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Author : Hok Yan Cheng
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (17 download)
Download or read book Near Infrared Fluorescence Probes written by Hok Yan Cheng and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book DESIGN AND DEVELOPMENT OF NEAR-INFRARED FLUORESCENT PROBES FOR SENSING PH, HYPOXIA AND PEROXYNITRITE written by and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract : pH and hypoxia levels are two important diagnostic biomarkers in biological systems and abnormal levels will cause many diseases. The metabolism and transportation of peroxynitrite in biological systems involve a series of important enzymes and proteins. Peroxynitrite generation represents a crucial pathogenic mechanism in conditions such as stroke, myocardial infarction, chronic heart failure, diabetes, circulatory shock, chronic inflammatory diseases, cancer, and neurodegenerative disorders. As a result, it is very important to detect and evaluate the levels of pH, hypoxia, and peroxynitrite in vivo to study the functionality of enzymes and provide practical applications for cancer diagnosis and therapy. Fluorescence detection and imaging offer a sensitive non-invasive method because it provides clear images of cellular three-dimensional structures, and can illustrate cellular multiple overlapping structures simultaneously, and enable image-guided surgery. However, it is challenging to design fluorescent probes with good fluorescence signals, low background noise, and multifunctional detection capability. In order to overcome these drawbacks, we have designed and synthesized a series of excellent fluorescent probes to detect pH, hypoxia, and peroxynitrite with good fluorescence signals, fast responses, low background noise, and multifunctional detection capabilities. The probes combine advantages of near-infrared imaging such as low fluorescence background interference, less photodamage to cells and tissues, and deep-tissue penetration with ratiometric imaging, this latter aspect reduces systematic errors with solely intensity-based fluorescent probes caused by fluctuations in the excitation light source, variations in probe concentrations, and different probe compartmental localizations. We have developed a new backbone for making near-infrared fluorescent probes. This new backbone has a reactive chlorine group for modifying the detectors. Based on this new backbone, we introduced a pH-responsive detector to prepare three pH-sensitive near-infrared fluorescent probes with high fluorescence quantum yields. We designed and synthesized a series of fluorescent probes on detecting hypoxia level. The nitro group was introduced directly in the conjugation system of the fluorophore, which make it fast response and ultra-sensitive. Additionally, by changing the electron-withdrawing abilities of the substitution group on 9-position of acridine moiety, the fluorescent probes show a significant different detection limit and sensitivity towards nitroreducatse. For third project, we developed a fluorescent probe responding to peroxynitrite. The probe contains a near-infrared fluorophore and a coumarin moiety and connected through a conjugated triple bond linker. The ester group of the coumarin moiety in the conjugation system can enhance the sensitivity of the ONOO- detection. For the fourth project, we developed multi-response fluorescent probe. This probe can detect pH and ONOO- with different fluorescent changes. Base pH condition can induce an on-off fluorescent change on the probe, and the ONOO- can generate a ratiometric fluorescent change.
Author : S. Daehne
Publisher : Springer Science & Business Media
ISBN 13 : 9401151024
Total Pages : 452 pages
Book Rating : 4.4/5 (11 download)
Download or read book Near-Infrared Dyes for High Technology Applications written by S. Daehne and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book summarizes the results of the NATO Advanced Research Workshop on "Syntheses, Optical Properties, and Applications of Near-Infrared (NIR) Dyes in High Technology Fields" held at Trest (Czech Republic) from September 24 to 27, 1997. It was attended by 52 scientists from 16 countries, among them 18 participants from 8 Eastern-Europe. The Workshop has been stimulated by the great progress that has been made in utilizing NIR dyes in high technology areas. This has been triggered by the availability of reliable. vel)' small, and inexpensive laser diodes emitting in the NIR region which raise the analytical detection limits by several orders of magnitude, allow time-resolved measurements for temporal discrimination between spectrally similar species, and make possible miniaturization as well as remote sensing through space and by fiber optical techniques. Furthermore, NIR dyes proved to be vel)' important in other high technology fields such as laser physics, optical recording techniques, nonlinear optics, biochemistty and medicine.
