Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 182
Filtrar
1.
Adv Mater ; : e2407262, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39279542

RESUMEN

Molecular magnetic resonance imaging (MRI) combines chemistry, chemical biology, and imaging techniques to track molecular events non-invasively. Quantitative molecular MRI aims to provide meaningful, reproducible numerical measurements of molecular processes or biochemical targets within the body. In this review, the classifications of molecular MRI probes based on their signal-generating mechanism and functionality are first described. From there, the primary considerations for in vitro characterization and in vivo validation of molecular MRI probes, including how to avoid pitfalls and biases are discussed. Then, recommendations on imaging acquisition protocols and analysis methods to establish quantitative relationships between MRI signal change induced by the probes and the molecular processes of interest are provided. Finally, several representative case studies are highlighted that incorporate these features. Quantitative molecular MRI is a multidisciplinary research area incorporating expertise in chemical biology, inorganic chemistry, molecular probes, imaging physics, drug development, pathobiology, and medicine. The purpose of this review is to provide guidance to chemists developing MR imaging probes and methods in terms of in vitro and in vivo validation to accelerate the translation of these new quantitative tools for non-invasive imaging of biological processes.

2.
Front Oncol ; 14: 1442601, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39281380

RESUMEN

Purpose: Fibroblast activation protein (FAP) is highly expressed in the mesenchyme of most malignant epithelial tumors, while its expression is low in normal tissues. FAP inhibitors (FAPIs) bind specifically to FAP and are used for tumor-targeted diagnosis and therapy. The aim of this study was to radiosynthesize a novel molecular probe 131I-FAPI and evaluate its in-vitro targeting and biological characteristics. Methods: The structurally modified FAPI was labelled with 131I through the chloramine-T method. The radiolabeling rate was then detected by thin-layer chromatography (TLC). The stability of 131I-FAPI was determined at PBS (room temperature) and serum (37°C). Its hydrophilicity was calculated by measuring its lipid-water partition coefficient. Pancreatic cancer PANC-1 cell line and glioma U87 cell line were cultured in vitro. Cell uptake assay was used to show the binding ability of 131I-FAPI. The CCK-8 assay was used to calculate the inhibitory effects of 131I-FAPI at different time points (4h, 8h, 12h, 24h, 48h) after comparing with the 131I and FAPI. The before-and-after-24h scratch areas of the two cells were determined in order to verify the effect of 131I-FAPI on the migration ability of the cells. Results: The radiolabeling rate was (84.9 ± 1.02) %. The radiochemical purity of 131I-FAPI remained over 80% in both 25°C PBS and 37°C serum. The value of the lipid-water partition coefficient was -0.869 ± 0.025, indicating the hydrophilic of the probe. The cellular uptake assay showed that U87 cells had a specific binding capacity for 131I-FAPI. In cell inhibition assays, the inhibitory effect of 131I-FAPI on U87 cells increased with time. The results of cell scratch assay showed that 131I-FAPI had the strongest inhibitory effect on the migratory ability of U87 cells compared with 131I and FAPI (P<0.001). Conclusion: 131I-FAPI was synthesized with good in-vitro stability and hydrophilic properties. It can be specifically bound by U87 cells. The proliferation and migration of U87 cells can be effectively inhibited. 131I-FAPI is promising to become a therapeutic probe.

