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We present super-resolution microscopy of isolated functional mitochondria, enabling real-time studies of structure and function (voltages) in response to pharmacological manipulation. Changes in mitochondrial membrane potential as a function of time and position can be imaged in different metabolic states (not possible in whole cells), created by the addition of substrates and inhibitors of the electron transport chain, enabled by the isolation of vital mitochondria. By careful analysis of structure dyes and voltage dyes (lipophilic cations), we demonstrate that most of the fluorescent signal seen from voltage dyes is due to membrane bound dyes, and develop a model for the membrane potential dependence of the fluorescence contrast for the case of super-resolution imaging, and how it relates to membrane potential. This permits direct analysis of mitochondrial structure and function (voltage) of isolated, individual mitochondria as well as submitochondrial structures in the functional, intact state, a major advance in super-resolution studies of living organelles.

Adsorption, a crucial method for removing dyes from wastewater, has been extensively studied in the context of eliminating Acridine Orange (AO), a cationic dye, from contaminated water. This review underscores the environmental risks posed by AO, given its high toxicity, and delves into various adsorption techniques developed to eliminate it from water. It covers works on AO removal published from 1981 to April 2024, highlighting the effectiveness of different adsorbents, including natural, synthetic, composite, and nanomaterials, under varying conditions like pH, initial dye concentrations, temperature, and adsorbent dosages. Most studies on adsorption isotherms, kinetics, and thermodynamics have yielded favorable results, with common models including the Langmuir and Freundlich and pseudosecondorder kinetics. As identified by these studies, the main driving force for adsorption is electrostatic interactions between AO and the adsorbents. The review also encompasses competitive adsorption, adsorbent regeneration, alternative decontamination methods, and the pivotal role of computational research in optimizing adsorption processes. [ABSTRACT FROM AUTHOR]

Diketopyrrolopyrroles (DPPs) are a versatile group of dyes and pigments with valuable optoelectronic properties. In this work we report the synthesis of highly fluorescent DPP derivatives through straightforward nucleophilic aromatic substitution reactions with thiols and phenols. These nucleophilic substitutions occur at room temperature and manifest a remarkable selectivity for the 4-position of the pentafluorophenyl groups. Both symmetrical (disubstitution) and non-symmetrical (monosubstitution) DPP derivatives are formed in excellent overall yields. The optical properties of the newly synthesized compounds are also discussed. The new platform may be useful for bioorthogonal chemistry.

The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois) (Hemiptera: Miridae), is a highly polyphagous insect feeding on many wild host plants and a pest of economically important cultivated crops. The landscape composition plays an important role on the population dynamics of tarnished plant bugs and merits further examination to better manage populations across the agroecosystem. In this study, we evaluated the potential of eight oral biomarkers in combination with an inexpensive and portable fluorescent adapter in order to track the movement of L. lineolaris. Tarnished plant bugs from a laboratory colony were exposed to 8 biomarkers (Safranin O, Acridine Orange, Rhodamine B., Fluorescein sodium salt, Acid Fuchsin, Brilliant Blue, Fluorescent Brightener 28, and Carmoisine) contained in a 10% honey solution using three ingestion methods (dye-infused floral foam, dye-overlaid diet, and a dye-incorporated diet). At 24, 48, and 72 h post-exposure, the L. lineolaris nymphs and adults were removed from each treatment, killed by freezing and evaluated for florescence using a microscope equipped with a NightSea™ Florescence adapter under different lighting and filter combinations. The results indicated that Safranin O, Rhodamine B, and Acridine Orange are potentially useful as oral biomarkers for both nymph and adult L. Lineolaris when incorporated into a honey water solution and delivered via ingestion by floral foam, diet-overlay, or incorporated into their diet. This study provides information usable by ecologists and entomologists for to selecting biomarkers for particular life stages to address the different mobile phases of an insect life cycle. Resumen La chinche lygus, Lygus lineolaris (Palisot de Beauvois) (Hemiptera: Meridae) es un insecto altamente polífago que se alimenta de hospederos naturales y cultivos de importancia económica. El medio ambiente juega un papel importante sobre las dinámicas poblacionales de la chinche lygus, y amerita estudios más a fondo para un mejor manejo de sus poblaciones a través del ecosistema. En el presente estudio se evaluó el potencial de ocho marcadores biológicos-orales en combinación con un adaptador fluorescente portátil y fácil de adquirir con el fin de hacer el seguimiento en los movimientos de L. lineolaris. Una colonia de laboratorio de chinche lygus se expuso a 8 biomarcadores (Safranin O, Acridine naranja, Rhodamine B., Flourescein sodio sal, ácido Fuchsin, Brilliant azul, Brillante Floreciente 28, tintura Carmoisine) en una solución de agua con miel al 10%, los cuales se utilizaron tres métodos de ingestión; infusión de tintura en espuma florar, tintura superpuesta sobre la superficie de dieta y tintura incorporada en dieta. En intervalos de 24, 48 y 72 postratamiento, ninfas y adultos de L. lineolaris se removieron de cada tratamiento y se trasladaron a un congelador hasta que murieron. Los cadáveres fueron evaluados por florescencia usando un microscopio equipado con un adaptador NighSea TM fluorescente bajo diferentes combinaciones de luces y filtros. Los resultados indicaron que Safranin O, Rhrodamine B y Acridine naranja, son potencialmente útiles como marcadores biológico-orales para ninfas y adultos de L. lineolaris cuando se incorporan en agua-miel humedecida en espuma floral, solución puesta en la superficie de dieta y solución incorporada en dieta. Este estudio proporciona información útil para ecólogos y entomólogos para seleccionar marcadores biológicos para determinados estados de vida enfocados en las fases móviles del ciclo de vida de un insecto. [ABSTRACT FROM AUTHOR]

Poly(methyl methacrylate) (PMMA) colloidal particles are nowadays extensively used in several applications and more specifically in nanotechnology. Challenges are focused on the green synthesis process leading to size‐controlled particles. In the present work, PMMA particles were successfully synthesized using tandem acoustic emulsification in water without organic solvent, and cross‐linkers. 2,2′‐azobis(2‐methylpropionamidine) dihydrochloride (AIBA) or ammonium persulfate (APS), were used as initiators. Parameters leading to size control were clearly identified. Consequently, the cooling rate of the solution after polymerization time appears dominating. Particle size distribution was monodispersed for both initiators. A nonionic surfactant, Tween 20, was also added, leading to a decrease in size particle and an increase in synthesis yield. Depending on the chemical groups provided by the initiator, PMMA particles appear negatively or positively charged. These charges located on the particle surface led to stable particle dispersion by limiting aggregation phenomena. Tunable surface charge was confirmed across the elaboration of coatings only made of PMMA particles, using conventional techniques wherein charged species are needed (Layer‐by‐Layer assembly and electrophoretic deposition). PMMA particles were also labelled using fluorescent dyes. Fluorescein and Nile Blue A were loaded during the polymerization process to ensure a homogeneous distribution of the dyes within the particles. [ABSTRACT FROM AUTHOR]

