy5-P-CDs in extracellular than intracellular space, the fluorescence intensity of C-CDs and Cy5-C-CDs was similar between intracellular and extracellular space in cucumber and cotton roots. It suggests that the negatively charged CDs were translocated via both symplastic and apoplastic pathways, but the positively charged CDs were mainly translocated via the apoplastic pathway. Furthermore, our results showed that root applied negatively charged C-CDs demonstrated higher leaf fluorescence than did positively charged P-CDs in both cucumber (8.09 ± 0.99 vs 3.75 ± 0.23) and cotton (7.27 ± 1.06 vs 3.23 ± 0.22), indicating that negatively charged CDs have a higher translocation efficiency from root to leaf than do positively charged CDs. It should be noted that CDs do not affect root cell activities, ROS level, and photosynthetic performance in cucumber and cotton, showing its good biocompatibility. Overall, this study not only figured out that root applied negatively charged CDs employed both symplastic and apoplastic pathways to do the transportation in roots compared with mainly the employment of apoplastic pathway for positively charge CDs, but also found that negatively charge CDs could be more efficiently translocated from root to leaf than positively charged CDs, indicating that imparting negative charge to NPs, at least CDs, matters for its efficient delivery in crops.
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Carbono , Raíces de Plantas , Puntos Cuánticos , Carbono/química , Carbono/metabolismo , Puntos Cuánticos/química , Puntos Cuánticos/metabolismo , Raíces de Plantas/metabolismo , Raíces de Plantas/química , Cucumis sativus/metabolismo , Carbocianinas/químicaRESUMEN
3D bioprinting with cell-laden materials is an emerging technique for fabricating functional tissue constructs. However, current cell-laden bioinks often lack sufficient cytocompatibility with commonly used UV-light sources. In this study, green to red photoinduced hydrogel crosslinking was obtained by introducing synthesized biosafety photoinitiators and used in light-based direct ink writing (DIW) 3D printing for enabling cell encapsulation successfully. The novel type II photointiators contain iodonium (ONI) and synthesized cyanine dyes CZBIN, TDPABIN, Col-SH-CZ, and Col-SH-TD with strong absorption in the range of 400-600 nm. Collagen-based macromolecule dyes Col-SH-CZ and Col-SH-TD showed excellent cytocompatibility. The photochemistry of these photoinitiators revealed an efficient photoinduced electron transfer (PET) process from the singlet excited states of the dyes to iodonium (ONI), facilitating the crosslinking of the biogels. L929 cells were encapsulated in Gel-MA hydrogels containing various photoinitiating systems and exposed to near-ultraviolet, green, or red LED irradiation. DIW-type 3D printing of Gel-MA bioink with L929 cells was also evaluated. The cell viability achieved with green light encapsulation reached 90 %. This novel approach offers promising prospects for bioprinting functional tissues with enhanced cytocompatibility under visible light conditions.