3.
Heliyon ; 10(15): e35502, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39170113

RESUMEN

To evaluate the efficacy of the 18F-AlF-NOTA-RGD2 positron emission tomography (PET)/computed tomography (CT) molecular probe for the noninvasive staging of liver fibrosis in mini pigs, a potential alternative to invasive diagnostic methods was revealed. This study used 18F-AlF-NOTA-RGD2 PET/CT imaging of mini pigs to assess liver fibrosis. The methods included synthesis and quality control of the molecular probe, establishment of an animal model of liver fibrosis, blood serum enzymatic tests, histopathological examination, PET/CT imaging, collagen content and expression, and mitochondrial reserve function assessment. The 18F-AlF-NOTA-RGD2 PET/CT molecular probe effectively differentiated various stages of liver fibrosis in mini pigs. Blood serum enzymatic tests revealed distinct stages of liver fibrosis, revealing significant increases in AST, ALT, TBIL, and DBIL levels as fibrosis advanced. Notably, ALT levels increased markedly in severe fibrosis patients. A gradual increase in collagen deposition and increasing α-SMA RNA expression and protein levels effectively differentiated between mild and severe fibrosis stages. Pathological examinations and Sirius Red staining confirmed these findings, highlighting substantial increases in collagen accumulation. PET/CT imaging results aligned with histopathological findings, showing that increased radiotracer uptake correlated with fibrosis severity. Assessments of mitochondrial function revealed a decrease in total liver glutathione content and mitochondrial reserve capacity, especially in patients with severe fibrosis. The 18F-AlF-NOTA-RGD2 PET/CT molecular probe is a promising tool for the noninvasive assessment of liver fibrosis, offering potential benefits over traditional diagnostic methods in hepatology.

4.
ACS Nano ; 18(29): 18910-18921, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39001856

RESUMEN

Granzyme B is an immune-related biomarker that closely correlates with cytotoxic T lymphocytes (CTLs), and hence detecting the expression level of granzyme B can provide a dependable scheme for clinical immune response assessment. In this study, two positron emission tomography (PET) probes [18F]SF-M-14 and [18F]SF-H-14 targeting granzyme B are designed based on the intramolecular cyclization scaffold SF. [18F]SF-M-14 and [18F]SF-H-14 can respond to granzyme B and glutathione (GSH) to conduct intramolecular cyclization and self-assemble into nanoaggregates to enhance the retention of probe at the target site. Both probes are prepared with high radiochemical purity (>98%) and high stability in PBS and mouse serum. In 4T1 cells cocultured with T lymphocytes, [18F]SF-M-14 and [18F]SF-H-14 reach the maximum uptake of 6.71 ± 0.29 and 3.47 ± 0.09% ID/mg at 0.5 h, respectively, but they remain below 1.95 ± 0.22 and 1.47 ± 0.21% ID/mg in 4T1 cells without coculture of T lymphocytes. In vivo PET imaging shows that the tumor uptake in 4T1-tumor-bearing mice after immunotherapy is significantly higher (3.5 times) than that in the untreated group. The maximum tumor uptake of [18F]SF-M-14 and [18F]SF-H-14 in the mice treated with BEC was 4.08 ± 0.16 and 3.43 ± 0.12% ID/g, respectively, while that in the untreated mice was 1.04 ± 0.79 and 1.41 ± 0.11% ID/g, respectively. These results indicate that both probes have great potential in the early evaluation of clinical immunotherapy efficacy.


Asunto(s)
Granzimas , Inmunoterapia , Tomografía de Emisión de Positrones , Animales , Granzimas/metabolismo , Ratones , Femenino , Ratones Endogámicos BALB C , Línea Celular Tumoral , Radiofármacos/química , Radioisótopos de Flúor/química , Humanos
5.
Methods Mol Biol ; 2830: 51-62, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38977567

RESUMEN

Seed germination of a parasitic plant Striga hermonthica is elicited by strigolactones which are exuded from roots of host plants. Here, we describe a high-throughput germination assay and a method for visualizing in vivo strigolactone receptor functions with a fluorogenic probe.