Author : Stephen Summerfield
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (82 download)
Download or read book Near Infrared Fluorescence Spectroscopy written by Stephen Summerfield and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Fluorimetry in the very near infrared region ca. 600-1000nm is a new approach to photochemical analysis. The advantages include greatly reduced background fluorescence signals from important sample matrices (such as blood serum), reduced scattering, and reduced probability of sample decomposition. Also, the availability of low cost, efficient, stable and robust optical components (e.g. laser diodes and light emitting diodes), solid state detectors (e.g. single silicon photodiodes and diode arrays) and fibre optics, allows the construction of an inexpensive fluorimeter. In the near infrared region, there are some very bright fluorophores that can be adapted for use as fluorescent probes, labels for immunoassay, and as ion-pair agents. The advantageous performance of most types of fluorimetric analysis now undertaken In the ultraviolet and visible region of the spectrum may therefore be extended into the longer wavelength region. Excellent limits of detection are attainable, and some near infrared fluorophores show invaluable fluorescence probe properties, such as Nile Red. The most useful of the dye groups investigated were the phenoxazines and thiazines. Reactive derivatives of these dyes show great potential as fluorescent labels for Immunoassay. These dyes have also been used as probes due to their solvatochromism and sensitivity to pH.
Author :
Publisher :
ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (221 download)
Download or read book The Third Book of Reading Lessons written by and published by . This book was released on 1867 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Author : Jianwei Xu
Publisher : Elsevier
ISBN 13 : 0128243368
Total Pages : 698 pages
Book Rating : 4.1/5 (282 download)
Download or read book Aggregation-Induced Emission (AIE) written by Jianwei Xu and published by Elsevier. This book was released on 2022-04-17 with total page 698 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aggregation-Induced Emission (AIE): A Practical Guide introduces readers to the topic, guiding them through fundamental concepts and the latest advances in applications. The book covers concepts, principles and working mechanisms of AIE in AIE-active luminogens, with different classes of AIE luminogens reviewed, including polymers, three-dimensional frameworks (MOFs and COFs) and supramolecular gels. Special focus is given to the structure-property relationship, structural design strategies, targeted properties and application performance. The book provides readers with a deep understanding, not only on the fundamental principles of AIE, but more importantly, on how AIE luminogens and AIE properties can be incorporated in material development. Provides the fundamental principles, design and synthesis strategies of aggregation induced emission materials Reviews the most relevant applications in materials design for stimuli-responsive materials, biomedical applications, chemo-sensing and optoelectronics Emphasizes structural design and its connection to aggregation induced emission properties, also exploring the structure-property relationship
Author : Marcus Wilhelmsson
Publisher : John Wiley & Sons
ISBN 13 : 1118175867
Total Pages : 474 pages
Book Rating : 4.1/5 (181 download)
Download or read book Fluorescent Analogs of Biomolecular Building Blocks written by Marcus Wilhelmsson and published by John Wiley & Sons. This book was released on 2016-04-04 with total page 474 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fluorescent Analogs of Biomolecular Building Blocks focuses on the design of fluorescent probes for the four major families of macromolecular building blocks. Compiling the expertise of multiple authors, this book moves from introductory chapters to an exploration of the design, synthesis, and implementation of new fluorescent analogues of biomolecular building blocks, including examples of small-molecule fluorophores and sensors that are part of biomolecular assemblies.
Author : Yoshiaki Toyama
Publisher : Springer Nature
ISBN 13 : 9811379084
Total Pages : 292 pages
Book Rating : 4.8/5 (113 download)
Download or read book Make Life Visible written by Yoshiaki Toyama and published by Springer Nature. This book was released on 2019-10-02 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book describes marked advances in imaging technology that have enabled the visualization of phenomena in ways formerly believed to be completelyimpossible. These technologies have made major contributions to the elucidation of the pathology of diseases as well as to their diagnosis and therapy. The volume presents various studies from molecular imaging to clinical imaging. It also focuses on innovative, creative, advanced research that gives full play to imaging technology inthe broad sense, while exploring cross-disciplinary areas in which individual research fields interact and pursuing the development of new techniques where they fuse together. The book is separated into three parts, the first of which addresses the topic of visualizing and controlling molecules for life. Th e second part is devoted to imaging of disease mechanisms, while the final part comprises studies on the application of imaging technologies to diagnosis and therapy. Th e book contains the proceedings of the 12th Uehara International Symposium 2017, “Make Life Visible” sponsored by the Uehara Memorial Foundation and held from June 12 to 14, 2017. It is written by leading scientists in the field and is an open access publication under a CC BY 4.0 license.