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Colágeno , Hidrogeles , Colágeno/química , Animales , Ratones , Hidrogeles/química , Impresión Tridimensional , Línea Celular , Carbocianinas/química , Luz , Bioimpresión/métodos , Supervivencia Celular/efectos de los fármacos , Ingeniería de Tejidos/métodos , Andamios del Tejido/químicaRESUMEN
Significance: Fluorescent organic dyes provide imaging capabilities at cellular and sub-cellular levels. However, a common problem associated with some of the existing dyes such as the US FDA-approved indocyanine green (ICG) is their weak fluorescence emission. Alternative dyes with greater emission characteristics would be useful in various imaging applications. Complementing optical imaging, magnetic resonance (MR) imaging enables deep tissue imaging. Nano-sized delivery systems containing dyes with greater fluorescence emission as well as MR contrast agents present a promising dual-mode platform with high optical sensitivity and deep tissue imaging for image-guided surgical applications. Aim: We have engineered a nano-sized platform, derived from erythrocyte ghosts (EGs), with dual near-infrared fluorescence and MR characteristics by co-encapsulation of a brominated carbocyanine dye and gadobenate dimeglumine (Gd-BOPTA). Approach: We have investigated the use of three brominated carbocyanine dyes (referred to as BrCy106, BrCy111, and BrCy112) with various degrees of bromination, structural symmetry, and acidic modifications for encapsulation by nano-sized EGs (nEGs) and compared their resulting optical characteristics with nEGs containing ICG. Results: We find that asymmetric dyes (BrCy106 and BrCy112) with one dibromobenzene ring offer greater fluorescence emission characteristics. For example, the relative fluorescence quantum yield ( Ï ) for nEGs fabricated using 100 µ M of BrCy112 is â¼ 41 -fold higher than nEGs fabricated using the same concentrations of ICG. The dual-mode nEGs containing BrCy112 and Gd-BOPTA show a nearly twofold increase in their Ï as compared with their single optical mode counterpart. Cytotoxicity is not observed upon incubation of SKOV3 cells with nEGs containing BrCy112. Conclusions: Erythrocyte nano-ghosts with dual optical and MR characteristics may ultimately prove useful in various biomedical imaging applications such as image-guided tumor surgery where MR imaging can be used for tumor staging and mapping, and fluorescence imaging can help visualize small tumor nodules for resection.
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Carbocianinas , Eritrocitos , Colorantes Fluorescentes , Imagen por Resonancia Magnética , Imagen Óptica , Imagen por Resonancia Magnética/métodos , Eritrocitos/química , Colorantes Fluorescentes/química , Carbocianinas/química , Imagen Óptica/métodos , Humanos , Medios de Contraste/química , Verde de Indocianina/químicaRESUMEN
Performing spectroscopic measurements on biomolecules labeled with fluorescent probes is a powerful approach to locating the molecular behavior and dynamics of large systems at specific sites within their local environments. The indocarbocyanine dye Cy3 has emerged as one of the most commonly used chromophores. The incorporation of Cy3 dimers into DNA enhances experimental resolution owing to the spectral characteristics influenced by the geometric orientation of excitonically coupled monomeric units. Various theoretical models and simulations have been utilized to aid in the interpretation of the experimental spectra. In this study, we employ all-atom molecular dynamics simulations to study the structural dynamics of Cy3 dimers internally linked to the dsDNA backbone. We used quantum mechanical calculations to derive insights from both the linear absorption spectra and the circular dichroism data. Furthermore, we explore potential limitations within a commonly used force field for cyanine dyes. The molecular dynamics simulations suggest the presence of four possible Cy3 dimeric populations. The spectral simulations on the four populations show one of them to agree better with the experimental signatures, suggesting it to be the dominant population. The relative orientation of Cy3 in this population compares very well with previous predictions from the Holstein-Frenkel Hamiltonian model.
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Carbocianinas , ADN , Dimerización , Simulación de Dinámica Molecular , Teoría Cuántica , Carbocianinas/química , ADN/químicaRESUMEN
Hemicyanine dyes are an ideal structure for building near-infrared fluorescent probes due to their excellent emission wavelength properties and biocompatibility in biological imaging field. Developing a near-infrared fluorescent probe capable of detecting cysteine (Cys) was the aim of this study. A novel developed fluorescent probe P showed high selectivity and sensitivity to Cys in the presence of various analytes. The detection limit of P was found to be 0.329â µM. The MTT assay showed that the probe was essentially non-cytotoxic. Furthermore, the probe was successfully used as cysteine imaging in living cells and mice.
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Cisteína , Colorantes Fluorescentes , Cisteína/análisis , Cisteína/química , Colorantes Fluorescentes/química , Animales , Ratones , Humanos , Espectroscopía Infrarroja Corta/métodos , Límite de Detección , Carbocianinas/química , Espectrometría de Fluorescencia/métodos , Células HeLa , Imagen Óptica/métodosRESUMEN
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. SIGNIFICANCE: 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.