Asunto(s)
Germinación , Lactonas , Semillas , Striga , Striga/fisiología , Striga/crecimiento & desarrollo , Striga/efectos de los fármacos , Semillas/crecimiento & desarrollo , Lactonas/metabolismo , Lactonas/farmacología , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/parasitología , Sondas Moleculares/química , Colorantes Fluorescentes/química
6.
Anal Chim Acta ; 1317: 342911, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39030011

RESUMEN

Natural products-based screening of active ingredients and their interactions with target proteins is an important ways to discover new drugs. Assessing the binding capacity of target proteins, particularly when multiple components are involved, presents a significant challenge for sensors. As far as we know, there is currently no sensor that can accomplish high-throughput quantitative analysis of natural product-target protein binding capacity based on Raman spectroscopy. In this study, a novel sensor model has been developed for the quantitative analysis of binding capacity based on Surface-Enhanced Raman Spectroscopy (SERS) and Photocrosslinked Molecular Probe (PCMP) technology. This sensor, named SERS-PCMP, leverages the high throughput of molecular probe technology to investigate the active ingredients in natural products, along with the application of SERS labelling technology for target proteins. Thus it significantly improves the efficiency and accuracy of target protein identification. Based on the novel strategy, quantitative analysis of the binding capacity of 20 components from Shenqi Jiangtang Granules (SJG) to α-Glucosidase were completed. Ultimately, the binding capacity of these active ingredients was ranked based on the detected Raman Intensity. The compounds with higher binding capacity were Astragaloside IV (Intensity, 138.17), Ginsenoside Rh2 (Intensity, 87.46), Ginsenoside Rg3 (Intensity, 73.92) and Ginsenoside Rh1 (Intensity, 64.37), which all exceeded the binding capacity of the positive drug Acarbose (Intensity, 28.75). Furthermore, this strategy also performed a high detection sensitivity. The limit of detection for the enzyme using 0.1 mg of molecular probe magnetic nanoparticles (MP MNPs) was determined to be no less than 0.375 µg/mL. SERS-PCMP sensor integrating SERS labeling and photocrosslinked molecular probes which offers a fresh perspective for future drug discovery studies. Such as high-throughput drug screening and the exploration of small molecule-target protein interactions in vitro.


Asunto(s)
Productos Biológicos , Sondas Moleculares , Espectrometría Raman , Espectrometría Raman/métodos , Productos Biológicos/química , Productos Biológicos/análisis , Sondas Moleculares/química , alfa-Glucosidasas/metabolismo , alfa-Glucosidasas/química , Unión Proteica , Procesos Fotoquímicos , Reactivos de Enlaces Cruzados/química , Plata/química
7.
Angew Chem Int Ed Engl ; : e202407308, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38995157

RESUMEN

The intrinsic correlation between depression and serotonin (5-HT) is a highly debated topic, with significant implications for the diagnosis, treatment, and advancement of drugs targeting neurological disorders. To address this important question, it is of utmost priority to understand the action mechanism of serotonin in depression through fluorescence imaging studies. However, the development of efficient molecular probes for serotonin is hindered by the lack of responsive sites with high selectivity for serotonin at the present time. Herein, we developed the first highly selective serotonin responsive site, 3-mercaptopropionate, utilizing thiol-ene click cascade nucleophilic reactions. The novel responsive site was then employed to construct the powerful molecular probe SJ-5-HT for imaging the serotonin level changes in the depression cells and brain tissues. Importantly, the imaging studies reveal that the level of serotonin in patients with depression may not be the primary factor, while the ability of neurons in patients with depression to release serotonin appears to be more critical. Additionally, this serotonin release capability correlates strongly with the levels of mTOR (intracellular mammalian target of rapamycin). These discoveries could offer valuable insights into the molecular mechanisms underpinning depression and furnish mTOR as a novel direction for the advancement of antidepressant therapies.

8.
Angew Chem Int Ed Engl ; 63(31): e202404093, 2024 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-38727540

RESUMEN

Accurate visualization of tumor microenvironment is of great significance for personalized medicine. Here, we develop a near-infrared (NIR) fluorescence/photoacoustic (FL/PA) dual-mode molecular probe (denoted as NIR-CE) for distinguishing tumors based on carboxylesterase (CE) level by an analyte-induced molecular transformation (AIMT) strategy. The recognition moiety for CE activity is the acetyl unit of NIR-CE, generating the pre-product, NIR-CE-OH, which undergoes spontaneous hydrogen atom exchange between the nitrogen atoms in the indole group and the phenol hydroxyl group, eventually transforming into NIR-CE-H. In cellular experiments and in vivo blind studies, the human hepatoma cells and tumors with high level of CE were successfully distinguished by both NIR FL and PA imaging. Our findings provide a new molecular imaging strategy for personalized treatment guidance.