This study focuses on derivatizing 1‐(dicyanomethylene)indan as a viscosity sensor. The indan was extended with various functionalized naphthaldehydes under a push–pull design strategy. Among synthesized derivatives, salt‐capped derivatives exhibited an excellent linearity between fluorescent intensity and viscosity (R2 = 0.99), and further investigation underscores the reversible nature of fluorescence intensity changes at two temperatures as an important trait of viscosity sensors. [ABSTRACT FROM AUTHOR]

The xylem undergoes physiological changes in response to various environmental conditions during the process of plant growth. To understand these physiological changes, it is extremely important to observe the transport of xylem. In this study, the distribution and structure of vascular bundle in Lilium lancifolium were observed using the method of semithin section. Methods for introducing a fluorescent tracer into the xylem of the stems were evaluated. Then, the transport rule of 5(6)-Carboxyfluorescein diacetate (CFDA) in the xylem of the stem of L. lancifolium was studied by fluorescence dye in live cells tracer technology. The results showed that the vascular bundles of L. lancifolium were scattered in the basic tissue, the peripheral vascular bundles were smaller and densely distributed, and the closer to the center, the larger the volume of vascular bundles and the more sparsely distributed. The vascular bundles of L. lancifolium are limited external tenacity vascular bundles, which are composed of phloem and xylem. The most suitable method for CFDA labeling the xylem of isolated stem segments of L. lancifolium was solution soaking for 24 h. The running speed of CF in the isolated stem was 0.3 cm/h, which was consistent with the running speed of the material in the field. CF could be transported between the xylem and parenchyma cells, indicating that the material transport in the xylem could be through the symplastic pathway. The above results laid a foundation for the study of the xylem transport mechanism and the xylem pathogen disease of lily. [ABSTRACT FROM AUTHOR]

We prepared network polysaccharide nanoscopic hydrogels by crosslinking water-soluble chitosan (WSCS) with a carboxylate-terminated maltooligosaccharide crosslinker via condensation. In this study, the enzymatic elongation of amylose chains on chitosan-based network polysaccharides by glucan phosphorylase (GP) catalysis was performed to obtain assembly materials. Maltoheptaose (Glc7) primers for GP-catalyzed enzymatic polymerization were first introduced into WSCS by reductive amination. Crosslinking of the product with the above-mentioned crosslinker by condensation was then performed to produce Glc7-modified network polysaccharides. The GP-catalyzed enzymatic polymerization of the α-d-glucose 1-phosphate monomer from the Glc7 primers on the network polysaccharides was conducted, where the elongated amylose chains formed double helices. Enzymatic disintegration of the resulting network polysaccharide assembly successfully occurred by α-amylase-catalyzed hydrolysis of the double helical amyloses. The encapsulation and release of a fluorescent dye, Rhodamine B, using the CS-based network polysaccharides were also achieved by means of the above two enzymatic approaches. [ABSTRACT FROM AUTHOR]

Virus is a kind of simple microorganism specializing in intracellular parasitics, which is one of the main pathogens causing animal and plant diseases. The development of single-virus tracking（SVT）technology makes it possible to reveal the fine process of viral life activity. SVT is a new method to study the mechanism of viral infection based on fluorescence labeling and high spatio-temporal resolution imaging, which allows the observation of the life activity of a single or multiple viruses. In recent years, the SVT technology has made great progress in the study of virus entry, replication, and intercellular transmission, providing new insights into the mechanism of virus infection. In this paper, the principle and strategy types of virus labeling are briefly introduced, and the research progress of virus fluorescence labeling in single virus tracing is summarized, especially the labeling and imaging methods of different structures of viruses, aiming to provide new ideas for optimizing labeling strategies and solving the problem of efficient labeling of different types and structures of viruses. [ABSTRACT FROM AUTHOR]

Aims To assess the efficacy of two commercially available viability dyes, 5-cyano-2,3-di-(p-tolyl)tetrazolium chloride (CTC) and 5(6)-carboxyfluorescein diacetate (CFDA), in reporting on viable cell concentration and species using an all-fibre fluorometer. Methods and results Four bacterial species (two Gram-positive and two Gram-negative) commonly associated with food poisoning or food spoilage (Escherichia coli, Salmonella enterica, Staphylococcus aureus , and Bacillus cereus) were stained with CTC or CFDA and the fibre fluorometer was used to collect full fluorescence emission spectra. A good correlation between concentration and fluorescence intensity was found for Gram-negative bacteria between 107 and 108 colony-forming units (CFU) ml−1. There was no correlation with concentration for Gram-positive bacteria; however, the information in the CTC and CFDA spectra shows the potential to distinguish Gram-negative cells from Gram-positive cells, although it may simply reflect the overall bacterial metabolic activity under staining conditions from this study. Conclusions The limit of detection (LoD) is too high in the dip-probe approach for analysis; however, the development of an approach measuring the fluorescence of single cells may improve this limitation. The development of new bacteria-specific fluorogenic dyes may also address this limitation. The ability to differentiate bacteria using these dyes may add value to measurements made to enumerate bacteria using CTC and CFDA. [ABSTRACT FROM AUTHOR]

The realization of multifunctional advanced displays with better electro-optical properties is especially crucial at present. However, conventional integral full drive-based transparent display is increasingly failing to meet the demands of the day. Herein, partitioned polymerization as a novel preparation method was introduced innovatively into polymer-dispersed liquid crystals (PDLC) for realizing a step-driven display in agreement with fluorescent dye to solve the above drawback. At first, the utilization of fluorescent dye to endow the PDLC film with fluorescent properties resulted in a reduction in the saturation voltage of the PDLC from 39.7 V to 25.5 V and an increase in the contrast ratio from 58.4 to 96.6. Meanwhile, the experimental observations and theoretical considerations have elucidated that variation in microscopic pore size can significantly influence the electro-optical behavior of PDLC. Then, the step-driven PDLC film was fabricated through the exposure of different regions of the LC cell to different UV-light intensities, resulting in stepwise voltage–transmittance (V–T) responses of the PDLC film for the corresponding regions. Consequently, under appropriate driving voltages, the PDLC can realize three different states of total scattering, semi-transparent and total transparent, respectively. In addition, the PDLC film also embodied an outstanding anti-aging property and UV-shielding performance, which makes it fascinating for multifunctional advanced display applications. [ABSTRACT FROM AUTHOR]