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Carbocianinas , Colorantes Fluorescentes , Proteínas de la Membrana , Colorantes Fluorescentes/química , Humanos , Carbocianinas/química , Proteínas de la Membrana/química , Proteínas de la Membrana/análisis , Proteínas de la Membrana/inmunología , Animales , Imagen Óptica , Anticuerpos/química , Anticuerpos/inmunología , RatonesRESUMEN
This study reports a fluorescent nanoprobe operated in fluorescence turn-on mode for simultaneously sensing and imaging intracellular GSH and ATP. By using maleimide-derivatives as the ligand, the bimetallic nanoscale metal-organic framework (NMOF) Cu-Mi-UiO-66 has been synthesized for the first time using a straightforward one-step solvothermal approach, serving as a GSH recognition moiety. Subsequently, a Cy5-labeled ATP aptamer was assembled onto Cu-Mi-UiO-66 via strong coordination between phosphate and zirconium, π-π stacking and electrostatic adsorption to develop the dual-responsive fluorescence nanoprobe Cu-Mi-UiO-66/aptamer. Due to the photoinduced electron transfer (PET) effect between maleimide groups and the benzene ring of the ligand and the charge transfer between Cy5 and the Zr(IV)/Cu(II) bimetal center of the NMOF, the Cu-Mi-UiO-66/aptamer exhibits a fluorescence turn-off status. The Michael addition reaction between the thiol group of GSH and the maleimide on the NMOF skeleton results in turning on of the blue fluorescence of Cu-Mi-UiO-66. Meanwhile, upon specific interaction with ATP, the aptamer changes into internal loop structures and detaches from Cu-Mi-UiO-66, resulting in turning on of the red fluorescence of Cy5. The nanoprobe demonstrated an excellent sensing performance with a good linear range (GSH, 5.0-450.0 µM; ATP, 1.0-50.0 µM) and a low detection limit (GSH, 2.17 µM; ATP, 0.635 µM). More importantly, the Cu-Mi-UiO-66/aptamer exhibits good performance for tracing intracellular concentration variations of GSH and ATP in living HepG2 cells under different stimulations. This study highlights the potential of NMOFs for multiplexed analysis and provides a valuable tool for tumor microenvironment research and early cancer diagnosis.
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Adenosina Trifosfato , Cobre , Colorantes Fluorescentes , Glutatión , Estructuras Metalorgánicas , Glutatión/análisis , Glutatión/química , Adenosina Trifosfato/análisis , Adenosina Trifosfato/química , Adenosina Trifosfato/metabolismo , Humanos , Colorantes Fluorescentes/química , Cobre/química , Estructuras Metalorgánicas/química , Aptámeros de Nucleótidos/química , Circonio/química , Carbocianinas/química , Espectrometría de Fluorescencia , Ácidos FtálicosRESUMEN
Fluorogenic dimers with polarity-sensitive folding are powerful probes for live-cell bioimaging. They switch on their fluorescence only after interacting with their targets, thus leading to a high signal-to-noise ratio in wash-free bioimaging. We previously reported the first near-infrared fluorogenic dimers derived from cyanine 5.5 dyes for the optical detection of G protein-coupled receptors. Owing to their hydrophobic character, these dimers are prone to form nonspecific interactions with proteins such as albumin and with the lipid bilayer of the cell membrane resulting in a residual background fluorescence in complex biological media. Herein, we report the rational design of new fluorogenic dimers derived from cyanine 5. By modulating the chemical structure of the cyanine units, we discovered that the two asymmetric cyanine 5.25 dyes were able to form intramolecular H-aggregates and self-quenched in aqueous media. Moreover, the resulting original dimeric probes enabled a significant reduction of the nonspecific interactions with bovine serum albumin and lipid bilayers compared with the first generation of cyanine 5.5 dimers. Finally, the optimized asymmetric fluorogenic dimer was grafted to carbetocin for the specific imaging of the oxytocin receptor under no-wash conditions directly in cell culture media, notably improving the signal-to-background ratio compared with the previous generation of cyanine 5.5 dimers.