Asunto(s)
Carboxilesterasa , Medicina de Precisión , Humanos , Carboxilesterasa/metabolismo , Sondas Moleculares/química , Colorantes Fluorescentes/química , Imagen Óptica , Animales
9.
Nucl Med Biol ; 134-135: 108915, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38723361

RESUMEN

BACKGROUND: The polyamine transporter system (PTS), which renders it a promising target for tumor therapy and imaging applications, facilitates the transmembrane transport of polyamines. We reported a novel derivative of spermine labeled with gallium-68 ([68Ga]Ga-NOTA-Spermine) for the imaging of the PTS in mouse models of tumor. RESULTS: The radiochemical yield of [68Ga]Ga-NOTA-Spermine was determined to be 64-69 %, demonstrating exceptional stability and radiochemical purity (>98 %). Cellular uptake experiments revealed that A549 cells exhibited peak uptake of [68Ga]Ga-NOTA-Spermine at 90 min (15.4 % ± 0.68 %). Biodistribution analysis demonstrated significant accumulation of [68Ga]Ga-NOTA-Spermine in kidneys and liver, while exhibiting low uptake levels in muscle, brain, and bones. Furthermore, Micro-PET/CT scans conducted on A549 tumor-bearing mouse models indicated substantial uptake of [68Ga]Ga-NOTA-Spermine, with maximum tumor/muscle (T/M) ratios reaching 3.71. CONCLUSION: These results suggest that [68Ga]Ga-NOTA-Spermine holds potential as a PET imaging agent for tumors with high levels of PTS.


Asunto(s)
Radioisótopos de Galio , Espermina , Animales , Radioisótopos de Galio/química , Ratones , Espermina/análogos & derivados , Espermina/química , Espermina/síntesis química , Espermina/farmacocinética , Humanos , Distribución Tisular , Marcaje Isotópico , Técnicas de Química Sintética , Tomografía de Emisión de Positrones/métodos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Células A549 , Radioquímica , Transporte Biológico , Compuestos Heterocíclicos con 1 Anillo
10.
J Fluoresc ; 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38700636

RESUMEN

A great deal of effort has been put into developing a novel and cost-effective molecular probe for selective and sensitive recognition of trace amounts of water in organic solvents due to their tremendous advantages in industrial, pharmaceutical, and laboratory-scale chemistry. Herein, a cost-effective chemosensor L has been designed and studied for the detection of trace amounts of water. The addition of water to the DMSO solution of L exhibited an enhancement of fluorescence emission at 460 nm along with a color change from green to colorless. The spectral and color changes occurred due to the self-aggregation of L. The interaction between water and L was performed by dynamic light scattering (DLS), scanning electron microscope (SEM) and finally complemented by quantum mechanical calculation. The detection limit was found to be 0.0093 wt% in DMSO. The L also exhibits a fast visual response and is effectively applied to detect trace amounts of moisture in various food materials (salt, sugar, wheat and honey) and building materials (cement, fly ash, limestone and sand).