Actinic keratoses (AKs) represent a common skin cancer in situ associated with chronic sun exposure. Early diagnosis and management of AKs are crucial to prevent their progression to invasive squamous cell carcinoma. Therefore, we investigated AK PRO score assessment using ex vivo confocal laser microscopy (EVCM) coupled with a novel fluorescent dye, FCF Fast Green, to explore its potential for the precise imaging and discrimination of collagen fibers. AK PRO assessment using EVCM demonstrated excellent conformity (95.8%) with histopathologic examination. The additional utilization of FCF Fast Green dye had no impact on AK visualization but showed a high affinity for collagen fibers enabling clear differentiation of collagen alterations between healthy and sun-damaged skin. The enhanced visualization of collagen fiber changes may aid clinicians in accurately identifying AKs and differentiating them from benign skin lesions. [ABSTRACT FROM AUTHOR]

The fast, affordable, and standardized detection of microplastics (MP) remains one of the biggest challenges in MP research. Comparable data are essential for appropriate risk assessments and the implementation of laws and limit values. The fluorescent staining of MP in environmental samples is a possible solution to this problem. This study investigates the optimization of a sample preparation process (hydrogen peroxide digestion) and the staining process (temperature, concentration, time, surfactants as staining aids) for using a specifically developed fluorescent dye for MP detection. The optimization is performed by comparing the sample preparation process and staining of MP from different polymers and natural particles. Further, the suitability of the optimized process for the detection of fluoropolymers and tire abrasion was tested. The results show that the optimized method (increased temperature and optimized stain concentration) can detect microplastics reliably with a total sample preparation and measurement time of 2.5–3 h per sample, reaching recovery rates of 93.3% (polypropylene) to 101.7% (polyester). Moreover, two of the three tested fluoropolymers could be detected reliably. Tire abrasion could not be detected with the here presented method, as the black color leads to strong quenching. A long-term study measuring the MP pollution in the effluent of a municipal wastewater treatment plant compared the optimized and original processes and confirmed the stability of the improved method for routine measurements and contamination control.

The fast, affordable, and standardized detection of microplastics (MP) remains one of the biggest challenges in MP research. Comparable data are essential for appropriate risk assessments and the implementation of laws and limit values. The fluorescent staining of MP in environmental samples is a possible solution to this problem. This study investigates the optimization of a sample preparation process (hydrogen peroxide digestion) and the staining process (temperature, concentration, time, surfactants as staining aids) for using a specifically developed fluorescent dye for MP detection. The optimization is performed by comparing the sample preparation process and staining of MP from different polymers and natural particles. Further, the suitability of the optimized process for the detection of fluoropolymers and tire abrasion was tested. The results show that the optimized method (increased temperature and optimized stain concentration) can detect microplastics reliably with a total sample preparation and measurement time of 2.5–3 h per sample, reaching recovery rates of 93.3% (polypropylene) to 101.7% (polyester). Moreover, two of the three tested fluoropolymers could be detected reliably. Tire abrasion could not be detected with the here presented method, as the black color leads to strong quenching. A long-term study measuring the MP pollution in the effluent of a municipal wastewater treatment plant compared the optimized and original processes and confirmed the stability of the improved method for routine measurements and contamination control. [ABSTRACT FROM AUTHOR]

Indocyanine green is a cyanine dye that displays fluorescent properties in the near-infrared region. Indocyanine green has good water solubility and can bind to plasma proteins in the body. After binding, it can display green fluorescence when irradiated by near-infrared fluorescence. Owing to its good imaging ability and low side effects, indocyanine green is widely used in the diagnosis and treatment of various tumors. Indocyanine green-assisted sentinel lymph node biopsy helps determine clean tumor boundaries, helps surgeons remove primary tumors completely, assists in microvascular anastomosis in head and neck repair and reconstruction, reduces operation time, evaluates blood perfusion to monitor flap status. In addition, indocyanine green has great potential in photodynamic therapy to specifically kill tumor cells. However, despite the benefits, studies regarding the application of indocyanine green in oral cancer are limited. Therefore, we conducted a literature review to explore the application of indocyanine green in oral cancer to benefit clinicians involved in the diagnosis and treatment of this disease. [ABSTRACT FROM AUTHOR]

Numerous agents such as near-infrared dyes that are characterized by specialized cancer imaging and cytotoxicity effects have key roles in cancer diagnosis and therapy via molecularly targeting special biological tissues, organelles and processes. In the present study, a novel fluorescent compound was demonstrated to inhibit cancer cell proliferation in a zebrafish model with slight in vivo toxicity. Further studies demonstrated selective staining of cancer cells and even putative cancer stem cells via accumulation of the dye in the mitochondria of cancer cells, compared with normal cells. Moreover, this compound was also used to image cancer cells in vivo using a zebrafish model. The compound displayed no apparent toxicity to the host animal. Overall, the data indicated that this compound was worthy of further evaluation due to its low toxicity and selective cancer cell imaging and killing effects. It could be a useful tool in cancer research. [ABSTRACT FROM AUTHOR]

Fluorescent dyes are commonly used as conservative groundwater tracers to track the migration of water. Over- or underestimation of important parameters such as the water flow rate can occur if the concentration of a dye is changed by unexpected reactions. Because such errors may seriously affect the results of experiments, the reactions and processes that change fluorescent dye concentrations need to be understood. In this study, we focused on the widely used fluorescent dye uranine (UR) and aimed to identify microbes contributing to decreases in UR concentrations in groundwater. First, we identified the conditions (water temperature, pH, and salinity) under which significant decreases in UR concentrations occurred to show that the decrease in UR concentrations were caused by the effects of microbes in the groundwater. Next, we obtained information about the metabolism of organic matter by potential contributing microbes. These results were used to narrow down possible microbes that could decrease the UR concentration. Analysis of the microbial community in groundwater using 16S rRNA gene sequencing was then used to further identify contributing microbes. Finally, a verification experiment was conducted using a strain of one of the identified microbes (Parapontixanthobacter aurantiacus). Our results showed that conservation of the concentration of fluorescent dye solutions prepared with on-site groundwater was affected by several microbes with different metabolic characteristics, including P. aurantiacus. When fluorescent dye solutions prepared with on-site groundwater are used in field investigations or tracer tests, the pros and cons of using fluorescent dyes should be carefully evaluated because of the potential effects of microbes in the groundwater.