Asunto(s)
Carbocianinas , Colorantes Fluorescentes , Membrana Dobles de Lípidos , Receptores Acoplados a Proteínas G , Albúmina Sérica Bovina , Carbocianinas/química , Colorantes Fluorescentes/química , Membrana Dobles de Lípidos/química , Membrana Dobles de Lípidos/metabolismo , Humanos , Albúmina Sérica Bovina/química , Animales , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/química , Dimerización , Bovinos , Diseño de FármacosRESUMEN
We propose a novel strategy for tailoring the structure of fluorescent molecules to achieve emission at the tail end of the NIR-II window. The favorable spectroscopic properties and low cytotoxicity of YNs make them powerful tools for bioimaging. Notably, YN-4 exhibits a brightness 2.5 times greater than YN-3, 6 times that of IR-783, and 5 times that of ICG. This enhanced brightness enabled high-resolution imaging of mouse thoracic and abdominal cavities, tumor vasculature, and real-time monitoring of gastrointestinal motility using YN-4. Furthermore, covalent grafting of glucose onto the YN-Glu scaffold significantly improved tumor-targeting capability and facilitated tracking of glucose metabolism. This work aims to extend the application of fluorescent molecule imaging beyond the NIR-IIa window.
Asunto(s)
Colorantes Fluorescentes , Indoles , Animales , Ratones , Indoles/química , Colorantes Fluorescentes/química , Humanos , Espectroscopía Infrarroja Corta/métodos , Imagen Óptica , Carbocianinas/química , Línea Celular Tumoral , Glucosa/metabolismo , Glucosa/químicaRESUMEN
Hypochlorite (ClO-) is recognized as a bioactive substance that plays a crucial role in various physiological and pathological processes. The increase of ClO- content in cells is a key factor in the early atherosclerosis lesions, which are closely linked to cardiovascular and cerebrovascular diseases. Therefore, the development of an efficient and sensitive method for detecting hypochlorite in tap water, serum, and living cells, including animal model in vivo is of paramount importance. In this study, a novel fluorescent probe (Cy-F) based on the cyanine group was designed for the specific detection of ClO-, demonstrating exceptional selectivity, high sensitivity, and rapid response. The probe successfully detected ClO- in tap water and serum with a limit of detection (LOD) of 2.93 × 10-7 M, showcasing excellent anti-interference capabilities. Notably, the probe exhibited good biocompatibility, low biological toxicity, and proved effective for detecting and analyzing ClO- in live cells and zebrafish. This newly developed probe offers a promising approach and valuable tool for detecting ClO- with biosafety considerations, paving the way for the design of functional probes tailored for future biomedical applications.
Asunto(s)
Carbocianinas , Colorantes Fluorescentes , Ácido Hipocloroso , Límite de Detección , Pez Cebra , Ácido Hipocloroso/análisis , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Animales , Humanos , Carbocianinas/química , Espectrometría de Fluorescencia , Ratones , Células RAW 264.7RESUMEN
Single-molecule localization methods have been popularly exploited to obtain super-resolved images of biological structures. However, the low blinking frequency of randomly switching emission states of individual fluorophores greatly limits the imaging speed of single-molecule localization microscopy (SMLM). Here we present an ultrafast SMLM technique exploiting spontaneous fluorescence blinking of cyanine dye aggregates confined to DNA framework nanostructures. The DNA template guides the formation of static excimer aggregates as a "light-harvesting nanoantenna", whereas intermolecular excitation energy transfer (EET) between static excimers causes collective ultrafast fluorescence blinking of fluorophore aggregates. This DNA framework-based strategy enables the imaging of DNA nanostructures with 12.5-fold improvement in speed compared to conventional SMLM. Further, we demonstrate the use of this strategy to track the movement of super-resolved DNA nanostructures for over 20 min in a microfluidic system. Thus, this ultrafast SMLM holds great potential for revealing the dynamic processes of biomacromolecules in living cells.