11.
ACS Appl Mater Interfaces ; 16(14): 17253-17266, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38557012

RESUMEN

Extending molecular imaging into the shortwave-infrared (SWIR, 900-1400 nm) region provides deep tissue visualization of biomolecules in the living system resulting from the low tissue autofluorescence and scattering. Looking at the Food and Drug Administration-approved and clinical trial near-infrared (NIR) probes, only indocyanine green (ICG) and its analogues have been approved for biomedical applications. Excitation wavelength less than 800 nm limits these probes from deep tissue penetration and noninvasive fluorescence imaging. Herein, we present the synthesis of ICG-based π-conjugation-extended cyanine dyes, ICG-C9 and ICG-C11 as biocompatible, and water-soluble SWIR-emitting probes with emission wavelengths of 922 and 1010 nm in water, respectively. Also, ICG-, ICG-C9-, and ICG-C11-based fluorescent labeling agents have been synthesized for the development of SWIR molecular imaging probes. Using the fluorescence of ICG, ICG-C9, and ICG-C11, we demonstrate three-color SWIR fluorescence imaging of breast tumors by visualizing surface receptors (EGFR and HER2) and tumor vasculature in living mice. Furthermore, we demonstrate two-color SWIR fluorescence imaging of breast tumor apoptosis using an ICG-conjugated anticancer drug, Kadcyla and ICG-C9 or ICG-C11-conjugated annexin V. Finally, we show long-term (38 days) SWIR fluorescence imaging of breast tumor shrinkage induced by Kadcyla. This study provides a general strategy for multiplexed fluorescence molecular imaging with biocompatible and water-soluble SWIR-emitting cyanine probes.


Asunto(s)
Neoplasias de la Mama , Colorantes Fluorescentes , Animales , Ratones , Humanos , Femenino , Ado-Trastuzumab Emtansina , Verde de Indocianina , Imagen Molecular , Imagen Óptica/métodos , Neoplasias de la Mama/diagnóstico por imagen
12.
Talanta ; 272: 125770, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38340393

RESUMEN

Twisted intramolecular charge transfer (TICT) is a fluorescence quenching mechanism that occurs in donor-acceptor (D‒A) molecules. Chemical engineering research into TICT regulation over the past 50 years has primarily focused on manipulating steric factors by introducing alkyl groups at the D-A junction (pre-twisting). Herein, we report a significant advance in TICT-based probes through the introducing of H-bond as an efficient strategy for suppressing TICT. Accordingly, ortho-Cl installation in the N-phenylpyrazine-2-carboxamide (PPC) platform can achieve complete reversal from the quenching mode to the light-up mode. This specific H-bonding (N-H⋯Cl) effectively blocks N-C(Ar) bond rotation, leading to fluorescence-ON. This suggested that TICT inhibition may be involved. Therefore, in a sharp contrast to the general nature of the pre-twisting method in rotor molecules, which involves incorporating steric hindrance at either the donor or acceptor moiety to enhance intramolecular rotation (promotion TICT), the ortho-H bonding strategy completely freezes D‒A bond twisting (suppression TICT), resulting in improved fluorescent intensity. Furthermore, the fluorophores were evaluated for Hg2+ detection and in vivo bio-imaging. Notably, Hg-complexation induced another fluorescence inversion (OFF-ON) by imposing spatial constraints on twisting freedom in 3,4-Cl-PPC. Taken together, this work provides a valid and generalizable tactic for the development of high-performance sensing fluorophores through inhibition of TICT.

13.
Biosens Bioelectron ; 251: 116125, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38359668

RESUMEN

Iron is an essential element that plays critical roles in many biological/metabolic processes, ranging from oxygen transport, mitochondrial respiration, to host defense and cell signaling. Maintaining an appropriate iron level in the body is vital to the human health. Iron deficiency or overload can cause life-threatening conditions. Thus, developing a new, rapid, cost-effective, and easy to use method for iron detection is significant not only for environmental monitoring but also for disease prevention. In this study, we report an innovative Fe3+ detection strategy by using both a ligand probe and an engineered nanopore with two binding sites. In our design, one binding site of the nanopore has a strong interaction with the ligand probe, while the other is more selective toward interfering species. Based on the difference in the number of ligand DTPMPA events in the absence and presence of ferric ions, micromolar concentrations of Fe3+ could be detected within minutes. Our method is selective: micromolar concentrations of Mg2+, Ca2+, Cd2+, Zn2+, Ni2+, Co2+, Mn2+, and Cu2+ would not interfere with the detection of ferric ions. Furthermore, Cu2+, Ni2+, Co2+, Zn2+, and Mn2+ produced current blockage events with quite different signatures from each other, enabling their simultaneous detection. In addition, simulated water and serum samples were successfully analyzed. The nanopore sensing strategy developed in this work should find useful application in the development of stochastic sensors for other substances, especially in situations where multi-analyte concurrent detection is desired.