Blue dyes are relatively uncommon in nature, and a novel dithiophene dye (RanB) is reported in this paper. This dye is derived from an old anti-osteoporotic drug and is a metal ion complexing agent, displaying a planar molecular structure, with two sets of carboxylate, isonitrile, thiophene, and iminodiacetate groups. The blue color originates from a strong absorption peak at 648 nm, accompanied by an unusual fluorescence at 555 nm, with higher energy compared to the main absorption band. RanB forms complexes with lanthanoid ions through the iminodiacetate groups and serves as an effective sensitizer for Tb3+ ions, heightening their emission and improving their use as luminescent agents. Its photo-physical properties and the interaction with Tb3+ have been investigated using absorption spectroscopy, steady-state and time-resolved fluorescence spectroscopy, along with computational methods (ZINDO/S and DFT). The RanB toxicity in human umbilical vein endothelial cells has also been tested, showing a lack of toxicity, holding promising prospects for application as a luminescent and coloring agent in pharmaceuticals and food.

We prepared network polysaccharide nanoscopic hydrogels by crosslinking water-soluble chitosan (WSCS) with a carboxylate-terminated maltooligosaccharide crosslinker via condensation. In this study, the enzymatic elongation of amylose chains on chitosan-based network polysaccharides by glucan phosphorylase (GP) catalysis was performed to obtain assembly materials. Maltoheptaose (Glc7) primers for GP-catalyzed enzymatic polymerization were first introduced into WSCS by reductive amination. Crosslinking of the product with the above-mentioned crosslinker by condensation was then performed to produce Glc7-modified network polysaccharides. The GP-catalyzed enzymatic polymerization of the α-d-glucose 1-phosphate monomer from the Glc7 primers on the network polysaccharides was conducted, where the elongated amylose chains formed double helices. Enzymatic disintegration of the resulting network polysaccharide assembly successfully occurred by α-amylase-catalyzed hydrolysis of the double helical amyloses. The encapsulation and release of a fluorescent dye, Rhodamine B, using the CS-based network polysaccharides were also achieved by means of the above two enzymatic approaches.

Blue dyes are relatively uncommon in nature, and a novel dithiophene dye (RanB) is reported in this paper. This dye is derived from an old anti-osteoporotic drug and is a metal ion complexing agent, displaying a planar molecular structure, with two sets of carboxylate, isonitrile, thiophene, and iminodiacetate groups. The blue color originates from a strong absorption peak at 648 nm, accompanied by an unusual fluorescence at 555 nm, with higher energy compared to the main absorption band. RanB forms complexes with lanthanoid ions through the iminodiacetate groups and serves as an effective sensitizer for Tb3+ ions, heightening their emission and improving their use as luminescent agents. Its photo-physical properties and the interaction with Tb3+ have been investigated using absorption spectroscopy, steady-state and time-resolved fluorescence spectroscopy, along with computational methods (ZINDO/S and DFT). The RanB toxicity in human umbilical vein endothelial cells has also been tested, showing a lack of toxicity, holding promising prospects for application as a luminescent and coloring agent in pharmaceuticals and food. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The discovery of fluorescence and the development of fluorescent dyes have enriched our lives and brought important applications. As a new member of the fluorescent dye family, aggregation-induced emission materials have developed rapidly in recent years. Herein, we introduce the development history of the aggregation-induced emission phenomenon, the application of the aggregation-induced emission (AIE) materials, and the prospect of the future. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Groundwater Hydrology is the property of Japanese Association of Groundwater Hydrology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Traditional chemotherapeutic drugs have limitations due to their non-targeted ability toward cancer cells. Stimuli-activatable prodrugs are designed to overcome these obstacles. However, the real-time monitoring of stimuli-activatable theranostic prodrugs still poses challenges. Herein, a prodrug (Fe–SS–HCy), consisting of a ferrocene-modified hemicyanine linked via a disulfide bond, is synthesized for anticancer imaging and therapy. Before activation, the toxicity of Fe–SS–HCy is low. The fluorescence of Fe–SS–HCy is quenched by ferrocene due to photoinduced electron transfer. After being taken up by cancer cells, the intracellular GSH activates Fe–SS–HCy, which releases HCy. The fluorescence of HCy is restored and selectively accumulates in the mitochondria, which further produce reactive oxygen species (ROS) to induce cancer cell death. Thus, this "off-on" fluorogenic HCy presents a new strategy for monitoring prodrug activation in real-time and for enhancing therapeutic efficacy with reduced side effects. [ABSTRACT FROM AUTHOR]

The realization of multifunctional advanced displays with better electro-optical properties is especially crucial at present. However, conventional integral full drive-based transparent display is increasingly failing to meet the demands of the day. Herein, partitioned polymerization as a novel preparation method was introduced innovatively into polymer-dispersed liquid crystals (PDLC) for realizing a step-driven display in agreement with fluorescent dye to solve the above drawback. At first, the utilization of fluorescent dye to endow the PDLC film with fluorescent properties resulted in a reduction in the saturation voltage of the PDLC from 39.7 V to 25.5 V and an increase in the contrast ratio from 58.4 to 96.6. Meanwhile, the experimental observations and theoretical considerations have elucidated that variation in microscopic pore size can significantly influence the electro-optical behavior of PDLC. Then, the step-driven PDLC film was fabricated through the exposure of different regions of the LC cell to different UV-light intensities, resulting in stepwise voltage–transmittance (V–T) responses of the PDLC film for the corresponding regions. Consequently, under appropriate driving voltages, the PDLC can realize three different states of total scattering, semi-transparent and total transparent, respectively. In addition, the PDLC film also embodied an outstanding anti-aging property and UV-shielding performance, which makes it fascinating for multifunctional advanced display applications.

Cellular membranes play a key role in cell communication with the extracellular environment and neighboring cells. Any changes, including their composition, packing, physicochemical properties and formation of membrane protrusions may affect cells feature. Despite its great importance, tracking membrane changes in living cells is still a challenge. For investigation of processes related to tissue regeneration and cancer metastasis, such as the induction of epithelial-mesenchymal transition, increased cell motility, and blebbing, the possibility to conduct prolonged observation of membrane changes is beneficial, albeit difficult. A particular challenge is conducting this type of research under detachment conditions. In the current manuscript, a new dithienothiophene S,S-dioxide (DTTDO) derivative is presented as an effective dye for staining the membranes of living cells. The synthetic procedures, physicochemical properties, and biological activity of the new compound are presented herein. In addition to the labeling of the membranes in a monolayer culture, its usefulness for visualization of membranes under detachment conditions is also demonstrated. Obtained data have proven that a new DTTDO derivative may be used to stain membranes in various types of experimental procedures, from traditional 2D cell cultures to unanchored conditions. Moreover, due to the specific optical properties, the background signal is reduced and, thus, observation may be performed without washing. [ABSTRACT FROM AUTHOR]