Author : Sagarika Bhattacharya
Publisher : CRC Press
ISBN 13 : 1000334775
Total Pages : 117 pages
Book Rating : 4.0/5 (3 download)
Download or read book Nitric Oxide Sensing written by Sagarika Bhattacharya and published by CRC Press. This book was released on 2021-09-16 with total page 117 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although nitric oxide (NO) is an important biological signaling molecule, its free-radical electronic configuration makes it a most reactive molecule and the scariest colorless gas causing immense environmental and health hazards. Detection of NO levels in biological samples and in the atmosphere is therefore crucial. In the past few years, extensive efforts have been devoted to developing many active sensors and effective devices for detecting and quantifying atmospheric NO, NO generated in biological samples, and NO exhaled in the human breath. This book provides a concrete summary of recent state-of-the-art small-molecule probes and novel carbon nanomaterials used for chemical, photoluminescent, and electrochemical NO detection. One chapter is especially dedicated to the available devices used for detecting NO in the human breath that indirectly infers to lung inflammation. The authors with expertise in diverse dimensions have attempted to cover almost all areas of NO sensing.
Author : Fabio Doctorovich
Publisher : Elsevier
ISBN 13 : 0128011645
Total Pages : 425 pages
Book Rating : 4.1/5 (28 download)
Download or read book The Chemistry and Biology of Nitroxyl (HNO) written by Fabio Doctorovich and published by Elsevier. This book was released on 2016-09-01 with total page 425 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Chemistry and Biology of Nitroxyl (HNO) provides first-of-its-kind coverage of the intriguing biologically active molecule called nitroxyl, or azanone per IUPAC nomenclature, which has been traditionally elusive due to its intrinsically high reactivity. This useful resource provides the scientific basis to understand the chemistry, biology, and technical aspects needed to deal with HNO. Building on two decades of nitric oxide and nitroxyl research, the editors and authors have created an indispensable guide for investigators across a wide variety of areas of chemistry (inorganic, organic, organometallic, biochemistry, physical, and analytical); biology (molecular, cellular, physiological, and enzymology); pharmacy; and medicine. This book begins by exploring the unique molecule’s structure and reactivity, including important reactions with small molecules, thiols, porphyrins, and key proteins, before discussing chemical and biological sources of nitroxyl. Advanced chapters discuss methods for both trapping and detecting nitroxyl by spectroscopy, electrochemistry, and fluorescent inorganic cellular probing. Expanding on the compound’s foundational chemistry, this book then explores its molecular physiology to offer insight into its biological implications, pharmacological effects, and practical issues. Presents the first book on HNO (nitroxyl or azanone), an increasingly important molecule in biochemistry and pharmaceutical research Provides a valuable coverage of HNO’s chemical structure and significant reactions, including practical guidance on working with this highly reactive molecule Contains high quality content from recognized experts in both industry and academia
Download or read book DEVELOPMENT OF NEAR-INFRARED FLUORESCENT PROBES FOR MONITORING LYSOSOMAL PH CHANGES written by and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract : Lysosome is an acidic membrane-bound organelle containing more than 70 hydrolytic enzymes that breaks down different biological macromolecules. Substantial lysosomal pH disruption can cause lysosome malfunction and consequently lead to lysosomal storage disease. Therefore, it is essential to precisely monitor lysosomal pH changes in order to explore cellular functions and get insightful understanding of physiological and pathological processes. Fluorescence imaging based on fluorescent probes is a powerful technique to monitor lysosomal pH changes because of advantageous features including operational simplicity, high sensitivity, non-invasive approach, and high spatial resolution. However, most of the reported lysosomal pH probes are based on Stokes-shift fluorescence with lower energy emission under higher energy excitation, and exhibit less than 600 nm absorption and emission wavelengths, which causes cellular and tissue photodamage and contains biological fluorescence background. In order to avoid these issues, we developed near-infrared fluorescent probes based on single-photon anti-Stokes fluorescence with near-infrared excitations and emissions. We significantly improved biocompatibility and water-solubility of fluorescent probes by introducing mannose residues to the fluorophores through oligo(ethylene glycol) tethered spacers for sensitive detection of lysosomal pH changes in two near-infrared channels. In order to take advantage of ratiometric and near-infrared imaging to overcome systematic errors of intensity-based fluorescent probes caused by probe concentration variation and uneven distribution, temperature, solvent polarity, and excitation light fluctuation, we developed ratiometric near-infrared fluorescent probes for ratiometric detection of lysosomal pH changes by introducing tetraphenylethene (TPE) dyes to hemicyanine dyes. Gradual lysosomal pH decreases result in gradual increases of hemicyanine fluorescence, and corresponding concomitant decreases of TPE fluorescence. The probes allow for development of various ratiometric near-infrared fluorescent probes for quantitative and comparative reliable analyses of cations, reactive nitrogen, oxygen and sulfur species by conjugating various biosensing groups into the near-infrared hemicyanine moieties.
Download or read book NEAR-INFRARED FLUORESCENT PROBES FOR SENSITIVE DETERMINATION OF LYSOSOMAL & MITOCHONDRIAL PH IN LIVE CELLS written by and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract : Varied intracellular pH levels are critical for various physiological processes such as enzymatic activity, cell proliferation and apoptosis, ion transport, and muscle contraction. Cellular compartments, like lysosomes, must retain an acidic environment (pH ~ 4.5) to activate hydrolytic enzymes necessary for the breakdown of large biomolecules. Another cellular organelle, the mitochondria, provides the cell with energy and must retain an alkalis environment (pH ~ 8.0) for proper function. Substantial lysosomal and mitochondrial pH deviation is associated with cellular dysfunction and disease. Therefore, the precise detection of lysosomal and mitochondrial pH is essential to provide a better understanding of cellular physiological and pathological processes. Due to their superior features, such as cheap and simple operation, high spatial and temporal resolution, and noninvasive fluorescence imaging, fluorescent probes are the ideal methodology to visualize and monitor lysosomal and mitochondrial pH variation. We have developed three morpholine-functionalized BODIPY-based fluorescent probes that can be used to monitor lysosomal pH. The fluorescent probes are highly fluorescent under basic conditions, but when exposed to an acidic environment the fluorescence is quenched via an electron donor photoinduced energy transfer. Moreover, we have developed and synthesized a series of sterically hindered fluorescent probes based on spirolactam ring modifications. These modifications were developed by introducing 2-aminophenylboronic acid pinacol ester to rhodamine B, a near-infrared rhodamine dye, and a near-infrared hemicyanine dye. The probes display high fluorescence under acidic conditions but exhibit weak fluorescence under basic conditions due to the significant steric hindrance in the spirolactam ring. Since the probes were functional in an acidic environment, they were successfully applied for the sensing of lysosomal pH variations in living cells. We have also developed a NIR fluorescent probe to determine mitochondrial pH variations by incorporating an oxazolidine switch onto a near-infrared hemicyanine. The probe has the ability to rapidly switch from an oxazolidine moiety to a hemicyanine group when the pH level decreases from 10.0 to 5.0. This response to pH changes is reversible and has been successfully used to determine pH levels in mitochondria.
Author : Antonio Benayas
Publisher : Springer Nature
ISBN 13 : 3030320367
Total Pages : 391 pages
Book Rating : 4.0/5 (33 download)
Download or read book Near Infrared-Emitting Nanoparticles for Biomedical Applications written by Antonio Benayas and published by Springer Nature. This book was released on 2020-04-13 with total page 391 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book analyzes and evaluates the growing field of light-emitting nanoprobes as contrast agents for in vivo imaging and sensing. It is a comprehensive resource that critically analyzes the state of the art in an interdisciplinary manner, with a special focus on the shift of emission wavelengths into the near-infrared (NIR) spectral region (ranging from 0.7 to 2 microns), which has greatly contributed to the latest advances in biomedical imaging and sensing. This book discusses merits of different contrast agents at nanoscale, and how their unique chemical and structural properties lead to the emission and interaction of light within the NIR window. Both the NIR-emitting materials and various surface modification strategies governing their interactions with the biological system at the “nano” level are discussed. Furthermore, different experimental techniques and protocols for NIR-light-based in vivo imaging and sensing are addressed to shed light on further understanding of the advantages and limitations of each category of these nanoprobes. Assembles the state of the art heretofore appearing in scientific literature into a comprehensive, multi-perspective guidebook on near infrared-emitting nanomaterials in an assortment of biomedical applications; Explains the physical, chemical, and biological phenomena underlying near infrared-emitting nanomaterials for biomedical applications; Presents conceptual and experimental approaches surrounding a unique spectral range of light emission from nanosized contrast agents, while offering a clear explanation of basic and general phenomena regarding the interaction between light and biological tissues, such as absorption, scattering and autofluorescence.
Author : Kun Yin
Publisher : Springer
ISBN 13 : 9811364885
Total Pages : 94 pages
Book Rating : 4.8/5 (113 download)
Download or read book Design of Novel Biosensors for Optical Sensing and Their Applications in Environmental Analysis written by Kun Yin and published by Springer. This book was released on 2019-03-06 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces readers to the development of novel optical biosensors for environmental analysis. Environmental pollution has now become a serious problem, which threatens the health of human beings. Traditional analytical methods have a number of drawbacks, such as the need for professional operators and complicated instruments. After millions of years of evolution, biomolecules can perform various functions with good accuracy and efficiency due to their unique structures, offering a viable alternative to traditional methods. This work focuses on using new biological sensing strategies, e.g. those based on special biomaterials, bio-reactions or living cells, to establish novel biosensors. As these biosensors offer satisfactory optical response performance, they can be used to transform the recognition behavior of specific targets into optical signals and effectively detect target objects.
Author : G.C. Papageorgiou
Publisher : Springer Science & Business Media
ISBN 13 : 1402032188
Total Pages : 853 pages
Book Rating : 4.4/5 (2 download)
Download or read book Chlorophyll a Fluorescence written by G.C. Papageorgiou and published by Springer Science & Business Media. This book was released on 2007-11-12 with total page 853 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chlorophyll a Fluorescence: A Signature of Photosynthesis highlights chlorophyll (Chl) a fluorescence as a convenient, non-invasive, highly sensitive, rapid and quantitative probe of oxygenic photosynthesis. Thirty-one chapters, authored by 58 international experts, provide a solid foundation of the basic theory, as well as of the application of the rich information contained in the Chl a fluorescence signal as it relates to photosynthesis and plant productivity. Although the primary photochemical reactions of photosynthesis are highly efficient, a small fraction of absorbed photons escapes as Chl fluorescence, and this fraction varies with metabolic state, providing a basis for monitoring quantitatively various processes of photosynthesis. The book explains the mechanisms with which plants defend themselves against environmental stresses (excessive light, extreme temperatures, drought, hyper-osmolarity, heavy metals and UV). It also includes discussion on fluorescence imaging of leaves and cells and the remote sensing of Chl fluorescence from terrestrial, airborne, and satellite bases. The book is intended for use by graduate students, beginning researchers and advanced undergraduates in the areas of integrative plant biology, cellular and molecular biology, plant biology, biochemistry, biophysics, plant physiology, global ecology and agriculture.
Author : Huangxian Ju
Publisher : World Scientific
ISBN 13 : 9811237727
Total Pages : 997 pages
Book Rating : 4.8/5 (112 download)
Download or read book Biochemical Sensors (In 2 Volumes) written by Huangxian Ju and published by World Scientific. This book was released on 2021-06-08 with total page 997 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers the full scope of biochemical sensors and offers a survey of the principles, design and applications of the most popular types of biosensing devices. It is presented in 19 chapters, written by 20 distinguished scientists as well as their co-workers. The topics include the design of signal transducers, signal tags and signal amplification strategies, the structure of biosensing interfaces with new biorecognition elements such as aptamers and DNAzymes, and different newly emerging nanomaterials such as Au nanoclusters, carbon nitride, silicon, upconversion nanoparticles and two-dimensional materials, and the applications in wearable detections, biofuel cells, biomarker analyses, bioimaging, single cell analysis and in vivo sensing.By discussing recent advances, it is hoped this book will bridge the common gap between research literature and standard textbooks. Research into biochemical sensors and their biomedical applications is proceeding in a number of exciting directions, as reflected by the content. This book is published in honor of the 90th birthday of Professor Shaojun Dong, who performed many pioneering studies on modified electrodes and biochemical sensors.
Download or read book RATIOMETRIC NEAR-INFRARED FLUORESCENT PROBES FOR THE SENSITIVE DETECTION OF INTRACELLULAR PH AND BIO-THIOLS IN LIVE CELLS written by and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract : In the past twenty years, fluorescence sensing and imaging based on fluorescent probes has been developed as an imperative technique due to the merits including excellent sensitivity, operational simplicity, instant time effectiveness and outstanding selectivity in the research areas such as mineralogy, gemology, biological medicine, materials and environmental engineering. Protons act as a significant role in a variety of pathological and physiological processes, and there are obvious differences in the pH among organelles: the pH in lysosomes is acid within the range of 4.5-5.5, whereas mitochondrial pH is basic that can be as high as 8.0. Abnormal intracellular pH is always an indication of a disrupted pH homeostasis in the whole cell. Furthermore, intracellular bio-thiols are vital to cell metabolism, which by either elevated or deficiency levels of bio-thiols will lead to some diseases. Possessing the advantages of avoiding systematic errors and undesirable photophysical properties of certain fluorophores, novel near-infrared ratiometric fluorescent sensors for the accurately monitoring intracellular pH and biothiols have become the spotlight in research topics. Throughout this dissertation, we firstly have designed and synthesized two novel rhodamine-based dyes with high fluorescence quantum yield, good pH stability large Stokes shifts and excellent photostability by introducing an additional amino residue with fused rings into a classic rhodamine skeleton. We also have constructed a fluorescent sensor by incorporating a receptor to one of these dyes and applied it as an effective sensor for the quick and sensitive monitoring of lysosomal pH fluctuations. Then, we have prepared two sets of ratiometric fluorescent probes for the sensitive detection of lysosomal pH values. The former series were based on π-conjugation modulation strategy, which was accomplished by conjugating a visible coumarin motif to a classic near-infrared hemicyanine skeleton via a vinyl linker. The lysosome-targeting goal was reached by introducing a morpholine ligand or a o-phenylenediamine group to the hemicyanine acceptor. For the latter series, we have obtained three near-infrared ratiometric fluorescent sensors containing a TPE as a donor and a rhodamine as an acceptor for the quantitative, sensitive and comparative analysis of lysosomal pH alterations through FRET and TBET approaches. Furthermore, we have prepared two near-infrared hybrid rhodol dyes for the ratiometric and sensitive visualization of pH value alterations in mitochondria taking advantage of conjugating typical hemicyanine fluorophores into a classic rhodol motif. Upon pH changes, a rhodol hydroxyl group in the probe acts as a spiropyran switch, resulting in the change of π-conjugation and the appearance of a new fluorescent peak. Due to the positive charge, these two novel rhodol dyes possessed the mitochondria-targeting property. In the end, besides the ratiometric fluorescent pH probes, we have reported a FRET-based fluorescent sensor for the ratiometric, selective and accurate detection of cysteine (Cys), which was achieved by linking a visible coumarin skeleton and a near-infrared rhodamine motif through a piperazine spacer. This probe could be used to monitor the intracellular cysteine concentration ratiometrically and be further applied for imaging of Drosophila melanogaster larvae to detect cysteine concentration alterations in vivo.