Asunto(s)
Técnicas Biosensibles , Nanoporos , Humanos , Ligandos , Técnicas Biosensibles/métodos , Iones/química , Hierro
14.
Cell Calcium ; 117: 102834, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38006628

RESUMEN

Many physiological functions, such as cell differentiation, proliferation, muscle contraction, neurotransmission and fertilisation, are regulated by changes of Ca2+ levels. The major Ca2+ store in cells is the endoplasmic reticulum (ER). Certain cellular processes induce ER store depletion, e.g. by activating IP3 receptors, that in turn induces a store refilling process known as store-operated calcium entry (SOCE). This refilling process entails protein-protein interactions between Ca2+ sensing stromal interaction molecules (STIM) in the ER membrane and Orai proteins in the plasma membrane. Fully assembled STIM/Orai complexes then form highly selective Ca2+ channels called Ca2+ release-activated Ca2+ Channels (CRAC) through which Ca2+ ions flow into the cytosol and subsequently are pumped into the ER by the sarcoplasmic/endoplasmic reticulum calcium ATPase (SERCA). Abnormal SOCE has been associated with numerous human diseases and cancers, and therefore key players STIM and Orai have attracted significant therapeutic interest. Several potent experimental and clinical candidate compounds have been developed and have helped to study SOCE in various cell types. We have synthesized multiple novel small-molecule probes based on the known SOCE inhibitor GSK-7975A. Here we present GSK-7975A derivatives, which feature photo-caging, photo-crosslinking, biotin and clickable moieties, and also contain deuterium labels. Evaluation of these GSK-7975A probes using a fluorometric imaging plate reader (FLIPR)-Tetra-based Ca2+ imaging assay showed that most synthetic modifications did not have a detrimental impact on the SOCE inhibitory activity. The photo-caged GSK-7975A was also used in patch-clamp electrophysiology experiments. In summary, we have developed a number of active, GSK-7975A-based molecular probes that have interesting properties and therefore are useful experimental tools to study SOCE in various cells and settings.


Asunto(s)
Benzamidas , Señalización del Calcio , Calcio , Pirazoles , Humanos , Señalización del Calcio/fisiología , Calcio/metabolismo , Molécula de Interacción Estromal 1/metabolismo , Canales de Calcio/metabolismo , Proteína ORAI1/metabolismo
15.
ACS Appl Bio Mater ; 7(1): 362-368, 2024 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-38150719

RESUMEN

Conditionally activated molecule release in live cells would provide spatiotemporal control for the study and intervention of biological processes, e.g., bioactive molecule monitoring and controlled drug release. Mitochondria are the main sites of reactive oxygen species (ROS) production in cells. Here, we report an ROS-triggered molecule release strategy in mitochondria. A molecule IRTO with dual targeting groups was designed by covalently linking IR-780 (a mitochondrial targeted heptamethine cyanine) and 4-aminobutyl-thiazole orange (NH2-TO, a nuclear dye). IRTO diffused into live cells and first accumulated in mitochondria. As the cyanine moiety reacted with mitochondrial ROS directly or with the help of mitochondrial cytochromes, NH2-TO was released, escaped from mitochondria, and finally located in the nucleus. This process could be visualized by fluorescent imaging, i.e., red fluorescence (from the cyanine moiety of IRTO) first located in mitochondria, and green fluorescence (from NH2-TO) appeared and gradually enhanced in the nucleus with the increase of incubation time. The addition of H2O2 or lipopolysaccharide (LPS, an ROS accelerator) could accelerate the release of NH2-TO, whereas N-acetyl-l-cysteine (NAC, an ROS inhibitor) and mitoquinone mesylate (MitoQ, a mitochondrial ROS scavenger) could obviously decrease the release of NH2-TO. These results suggest that IRTO could serve as a fluorescent probe for monitoring ROS in mitochondria and that IR-780 might be a promising endogenous ROS-triggered molecule release platform.