We report the photophysical properties, self‐assembly and biological evaluation of an isothiazolanthrone‐based dye, 7‐amino‐6H‐anthra[9,1‐cd]isothiazol‐6‐one (AAT), which reveals anticancer properties and can be potentially used as dye for monitoring cell viability. The solvent‐dependent photophysical studies suggest that the emission of AAT is sensitive to environment polarity due to which interesting changes in the colored emission may be observed owing to the charge transfer (CT) processes. AAT also self‐assembles to tree‐like branched morphologies and produce, a greenish emission inside the cells when imaged after short interval (15 mins) of incubation while a red fluorescence could be noted after 24 h. Interestingly, AAT also produce differential emission inside mouse normal cells as compared to its cancer cell lines since it possess anticancer activity. The experimental observations were also validated theoretically via computational modeling. [ABSTRACT FROM AUTHOR]

In recent years, the [2.2]paracyclophane (PCP) ring has attracted extensive attention due to its features of providing not only chirality and electron-donating ability but also steric hindrance, which reduces intermolecular π–π stacking interactions and thereby improves the fluorescence properties of dyes. To date, some circularly polarized luminescence (CPL)-active small organic molecules based on the PCP skeleton have been reviewed; however, the application of the PCP ring in improving the photophysical properties of fluorescent dyes is still limited, and new molecular design strategies are still required. This review summarizes and promotes the application of PCP in fluorescent dye design, fluorescence detection, and CPL modulation. We expect that this review will provide readers with a comprehensive understanding of the PCP skeleton and lead to further improvement in fluorescent dye design. [ABSTRACT FROM AUTHOR]

Rare-earth element-free fluorescent materials are eco-friendlier than other traditional fluorescent precursors, such as quantum dots and phosphors. In this study, we explore a simple and facile solution-based technique to prepare fluorescent films, which are highly stable under ordinary room conditions and show hydrophobic behaviour. The proposed hybrid material was designed with hybrid composites that use polyvinyl butyral (PVB) as a host doped with organic dyes. The red and green fluorescent films exhibited quantum yields of 89% and 80%, respectively, and both are very uniform in thickness and water resistant. Additionally, PVB was further compared with another polymeric host, such as polyvinylpyrrolidone (PVP), to evaluate their binding ability and encapsulation behaviour. Next, the effect of PVB on the optical and chemical properties of the fluorescent materials was studied using UV spectroscopy and Fourier transform infrared spectroscopy. The analysis revealed that no new bond was formed between the host material and fluorescent precursor during the process, with intermolecular forces being present between different molecules. Moreover, the thickness of the fluorescent film and quantum yield relation were evaluated. Finally, the hydrophobic nature, strong binding ability, and optical enhancement by PVB provide a powerful tool for fabricating a highly efficient fluorescent film with enhanced stability in an external environment based on its promising encapsulation properties. These efficient fluorescent films have a bright potential in colour conversion for next-generation display applications. [ABSTRACT FROM AUTHOR]

Spectral conversion of light introduced as a new technique to manage incoming light photons into the culture medium of photosynthetic microorganisms which can increase biomass production. In this work, a much more accurate value of the effect of spectral conversion on the growth of Chlorella sp. was obtained. For this purpose, the light source and Rhodamine 6G solution, as a spectral converter, was placed in the center of the culture flask, which was covered with aluminum foil. The loss of photons was largely avoided due to the additional homogeneous distribution of light. Modification of white light using the solution has increased biomass productivity up to 300%. Also, for biomass productivity of 1 mg L−1 day−1, the energy consumption of the white light source was reduced up to 75%. Nitrate uptake has also increased up to 28%, and intracellular lipid content has decreased, as well. [ABSTRACT FROM AUTHOR]

Microfluidic preconcentration enables the collection or extraction of low-abundance analytes at specific locations. It has attracted considerable attention as an essential technology in bioengineering, particularly for detection and diagnosis. Herein, we investigated the key parameters in the preconcentration of fluorescent dyes based on electrophoresis in a microfluidic electromembrane system. Commercial ion-exchange membrane (IEM)-integrated polydimethylsiloxane microfluidic devices were fabricated, and Alexa Fluor 488 and Rhodamine 6G were used as fluorescent dyes for sample preconcentration. Through experimental studies, the effect of the channel concentration ratio (CCR, concentration ratio of the main and buffer channels) on the performance of the sample preconcentration was studied. The results show that the preconcentration of the target sample occurs more effectively for a high CCR or high salt concentration of the main channel when the CCR is constant. We also demonstrate a phenomenon that the salt concentration in the electrolyte solution increases as the preconcentration progresses. Our results provide consolidated conditions for electrophoresis-based sample preconcentration in electromembrane systems. [ABSTRACT FROM AUTHOR]

In-resin CLEM (Correlative Light and Electron Microscopy) of Epon-embedded cells involves correlating fluorescence microscopy with electron microscopy in the same Epon-embedded ultrathin section. This method offers the advantage of high positional accuracy compared to standard CLEM. However, it requires the expression of recombinant proteins. In order to detect the localization of endogenous target(s) and their localized ultrastructures of Epon-embedded samples using in-resin CLEM, we investigated whether immunological and affinity-labeling using fluorescent dyes applied to in-resin CLEM of Epon-embedded cells. The orange fluorescent (λem ∼550 nm) and far-red (λem ∼650 nm) fluorescent dyes examined maintained a sufficient level of fluorescent intensity after staining with osmium tetroxide and subsequent dehydration treatment with ethanol. Immunological in-resin CLEM of mitochondria and the Golgi apparatus was achieved using anti-TOM20, anti-GM130 antibodies, and fluorescent dyes. Two-color in-resin CLEM revealed that wheat germ agglutinin-puncta showed the ultrastructures of multivesicular body-like structures. Finally, taking the advantage of high positional accuracy, volume in-resin CLEM of mitochondria in the semi-thin section (2 μm thick) of Epon-embedded cells was performed by focused ion beam scanning electron microscopy. These results suggested that the application of immunological reaction and affinity-labeling with fluorescent dyes to in-resin CLEM of Epon-embedded cells is suitable for analyzing the localization of endogenous targets and their ultrastructures by scanning and transmission electron microscopy.

The structure of the title compound, C30H42N4O2, has orthorhombic (Pbca) symmetry. This compound comprises a 4-amino-1,8-naphthalimide core with a 2,2,6,6-tetramethyl-4-piperidinyl substituent bonded to each nitrogen atom. The structure displays N--H· · ·O hydrogen bonding. The structure exhibits disorder of the main molecule. [ABSTRACT FROM AUTHOR]

Here, we present a direct comparison of different dyes and assays for the determination of protein concentrations. We compared the classical Bradford assay with two modern assays based on the fluorogenic dyes QuDye and ProteOrange and showed that the Bradford reagent achieved excellent results in the determination of protein concentrations as compared with more modern rivals. We also showed that standard approaches for determining the limit of detection (LoD) and limit of quantification (LoQ) may not work correctly with the tested dyes. We proposed a new approach that extends the standard algorithm for LoD and LoQ determination. This approach works well with both classical colorimetric and fluorogenic dyes, as well as with nontrivial fluorescent probes. [ABSTRACT FROM AUTHOR]

Chloroplasts are organelles composed of sub‐organellar compartments—stroma, thylakoids, and starch granules—and are surrounded by outer and inner envelope membranes (OEM and IEM, respectively). The chloroplast OEM and IEM play key roles not only as a barrier separating the chloroplast components from the cytosol but also in the interchange of numerous metabolites and proteins between the chloroplast interior and the cytosol. Fluorescent protein markers for the chloroplast OEM have been widely used to visualize the outermost border of chloroplasts. However, the use of marker proteins requires an established cellular genetic transformation method, which limits the plant species in which marker proteins can be used. Moreover, the high accumulation of OEM marker proteins often elicits abnormal morphological phenotypes of the OEM. Because the OEM can currently only be visualized using exogenous marker proteins, the behaviors of the chloroplast and/or its OEM remain unknown in wild‐type cells of various plant species. Here, we visualized the OEM using live‐cell staining with the fluorescent dyes rhodamine B and Nile red in several plant species, including crops. We propose rhodamine B and Nile red as new tools for visualizing the chloroplast OEM in living plant cells that do not require genetic transformation. Significance Statement: We established a live‐cell imaging method to visualize the chloroplast outer envelope membrane by staining living cells with fluorescent dyes. This method does not require genetic transformation and allows the observation of the chloroplast outer envelope membrane in various plant species. [ABSTRACT FROM AUTHOR]

High reciprocal pollination specialization leading to pollinator isolation can prevent interspecific pollen transfer and competition for pollinators. Sharing pollinators may induce mating costs, but it may also increase pollination services and pollen dispersal and offer more resources to pollinators, which may be important in case of habitat fragmentation leading to pollination disruption. We estimated pollen dispersal and pollinator isolation or sharing between two reproductively isolated genetic lineages of Silene nutans (Caryophyllaceae), which are rare and occur in parapatry in southern Belgium, forming two edaphic ecotypes. As inter-ecotypic crosses may lead to pollen wastage and inviable progeny, pollinator isolation might have evolved between ecotypes. Silene nutans is mainly pollinated by nocturnal moths, including nursery pollinators, which pollinate and lay their eggs in flowers, and whose caterpillars feed on flowers and seeds. Pollinator assemblages of the two ecotypes are largely unknown and inter-ecotypic pollen flows have never been investigated. Fluorescent powdered dyes were used as pollen analogues to quantify intra- and inter-ecotypic pollen transfers and seeds were germinated to detect chlorotic seedlings resulting from inter-ecotypic pollination. Nocturnal pollinators were observed using infrared cameras on the field, and seed-eating caterpillars were collected and reared to identify nursery pollinator species. No pollinator isolation was found: we detected longdistance (up to 5 km) inter-ecotypic dye transfers and chlorotic seedlings, indicating inter-ecotypic fertilization events. The rare moth Hadena albimacula, a nursery pollinator specialized on S. nutans, was found on both ecotypes, as well as adults visiting flowers (cameras recordings) as seed-eatingspecificities between the two reproductively isolated genetic lineages of S. nutans, and pollinator sharing instead of pollinator isolation when plants occur in parapatry, suggest that conservation of the host plant is also essential for sustaining (rare) pollinator and seed predator communities. caterpillars. However, S. nutans populations harbor different abundance and diversity of seed predator communities, including other rare nursery pollinators, suggesting a need for distinct conservation strategies. Our findings demonstrate the efficiency of moths, especially of nursery pollinators, to disperse pollen over long distances in natural landscapes, so to ensure gene flow and population sustainability of the host plant. Seed-predator. specificities between the two reproductively isolated genetic lineages of S. nutans, and pollinator sharing instead of pollinator isolation when plants occur in parapatry, suggest that conservation of the host plant is also essential for sustaining (rare) pollinator and seed predator communities. [ABSTRACT FROM AUTHOR]

Technological advancement leads researchers to develop multifunctional materials. Considering such trends, this study aimed to conjugate dual functionality in a single material to satisfy aesthetic and functional necessities. We investigated the potentiality of polysorbate 20 to perform as an effective ultraviolet absorber to develop UV-protective fabric. Coumarin derivative (Benzoxazolyl type) disperse dyes are well-known as fluorescent colors. On the other hand, luminescence materials are conspicuous and viable for fashion trends. Deliberate utilization of this inherent property of the dye and incorporation of polysorbate fulfilled the need for dual functionality. In addition, the knitted fabric structure enhanced wearing comfort as well. The effect of polysorbate consolidated the PET fabric as an excellent UV absorber, exhibiting an ultraviolet protection factor (UPF) of 53.71 and a blocking percentage of more than 95% for both UVA and UVB. Surface morphology was studied by scanning electron microscope (SEM). Fourier transform infrared spectroscopy (FTIR) with attenuated mode was used to investigate chemical modification. Moreover, X-ray diffraction (XRD) investigated the crystallography of the surface. Reflectance spectrophotometric analysis unveiled the color strength (K/S) of the dyed polyester fabrics. Finally, light fastness assessment revealed that the developed samples could resist a certain amount of photo fading under a controlled testing environment with the increment of ratings towards betterment. [ABSTRACT FROM AUTHOR]

• Characterization of fluorescent dye binding sites on antibodies. • Structure function analysis by mass spectrometry. • To have an inert tracer, minimal labeling is highly effective but not enough. • An inert tracer for determination of residence time distribution in chromatography. Fluorescently labeled antibodies are widely used to visualize the adsorption process in protein chromatography using confocal laser scanning microscopy (CLSM), but also as a tracer for determination of residence time distribution (RTD) in continuous chromatography. It is assumed that the labeled protein is inert and representative of the unlabeled antibody, ignoring the fact that labeling with a fluorescent dye can change the characteristics of the original molecule. It became evident that the fluorescently labeled antibody has a higher affinity toward protein A resins such as MabSelect Sure. This can be due to slight differences in hydrophobicity and net charge, which are caused by the addition of the fluorescent dye. However, this difference is eliminated when using high salt concentrations in the adsorption studies. In this work, the site occupancy of two labeled antibodies, MAb1 (IgG1 subclass) and MAb2 (IgG2 subclass) conjugated with the fluorescent dye Alexa Fluor™ 488 was elucidated by intact mass spectrometry (MS) and peptide mapping LC-MS/MS, employing a sequential cleavage with Endoproteinase Lys-C and trypsin and in parallel with chymotrypsin alone. It was shown that the main binding site for the dye was a specific lysine in the heavy chains of the MAb1 and MAb2 molecules, in positions 188 and 189 respectively. Other lysine residues distributed throughout the protein sequence were labeled to a lot lesser extent. The labeled antibody had a slightly different affinity to MabSelect Sure although its primary binding site (to Protein A) was not affected by labeling, despite the secondary region responsible for binding to the protein A was partly labeled. Overall, the fluorescent-labeled antibodies are a good compromise as an inert tracer in residence time distribution and chromatography studies because they are much cheaper than isotope-labeled antibodies; However, the differences between the labeled and unlabeled antibodies should be considered. [ABSTRACT FROM AUTHOR]