Asunto(s)
Peróxido de Hidrógeno , Mitocondrias , Especies Reactivas de Oxígeno , Colorantes Fluorescentes , Acetilcisteína/farmacología
16.
Front Physiol ; 14: 1257739, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37936577

RESUMEN

Introduction: MitoView 633, a far-red fluorescent dye, exhibits the ability to accumulate within mitochondria in a membrane potential-dependent manner, as described by the Nernst equation. This characteristic renders it a promising candidate for bioenergetics studies, particularly as a robust indicator of mitochondrial membrane potential (DYm). Despite its great potential, its utility in live cell imaging has not been well characterized. Methods: This study seeks to characterize the spectral properties of MitoView 633 in live cells and evaluate its mitochondrial staining, resistance to photobleaching, and dynamics during DYm depolarization. The co-staining and imaging of MitoView 633 with other fluorophores such as MitoSOX Red and Fluo-4 AM were also examined in cardiomyocytes using confocal microscopy. Results and Discussion: Spectrum analysis showed that MitoView 633 emission could be detected at 660 ± 50 nm, and exhibited superior thermal stability compared to tetramethylrhodamine methyl ester (TMRM), a commonly used DYm indicator, which emits at 605 ± 25 nm. Confocal imaging unequivocally illustrated MitoView 633's specific localization within the mitochondrial matrix, corroborated by its colocalization with MitoTracker Green, a well-established mitochondrial marker. Furthermore, our investigation revealed that MitoView 633 exhibited minimal photobleaching at the recommended in vitro concentrations. Additionally, the dynamics of MitoView 633 fluoresce during carbonyl cyanide-p-trifluoromethoxyphenylhydrazone (FCCP, a mitochondrial uncoupler)-induced DYm depolarization mirrored that of TMRM. Importantly, MitoView 633 demonstrated compatibility with co-staining alongside MitoSOX Red and Fluo-4 AM, enabling concurrent monitoring of DYm, mitochondrial ROS, and cytosolic Ca2+ in intact cells. Conclusion: These findings collectively underscore MitoView 633 as a superb molecular probe for the singular or combined assessment of DYm and other indicators in live cell imaging applications.

17.
Ecotoxicol Environ Saf ; 267: 115671, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37951093

RESUMEN

Eutrophication remains one of the most challenging environmental problems, and microcystin-leucine-arginine (MC-LR) produced in eutrophic waters would cause serious ecological risks. However, the traditional assessment methods of trophic status, such as water quality index (WQI) and trophic status index (TSI), could not directly reflect the existence or concentration of MC-LR in water. Moreover, traditional MC-LR detection methods are costly and time-consuming. Therefore, it remains a challenge to develop a method that can simply and quickly reflect the level of MC-LR. Herein, a novel probe with specific response to MC-LR was proposed to assess the distribution characteristics of MC-LR in water bodies. By combining the response signal of the probe with the filtered water sample and the water quality parameters, a more accurate assessment tool for MC-LR was obtained. This probe can specifically respond to MC-LR in aqueous solution, and its fluorescence signal is enhanced with the increase of MC-LR concentration. More importantly, the fluorescent signal of the probe showed a significant positive correlation with MC-LR concentration in water samples. This visualization tool has practical application potential for the preliminary assessment of MC-LR in eutrophic waters.