We explored the application of fluorescent dye doped Cholesteric Liquid Crystal (CLC) shells for anti-counterfeiting measures. These shells exhibit unique optical properties and, when infused with a fluorescent dye, produce a distinct fluorescent color upon exposure to UV light. We developed a microfluidic device using glass capillaries to generate uniform CLC shells. The shells were analyzed using a Polarizing Optical Microscope (POM) to study their defect structures. For anti-counterfeiting, QR code was encoded with CLC shells that were photopolymerized under ultraviolet light for enhanced durability. In daylight, the code reflects red and blue colors, but under UV light, it reveals the fluorescent dye color. This QR code can only be decrypted with UV illumination in both red and blue CLC shells. The color changes are easily visible to the naked eye, making this technique suitable for immediate verification. By utilizing this straightforward technique, security and chromic-based applications can be implemented with significantly increased cost-effectiveness and efficiency, surpassing the results of traditional approaches. • We built a microfluidic system employing glass capillaries to create monodispersed CLC shells. • Doping CLC shells with fluorescent dye enhances their applicability in security. • Encrypted QR codes reflect red and blue in daytime and release fluorescent dye under UV radiation, providing a dual-mode verification technique. • QR codes can only be decrypted under UV light, adding security to anti-counterfeiting methods. • CLC-based techniques are simpler, cost-effective, and efficient compared to traditional methods. [ABSTRACT FROM AUTHOR]

Traditional chemotherapeutic drugs have limitations due to their non-targeted ability toward cancer cells. Stimuli-activatable prodrugs are designed to overcome these obstacles. However, the real-time monitoring of stimuli-activatable theranostic prodrugs still poses challenges. Herein, a prodrug (Fe–SS–HCy), consisting of a ferrocene-modified hemicyanine linked via a disulfide bond, is synthesized for anticancer imaging and therapy. Before activation, the toxicity of Fe–SS–HCy is low. The fluorescence of Fe–SS–HCy is quenched by ferrocene due to photoinduced electron transfer. After being taken up by cancer cells, the intracellular GSH activates Fe–SS–HCy, which releases HCy. The fluorescence of HCy is restored and selectively accumulates in the mitochondria, which further produce reactive oxygen species (ROS) to induce cancer cell death. Thus, this “off-on” fluorogenic HCy presents a new strategy for monitoring prodrug activation in real-time and for enhancing therapeutic efficacy with reduced side effects.

Athira Raveendran,1,* Suchithra Poilil Surendran,2,* Jinhui Ser,1 Khurshed Alam,1 Hoonsung Cho,1 Yong Yeon Jeong3 1Department of Materials Science & Engineering, Chonnam National University, Gwangju, 61186, Republic of Korea; 2Department of Biomedical Sciences, Chonnam National University Medical School, Hwasun, 58128, Republic of Korea; 3Department of Radiology, Chonnam National University Hwasun Hospital, Hwasun, 58128, Republic of Korea*These authors contributed equally to this workCorrespondence: Hoonsung ChoDepartment of Materials Science & Engineering, Chonnam National University, Gwangju, 61186, Republic of KoreaTel +82-62-530-1717Fax +82-62-530-1699Email cho.hoonsung@jnu.ac.krYong Yeon JeongDepartment of Radiology, Chonnam National University Hwasun Hospital, Hwasun, 58128, Republic of KoreaEmail yjeong@jnu.ac.krIntroduction: Paclitaxel (PTX) is a conventional chemotherapeutic drug that effectively treats various cancers. The cellular uptake and therapeutic potential of PTX are limited by its slow penetration and low solubility in water. The development of cancer chemotherapy methods is currently facing considerable challenges with respect to the delivery of the drugs, particularly in targeting the tumor site without exerting detrimental effects on the healthy surrounding cells. One possibility for improving the therapeutic potential is through the development of tumor-targeted delivery methods.Methods: We successfully synthesized paclitaxel-MHI-148 conjugates (PTX-MHI) by coupling PTX with the tumor-targeting heptamethine cyanine dye MHI-148. Synthesis and purification were characterized using the absorbance spectrum and the results of time-of-flight mass spectrometry. Cellular uptake and cytotoxicity studies were conducted in vitro and in vivo.Results: PTX-MHI accumulates in tumor cells but not in normal cells, as observed by in vitro near-infrared fluorescent (NIRF) imaging along with in vivo NIRF imaging and organ biodistribution studies. We observed that MHI-148-conjugated PTX shows greater efficiency in cancer cells than PTX alone, even in the absence of light treatment. PTX-MHI could also be used for specific drug delivery to intracellular compartments, such as the mitochondria and lysosomes of cancer cells, to improve the outcomes of tumor-targeting therapy.Conclusion: The results indicated that PTX-MHI-mediated cancer therapy exerts an excellent inhibitory effect on colon carcinoma (HT-29) cell growth with low toxicity in normal fibroblasts (NIH3T3).Keywords: cancer therapy, colon cancer, bioconjugation, fluorescent dye, paclitaxel

Abstract Chloroplasts are organelles composed of sub‐organellar compartments—stroma, thylakoids, and starch granules—and are surrounded by outer and inner envelope membranes (OEM and IEM, respectively). The chloroplast OEM and IEM play key roles not only as a barrier separating the chloroplast components from the cytosol but also in the interchange of numerous metabolites and proteins between the chloroplast interior and the cytosol. Fluorescent protein markers for the chloroplast OEM have been widely used to visualize the outermost border of chloroplasts. However, the use of marker proteins requires an established cellular genetic transformation method, which limits the plant species in which marker proteins can be used. Moreover, the high accumulation of OEM marker proteins often elicits abnormal morphological phenotypes of the OEM. Because the OEM can currently only be visualized using exogenous marker proteins, the behaviors of the chloroplast and/or its OEM remain unknown in wild‐type cells of various plant species. Here, we visualized the OEM using live‐cell staining with the fluorescent dyes rhodamine B and Nile red in several plant species, including crops. We propose rhodamine B and Nile red as new tools for visualizing the chloroplast OEM in living plant cells that do not require genetic transformation. Significance Statement We established a live‐cell imaging method to visualize the chloroplast outer envelope membrane by staining living cells with fluorescent dyes. This method does not require genetic transformation and allows the observation of the chloroplast outer envelope membrane in various plant species.

High reciprocal pollination specialization leading to pollinator isolation can prevent interspecific pollen transfer and competition for pollinators. Sharing pollinators may induce mating costs, but it may also increase pollination services and pollen dispersal and offer more resources to pollinators, which may be important in case of habitat fragmentation leading to pollination disruption. We estimated pollen dispersal and pollinator isolation or sharing between two reproductively isolated genetic lineages of Silene nutans (Caryophyllaceae), which are rare and occur in parapatry in southern Belgium, forming two edaphic ecotypes. As inter-ecotypic crosses may lead to pollen wastage and inviable progeny, pollinator isolation might have evolved between ecotypes. Silene nutans is mainly pollinated by nocturnal moths, including nursery pollinators, which pollinate and lay their eggs in flowers, and whose caterpillars feed on flowers and seeds. Pollinator assemblages of the two ecotypes are largely unknown and inter-ecotypic pollen flows have never been investigated. Fluorescent powdered dyes were used as pollen analogues to quantify intra- and inter-ecotypic pollen transfers and seeds were germinated to detect chlorotic seedlings resulting from inter-ecotypic pollination. Nocturnal pollinators were observed using infrared cameras on the field, and seed-eating caterpillars were collected and reared to identify nursery pollinator species. No pollinator isolation was found: we detected long-distance (up to 5 km) inter-ecotypic dye transfers and chlorotic seedlings, indicating inter-ecotypic fertilization events. The rare moth Hadena albimacula, a nursery pollinator specialized on S. nutans, was found on both ecotypes, as well as adults visiting flowers (cameras recordings) as seed-eating caterpillars. However, S. nutans populations harbor different abundance and diversity of seed predator communities, including other rare nursery pollinators, suggesting a need for distinct conservation strategies. Our findings demonstrate the efficiency of moths, especially of nursery pollinators, to disperse pollen over long distances in natural landscapes, so to ensure gene flow and population sustainability of the host plant. Seed-predator specificities between the two reproductively isolated genetic lineages of S. nutans, and pollinator sharing instead of pollinator isolation when plants occur in parapatry, suggest that conservation of the host plant is also essential for sustaining (rare) pollinator and seed predator communities.

The four-cyclic condensed aromatic ketone 7H-benz[de]anthracene-7-one and its derivatives belong to the class of important anthraquinoid dyes, including laser and luminescent dyes. Current work is devoted to the synthesis of 3-cyanobenzanthrone and its evaluation of being a useful precursor for obtaining new 3-substituted derivatives with heterocyclic moieties, a handful of which have been synthesized up to now. The photophysical properties of the prepared compounds are investigated. The synthesized derivatives have pronounced fluorescence and are fluorescent "turn-off" probes for acidic environment. Therefore, these compounds can be used for pH sensing and as dyes in materials science and for visualization of biological structures. [ABSTRACT FROM AUTHOR]

Quantitative measurement of the degree of hepatic ischemia-reperfusion injury (IRI) is crucial for developing therapeutic strategies for its treatment. We hypothesized that clearance of fluorescent dye through bile metabolism may reflect the degree of hepatic IRI. In this study, we investigated sodium fluorescein clearance kinetics in blood and bile for quantifying the degree of hepatic IRI. Warm ischemia times (WITs) of 0, 30, or 60 min followed by 1 h or 4 h of reperfusion, were applied to the median and lateral lobes of the liver in Sprague-Dawley rats. Subsequently, 2 mg/kg of sodium fluorescein was injected intravenously, and blood and bile samples were collected over 60 min to measure fluorescence intensities. The bile-to-plasma fluorescence ratios demonstrated an inverse correlation with WIT and were distinctly lower in the 60-min WIT group than in the control or 30- min WIT groups. Bile-to-plasma fluorescence ratios displayed superior discriminability for short versus long WITs when measured 1 h after reperfusion versus 4 h. We conclude that the bile-to-blood ratio of fluorescence after sodium fluorescein injection has the potential to enable the quantification of hepatic IRI severity. [ABSTRACT FROM AUTHOR]

Although plastics have benefited our lives in terms of cost and convenience, the disposal of end-of-life plastics poses environmental problems, such as microplastics (MPs). Although the separation (e.g., filtration) and staining of MPs with fluorescent dye/solvent are generally accepted steps to observe MPs in an environmental matrix, in this study, an in situ selective fluorescent illumination of the MPs in water was attempted with the aid of surfactant. Nonpolar fluorescent dye in combination with surfactant affords nanometer-sized dye particles in water, which adsorb on MPs and penetrate the polymer matrix for effective staining and stable fluorescent behaviors. The effects of different staining parameters, including different dyes, surfactants, staining temperatures, staining times, dye/surfactant ratios, dye/MP ratios, and MP concentrations in aqueous solutions were investigated to better understand staining conditions. More interestingly, non-adsorbed free dye molecules in the staining solution were almost completely fluorescence-quenched by introducing the quenching agent, aniline, while the fluorescence intensity of the stained MP was maintained. By staining MPs with a dye/surfactant combination and subsequently quenching with aniline, in situ selective fluorescent illumination of the MPs in water was successfully achieved, which may eliminate the tedious separation/filtration procedure of MPs to accomplish the quick detection or monitoring of MPs. [ABSTRACT FROM AUTHOR]

Cellular membranes play a key role in cell communication with the extracellular environment and neighboring cells. Any changes, including their composition, packing, physicochemical properties and formation of membrane protrusions may affect cells feature. Despite its great importance, tracking membrane changes in living cells is still a challenge. For investigation of processes related to tissue regeneration and cancer metastasis, such as the induction of epithelial-mesenchymal transition, increased cell motility, and blebbing, the possibility to conduct prolonged observation of membrane changes is beneficial, albeit difficult. A particular challenge is conducting this type of research under detachment conditions. In the current manuscript, a new dithienothiophene S,S-dioxide (DTTDO) derivative is presented as an effective dye for staining the membranes of living cells. The synthetic procedures, physicochemical properties, and biological activity of the new compound are presented herein. In addition to the labeling of the membranes in a monolayer culture, its usefulness for visualization of membranes under detachment conditions is also demonstrated. Obtained data have proven that a new DTTDO derivative may be used to stain membranes in various types of experimental procedures, from traditional 2D cell cultures to unanchored conditions. Moreover, due to the specific optical properties, the background signal is reduced and, thus, observation may be performed without washing.