Asunto(s)
Lagos , Estado Nutricional , Retroalimentación , Fluorescencia , Arginina
18.
Adv Sci (Weinh) ; 10(33): e2303926, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37870188

RESUMEN

The hydroxyl radical (•OH) is shown to play a crucial role in the occurrence and progression of acute kidney injury (AKI). Therefore, the development of a robust •OH probe holds great promise for the early diagnosis of AKI, high-throughput screening (HTS) of natural protectants, and elucidating the molecular mechanism of intervention in AKI. Herein, the design and synthesis of an activatable fluorescent/photoacoustic (PA) probe (CDIA) for sensitive and selective imaging of •OH in AKI is reported. CDIA has near-infrared fluorescence/PA channels and fast activation kinetics, enabling the detection of the onset of •OH in an AKI model. The positive detection time of 12 h using this probe is superior to the 48-hour detection time for typical clinical assays, such as blood urea nitrogen and serum creatinine detection. Furthermore, a method is established using CDIA for HTS of natural •OH inhibitors from herbal medicines. Puerarin is screened out by activating the Sirt1/Nrf2/Keap1 signaling pathway to protect renal cells in AKI. Overall, this work provides a versatile and dual-mode tool for illuminating the •OH-related pathological process in AKI and screening additional compounds to prevent and treat AKI.


Asunto(s)
Lesión Renal Aguda , Colorantes Fluorescentes , Humanos , Radical Hidroxilo/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Ensayos Analíticos de Alto Rendimiento , Iluminación , Factor 2 Relacionado con NF-E2/metabolismo , Lesión Renal Aguda/diagnóstico , Lesión Renal Aguda/metabolismo , Riñón/metabolismo
19.
Sensors (Basel) ; 23(18)2023 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-37765882

RESUMEN

In this study, we have undertaken the development of two fluorescent sensors based on calixarene compounds for the purpose of detecting cesium in water. By introducing the sulfonate functional groups, we have considerably improved the water solubility of sensors, enabling complete dissolution of products in aqueous media and direct analysis of polluted water samples. Through rigorous experiments, we have demonstrated that the complexation of Cs+ ions with sensors 1 and 2 in water leads to a remarkable enhancement of fluorescence. This fluorescence enhancement serves as a reliable indication of cesium presence and allows for sensitive detection. To further advance the practical application of our sensors, we have successfully integrated calixarene sensors 1 and 2 into a microfluidic sensor chip. This integration has enabled real-time, on-line measurements and has resulted in the development of a portable detection device capable of detecting cesium ions in water samples at parts per billion (ppb) levels. This device holds great promise for environmental monitoring and assessment, providing a convenient and efficient solution for cesium detection. Our work represents a significant advancement in the field of cesium detection, displaying the efficacy of calixarene-based fluorescent sensors and their integration into microfluidic systems. The enhanced water solubility, fluorescence response, and portability of our detection device offers tremendous potential for applications in environmental monitoring, water quality assessment, and emergency response scenarios where rapid and accurate cesium detection is crucial.

20.
Molecules ; 28(17)2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37687230

RESUMEN

A versatile mono-Schiff compound consisting of o-aminobenzene-hydroxyjulolidine (ABJ-MS) has been easily synthesized using a one-step reaction. ABJ-MS displays four diverse fluorescence responses to the addition of Zn2+/Al3+/Fe3+/Ag+, with the maximum fluorescence emission at 530 nm undergoing a hypsochromic shift to 502/490/440/430 nm, synchronously with the discriminating fluorescence enhancement being 10.6/22.8/2.6/7.1-fold, respectively. However, the addition of Cu2+ into ABJ-MS leads to an opposite behavior, namely, fluorescence quenching. Meanwhile, ABJ-MS also displays distinct absorption changes after adding these five metal ions due to different binding affinities between them and ABJ-MS, which gives ABJ-MS quite a versatile detecting nature for Cu2+/Zn2+/Al3+/Fe3+/Ag+. Moreover, ABJ-MS can mimic a series of versatile AND/OR/INH-consisting logic circuits on the basis of the Cu2+/Zn2+/Al3+/Fe3+/Ag+-mediated diverse optical responses. These will endow the smart ABJ-MS molecule and potential applications in the multi-analysis chemosensory and molecular logic material fields.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA