cas 2321-07-5, Fluorescein | Articles data

Articles about 2321-07-5Total 64 be found

Article title
Article abstract
Author
Journal number and time
Download

DESIGN, SYNTHESIS, AND PHOTOPHYSICAL PROPERTIES OF A NOVEL NIR II DYE FOR BIOLOGICAL IMAGING AND OPTOELECTRONIC DEVICES
In one aspect, the disclosure relates to fluorescent dyes that absorb and emit in the near infrared II (NIR II) range of the electromagnetic spectrum, methods of making same, compositions comprising same and methods of using the compositions to perform imaging on biological samples, and optoelectronic devices using the dyes. The dyes are small organic molecules that are inexpensive and facile to produce, can be water-soluble, have tunable properties, and are biocompatible and/or possess low toxicity.
-
(2022/03/04)

Synthesis and evaluation of intrinsic bioactivity of fluorescein and phenolphthalein derivatives
Fluorescein and phenolphthalein derivatives have been synthesized and screened for their bioactivity via molecular docking, cytotoxicity and antioxidant studies. In molecular docking studies, the compounds 3d have exhibited better glide score and hydrogen bonding ability when docked with t-RNA Dimethylallyltransferase. Antioxidant capabilities were evaluated via DPPH and ABTS radical scavenging activity. In this screening, compound 3d exhibited better inhibition efficiency in the DPPH and ABTS methods. Cytotoxicity of the compounds was assessed by the cell sustainability assay against human cervical cancer cell line (HeLa). All the synthesized compounds exhibited cytotoxic effects against HeLa cells and compounds 3d displayed better activity (IC50) than the standard drug (doxorubicin).
Bharathkumar, Kuruba,Durairaj, Arulappan,Mohanapriya, Raman,Obadiah, Asir,Ramanathan, Subramanian,Santhoshkumar, Palanichamy,Vasanthkumar, Samuel
(2021/09/28)

Lipase mimetic cyclodextrins
Glycerophospholipids (GPLs) perform numerous essential functions in biology, including forming key structural components of cellular membranes and acting as secondary messengers in signaling pathways. Developing biomimetic molecular devices that can detect specific GPLs would enable modulation of GPL-related processes. However, the compositional diversity of GPLs, combined with their hydrophobic nature, has made it challenging to develop synthetic scaffolds that can react with specific lipid species. By taking advantage of the host-guest chemistry of cyclodextrins, we have engineered a molecular device that can selectively hydrolyze GPLs under physiologically relevant conditions. A chemically modified α-cyclodextrin bearing amine functional groups was shown to hydrolyze lyso-GPLs, generating free fatty acids. Lyso-GPLs are preferentially hydrolyzed when part of a mixture of GPL lipid species, and reaction efficiency was dependent on lyso-GPL chemical structure. These findings lay the groundwork for the development of molecular devices capable of specifically manipulating lipid-related processes in living systems.
Lee, Youngjun,Devaraj, Neal K.
p. 1090 - 1094
(2021/02/06)

Chemistry of the carboxylic acid of dihydrofluorescein in oxidation and its application to fluorogenic ROS sensing
The conjugation site of dihydrofluorescein (H2F) is important for the rational design of H2F-based reactive oxygen species (ROS) sensors. Despite the prevalence of H2F analogs detecting cellular ROS, the role of the carboxylic acid of H2F in oxidation is still unclear. To get insight into the conjugation site of H2F, we synthesized H2F diacetate (2) and its amide derivative (3). The absorption and emission spectra of deacetylated 2 and 3 in the presence of H2O2/hematin showed that the carboxylic acid of H2F plays a crucial role in the oxidation of H2F. NMR and HPLC analysis of the oxidation product of deacetylated 3 showed a quantitative and fast generation of non-fluorescent spirolactam (F-Lactam). As regards these observations, we untouched the carboxylic acid at the 3rd position and designed an H2F-based ROS sensor (7) that conjugated the lipophilic chain at the 5th position instead. A series of confocal microscopic experiments of 7 demonstrated that 7 prefers the ER location and that ROS are elevated in the cells by ER stress inducers.
Le, Hoa Thi,Nguyen, Dinh Phi Long,Shin, Hyo Seob,Jung, Woong,Kang, Chulhun,Kim, Tae Woo
p. 461 - 468
(2021/07/19)

H2S donors with optical responses
Reactive sulfur species, including hydrogen sulfide (H2S), are important biological mediators and play key roles in different pathophysiological conditions. Small molecules that release H2S on demand, often referred to as “H2S donors,” constitute a key investigative tool for H2S-related research. A significant challenge, however, is correlating the rate of H2S release from such donors in complex systems with biological outcomes, because release rates are commonly perturbed by different biological environments. In this chapter, we outline an approach to use H2S donors that provide a fluorescent response upon H2S release to address this problem. These compounds leverage the intermediate release of carbonyl sulfide (COS), which is quickly converted to H2S by the endogenous enzyme carbonic anhydrase (CA), to provide activatable donors with an optical response. The described donors are activated by biological thiols and provide a fluorescence response that correlates directly with H2S delivery, which allows for delivered H2S levels to be measured in real time by fluorescence techniques.
Pluth, Michael D.,Zhao, Yu,Cerda, Matthew M.
p. 149 - 164
(2020/06/27)

Ti(IV) doping: An effective strategy to boost Lewis acidic performance of ZnO catalyst in fluorescein dye synthesis
Zn1-xTixO NPs were efficiently synthesized using a simple solution free mechanochemical method. The synthesized ZnO and Ti(IV)-doped ZnO catalysts are exhibited polycrystallinity, a hexagonal crystal structure, and roughly spherical agglomerates. The surface areas of the Zn1-xTixO catalysts were positively correlated with the doping percentage of Ti(IV), which also enhanced the Lewis acidity of the NPs. The catalysts exhibited excellent activity during the synthesis of fluorescein dyes. This methodology was also extended to sulfone-fluorescein dye synthesis.
Jadhav, Nirajkumar H.,Shinde, Dnyaneshwar R.,Sakate, Sachin S.,Rasal, Nishant K.,Pawar, Ramdas A.
p. 17 - 22
(2018/11/25)

COMPOUNDS FOR THIOL-TRIGGERED COS AND/OR H2S RELEASE AND METHODS OF MAKING AND USING THE SAME
Disclosed herein are embodiments of a compound that is capable of releasing COS and/or H2S upon reaction with a thiol-containing compound. The compound embodiments also can produce a detectable signal (e.g., a fluorescent signal) substantially concomitantly with COS and/or H2S release and/or can release an active agent, such as a therapeutic agent. Methods of making and using the compound embodiments also are disclosed.
-
Page/Page column 31

(2019/12/25)

Thermogravimetric and differential thermal analyses of fluorescein dye in inert and static air atmosphere
Fluorescein dye was prepared and characterized on the basis of microanalytical methods, FTIR, NMR and UV–visible spectroscopy in order to ensure its purity. Thermoanalytical study by TG, DTA and DTG was conducted in air as well as in inert atmosphere to determine the mode of decomposition and stability. The dye follows two-step and three-step decomposition pattern in air and nitrogen, respectively. The first stage of decomposition in both environments yields carbon monoxide and oxygen, whereas carbon monoxide and acetylene are the common products of second-stage decomposition except anthracene which is released only in air. The third step evolves ketene and acetylene under inert condition and the residue (observed at 1133?K) is a highly conjugated cyclic system. Char is the only residue which is identified at the end of decomposition under air after 893?K. The intermediates formed during the decomposition processes were also investigated. A possible mechanism of the thermal decomposition is proposed depending on pyrolysis, MS and IR spectral data.
Arshad, Muhammad,Masud, Khalid,Saeed, Aamer,Qureshi, Ammad Hussain,Shabir, Ghulam
p. 1385 - 1390
(2017/10/06)

Fluorescein as a Visible-Light-Induced Oxidase Mimic for Signal-Amplified Colorimetric Assay of Carboxylesterase by an Enzymatic Cascade Reaction
We have found that fluorescein possesses high visible-light-induced oxidase mimetic activity and could transform colorless 3,3′,5,5′-tetramethylbenzidine (TMB) into blue oxidized TMB (oxTMB) without unstable and destructive H2O2 under visible-light illumination. Instead, fluorescein uses oxygen as a mild and green electron acceptor, and its activity can be easily controlled by the switching “on/off” of visible light. In addition, the visible-light-induced catalytic mechanism was elucidated in detail and, as the main reactive species h+ and O2.? accounted for TMB oxidation. Based on the fact that fluorescein diacetate (FDA) possessed no activity and generated active fluorescein in situ in the presence of carboxylesterase (CaE), a signal-amplified sensing platform through a cascade reaction for CaE detection was constructed. Our proposed sensing system displayed excellent analytical performance for the detection of CaE in a wide linear range from 0.040 to 20 U L?1 with a low detection limit of 0.013 U L?1. This work not only changes the conventional concept that fluorescein is generally considered to be photocatalytically inert, but also provides a novel sensing strategy by tailoring the enzyme mimetic activity of fluorescein derivatives with analyte.
Liu, Li,Sun, Chaoqun,Yang, Juan,Shi, Ying,Long, Yijuan,Zheng, Huzhi
p. 6148 - 6154
(2018/04/06)

NbCl5-Promoted Synthesis of Fluorescein Dye Derivatives: Spectroscopic and Spectrometric Characterization and Their Application in Dye-Sensitized Solar Cells
Fluorescein has several applications owing to its properties, such as high molar absorptivity, high fluorescence quantum yield, high photostability, and wavelengths of absorption and emission in the visible region. The syntheses of fluorescein derivatives between phenol and anhydride derivatives by using NbCl5 as a Lewis acid is described. The products have high yields and short reaction times are observed. The study of the UV/Vis and fluorescence spectra of these derivatives and their application in dye-sensitized solar cells is also described.
da Silva, Bruno Henrique Sacoman Torquato,Bregadiolli, Bruna Andressa,Graeff, Carlos Frederico de Oliveira,da Silva-Filho, Luiz Carlos
p. 261 - 269
(2017/03/07)

Combinatorial Strategy to Identify Fluorescent Probes for Biothiol and Thiophenol Based on Diversified Pyrimidine Moieties and Their Biological Applications
We present a feasible paradigm of developing original fluorescent probes for target biomolecules via combinatorial chemistry. In this developmental program, pyrimidine moieties were investigated and optimized as unique recognition units for thiols for the first time through a parallel synthesis in combination with a rapid screening process. This time-efficient and cost-saving process effectively facilitated the developmental progress and provided detailed structure-reactivity relationships. As a result, Res-Biot and Flu-Pht were identified as optimal fluorescent probes for biothiol and thiophenol, respectively. Their favorable characteristics and superior applicability have been well demonstrated in both chemical and biological contexts. In particular, Res-Biot enables the direct visualization of biothiol fluctuations during oxidative stress and cell apoptosis, indicating its suitability in elucidation of a specific pathophysiological process in both living cells and living animals. Meanwhile, Flu-Pht is competent to visualize thiophenols without the interference from endogenous biothiols in living cells.
Xie, Xilei,Li, Mengmeng,Tang, Fuyan,Li, Yong,Zhang, Leilei,Jiao, Xiaoyun,Wang, Xu,Tang, Bo
p. 3015 - 3020
(2017/08/09)

Tetrazine-Responsive Self-immolative Linkers
Molecules that undergo activation or modulation following the addition of benign external small-molecule chemical stimuli have numerous applications. Here, we report the highly efficient “decaging” of a variety of moieties by activation of a “self-immolative” linker, by application of water-soluble and stable tetrazine, including the controlled delivery of doxorubicin in a cellular context.
Neumann, Kevin,Jain, Sarthak,Gambardella, Alessia,Walker, Sarah E.,Valero, Elsa,Lilienkampf, Annamaria,Bradley, Mark
p. 91 - 95
(2017/01/07)

Process for preparing fluorescein
The invention discloses a process for preparing fluorescein. The process comprises the following steps: taking critic acid as the catalyst, and reacting phthalic anhydride with resorcinol in the presence of a solvent to prepare fluorescein. The provided process for preparing fluorescein has the advantages of simple and convenient operation, low cost, high yield, safety, and high purity of finished product; the prepared fluorescein can meet the pharmaceutical requirements, and the process can be applied to industrial production.
-
Paragraph 0037; 0038; 0039; 0042; 0043; 0044

(2017/08/23)

Use of metal-accumulating plants for implementing chemical reactions
The use of metal-accumulating plants for implementing chemical reactions.
-
Page/Page column 41

(2015/10/28)

The Development of Fluorescent Probes for Visualizing Intracellular Hydrogen Polysulfides
Endogenous hydrogen polysulfides (H2Sn; n>1) have been recognized as important regulators in sulfur-related redox biology. H2Sn can activate tumor suppressors, ion channels, and transcription factors with higher potency than H2S. Although H2Sn are drawing increasing attention, their exact mechanisms of action are still poorly understood. A major hurdle in this field is the lack of reliable and convenient methods for H2Sn detection. Herein we report a H2Sn-mediated benzodithiolone formation under mild conditions. This method takes advantage of the unique dual reactivity of H2Sn as both a nucleophile and an electrophile. Based on this reaction, three fluorescent probes (PSP-1, PSP-2, and PSP-3) were synthesized and evaluated. Among the probes prepared, PSP-3 showed a desirable off/on fluorescence response to H2Sn and high specificity. The probe was successfully applied in visualizing intracellular H2Sn.
Chen, Wei,Rosser, Ethan W.,Matsunaga, Tetsuro,Pacheco, Armando,Akaike, Takaaki,Xian, Ming
supporting information
p. 13961 - 13965
(2016/01/25)

Rapid and selective detection of Cys in living neuronal cells utilizing a novel fluorescein with chloropropionate-ester functionalities
A chloropropionate-caged fluorescein probe allows for prompt detection of cysteine over other biothiols, e.g., homocysteine with a limit of detection of 12.8 μM.
Murale, Dhiraj P.,Kim, Hwajin,Choi, Wan Sung,Churchill, David G.
p. 5289 - 5292
(2014/01/23)

Single label comparative hybridization
The present invention provides methods of detecting and mapping chromosomal or genetic abnormalities associated with various diseases or with predisposition to various diseases, or to detecting the phenomena of large scale copy number variants. In particular, the present invention provides advanced methods of performing array-based comparative hybridization that allow reproducibility between samples and enhanced sensitivity by using the same detectable label for both test sample and reference sample nucleic acids. Invention methods are useful for the detection or diagnosis of particular disease conditions such as cancer, and detecting predisposition to cancer based on detection of chromosomal or genetic abnormalities and gene expression level. Invention methods are also useful for the detection or diagnosis of hereditary genetic disorders or predisposition thereto, especially in prenatal samples. Moreover, invention methods are also useful for the detection or diagnosis of de novo genetic aberrations associated with post-natal developmental abnormalities.
-
(2015/01/06)

Molecular-level understanding of the photocatalytic activity difference between anatase and rutile nanoparticles
The generation of oxidants on illuminated photocatalysts and their participation in subsequent reactions are the main basis of the widely investigated photocatalytic processes for environmental remediation and selective oxidation. Here, the generation and the subsequent diffusion of ·OH from the illuminated TiO2 surface to the solution bulk were directly observed using a single-molecule detection method and this molecular phenomenon could explain the different macroscopic behavior of anatase and rutile in photocatalysis. The mobile ·OH is generated on anatase but not on rutile. Therefore, the photocatalytic oxidation on rutile is limited to adsorbed substrates whereas that on anatase is more facile and versatile owing to the presence of mobile ·OH. The ability of anatase to generate mobile COH is proposed as a previously unrecognized key factor that explains the common observations that anatase has higher activity than rutile for many photooxidative reactions.
Kim, Wooyul,Tachikawa, Takashi,Moon, Gun-Hee,Majima, Tetsuro,Choi, Wonyong
supporting information
p. 14036 - 14041
(2015/02/19)

Extremely selective fluorescence detection of cysteine or superoxide with aliphatic ester hydrolysis
A novel fluorescence probe modality demonstrated with fluorescein affords a highly selective aqueous-based detection of cysteine over other biothiols, e.g. homocysteine, with a limit of detection of 11.3 μM.
Murale, Dhiraj P.,Kim, Hwajin,Choi, Wan Sung,Kim, Youngsam,Churchill, David G.
p. 46513 - 46516
(2014/12/12)

Use of compositions obtained by calcing particular metal-accumulating plants for implementing catalytical reactions
The invention relates to the use of compositions derived from metal-accumulating plants, wherein the metals are more particularly zinc, nickel and copper, for implementing chemical reactions especially catalytical reactions, a method for the preparation of specific Ni-containing composition, and said Ni-containing composition.
-
Page/Page column

(2014/09/03)

A reaction based colorimetric as well as fluorescence 'turn on' probe for the rapid detection of hydrazine
A fluorescein based reactive probe has been designed and synthesized to detect hydrazine selectively over other common analytes. We used here 4-bromobutyrate as a masking unit of fluorescein dye. Hydrazine plays here the role of a de-masking agent to set free the fluorescein dye through a simultaneous substitution-cyclisation-elimination process. This leads to 'turn on' fluorescence with easily discernible color change with a fast response time (15 minutes). The Royal Society of Chemistry 2014.
Goswami, Shyamaprosad,Aich, Krishnendu,Das, Sangita,Basu Roy, Sohini,Pakhira, Bholanath,Sarkar, Sabyasachi
p. 14210 - 14214
(2014/04/17)

USE OF METAL-ACCUMULATING PLANTS FOR THE PREPARATION OF CATALYSTS THAT CAN BE USED IN CHEMICAL REACTIONS
The use of metal-accumulating plants for implementing chemical reactions.
-
(2013/02/27)

Nucleic acid size detection method
The present invention provides methods of determining the size of a particular nucleic acid segment of interest in a sample of nucleic acids through fragmentation of DNA, size fractionation, an optional second fragmentation, and identification using a marker sequence. In particular aspects, an expansion or reduction of tandem repeat sequences can be detected. In further aspects, carriers and individuals afflicted with fragile X syndrome or other diseases associated with tandem repeats can be distinguished from normal individuals.
-
(2012/05/04)

Inhibitory effects of cytochrome P450 enzymes CYP2C8, CYP2C9, CYP2C19 and CYP3A4 by Labisia pumila extracts
Ethnopharmacological relevance: Labisa pumila (LP), popularly known with its local name, Kacip Fatimah, is a well known herb grown in Indochina and Southeast Asia and is traditionally used to regain energy after giving birth in women. The propensity of LP to cause drug-herb interaction via cytochrome P450 (CYP) enzyme system has not been investigated. Aim of the study: To evaluate the in vitro inhibitory effects of various LP extracts (aqueous, ethanol, dichloromethane (DCM) and hexane) on cytochrome P450 2C8 (CYP2C8), CYP2C9, CYP2C19 and CYP3A4 activities. Materials and methods: Probe substrate-based high performance liquid chromatography (HPLC) methods were established for CYP2C9, CYP2C19 and CYP3A4 whereas a fluorescence-based enzyme assay was established for CYP2C8. The metabolite formations were examined after incubation of probe substrate with respective CYP isoform in the present or absent of LP extracts. The inhibitory effect of LP was characterized with kinetic parameters IC 50 and Ki values. Results: LP extracts showed differential effect of CYP activities with the order of inhibitory potency as follows: dichloromethane>hexane>ethanol>aqueous. This differential effect was only observed in CYP2C isoforms but not CYP3A4. Both the hexane and DCM extracts exhibited moderate to potent inhibition towards CYP2C activities in different modes including non-competitive, competive and mixed-type. The DCM effect was notably strong for CYP2C8 and CYP2C9 showing Ki values of below 1 μg/ml. The selectivity of LP for CYP2C isoforms rather than CYP3A4 may be attributed to the presence of relatively small, lipophilic yet slightly polar compounds within the LP extracts. Conclusions: The results of our study revealed that phytoconstituents contained in LP, particularly in hexane and dichloromethane extracts, were able to selectively inhibit CYP2C isoforms. The inactivation was characterized by low Ki values, in particular, in CYP2C8 and CYP2C9. These in vitro data indicate that LB preparations contain constituents that can potently inhibit CYP2C activities and suggest that this herb should be examined for potential pharmacokinetic drug interactions in vivo.
Pan, Yan,Tiong, Kai Hung,Mak, Joon Wah,Abd-Rashid, Badrul Amini,Ismail, Zakiah,Ismail, Rusli,Ong, Chin Eng
p. 586 - 591,6
(2020/07/30)

Exhaustive syntheses of naphthofluoresceins and their functions
Naphthofluorescein and/or seminaphthofluorescein derivatives possessing the additional benzene units to one or both sides of fluorescein were exhaustively constructed through Friedel-Crafts type reactions between corresponding aroylbenzoic acids and dihydroxynaphthalenes. Compound 4 works as a one-dye pH indicator, which shows red in strong acid condition and blue in basic solution. Compound 23 (diacetate of compound 4) shows good transitivity to the HEK 293 cells and acts as a fluorescent pigment for the living cell imaging. Compounds 5, 6, and 9 show fluorescent emission in the NIR region (>700 nm) and imply the potentialities of NIR fluorescent probes.
Azuma, Eriko,Nakamura, Naoko,Kuramochi, Kouji,Sasamori, Takahiro,Tokitoh, Norihiro,Sagami, Ikuko,Tsubaki, Kazunori
experimental part
p. 3492 - 3500
(2012/05/20)

Nitric oxide turn-on fluorescent probe based on deamination of aromatic primary monoamines
The stable, water-soluble, and nonfluorescent FA-OMe can sense nitric oxide (NO) and form the intensely fluorescent product dA-FA-OMe via reductive deamination of the aromatic primary amine. The reaction is accompanied by a notable increase of the fluorescent quantum yield from 1.5 to 88.8%. The deamination mechanism of FA-OMe with NO was proposed in this study. The turn-on fluorescence signals were performed by suppression of photoinduced electron transfer (PeT), which was demonstrated by density functional theory (DFT) calculations of the components forming FA-OMe and dA-FA-OMe. Furthermore, FA-OMe showed water solubility and good stability at physiological pHs. Moreover, the selectivity study indicated that FA-OMe had high specificity for NO over other reactive oxygen/nitrogen species. In an endogenously generated NO detection study, increasing the incubation time of FA-OMe with lipopolysaccharide (LPS) pretreated Raw 264.7 murine macrophages could cause an enhanced fluorescence intensity image. In addition, a diffusion/localization cell imaging study showed that FA-OMe could be trapped in Raw 264.7 cells. These cell imaging results demonstrated that FA-OMe could be used as a turn-on fluorescent sensor for the detection of endogenously generated NO.
Shiue, Tsun-Wei,Chen, Yen-Hao,Wu, Chi-Ming,Singh, Gyan,Chen, Hsing-Yin,Hung, Chen-Hsiung,Liaw, Wen-Feng,Wang, Yun-Ming
experimental part
p. 5400 - 5408
(2012/06/16)

Ferric hydrogensulphate as a recyclable catalyst for the synthesis of fluorescein derivatives
Polycondensation reactions of phenols with phthalic anhydride were carried out in the presence of ferric hydrogensulphate under melt conditions. The reactions proceeded in short reaction times by using a catalytic amount of Fe(HSO4)3 and the corresponding fluorescein derivatives were obtained in high yields. The simplicity, scale-up, along with the use of an inexpensive, non-toxic, recyclable catalyst of an environmentally benign nature, are other remarkable features of the procedure. The absorption and emission properties of these fluorescein derivatives were studied.
Eshghi, Hossein,Mirzaie, Narges
experimental part
p. 504 - 509
(2012/07/13)

Assay for mycobacterium avium/intracellulare nucleic acid
Disclosed is a method for determining the presence of Mycobacterium avium complex nucleic acids in a biological sample. In particular, the mig gene of M. avium and the DT1 gene of M. intracellulare are detected, preferably following amplification. In addition, the method distinguishes between species of M. avium and M. intracellulare. Also described are oligonucleotides that can be used as primers to amplify target genes such as mig and DT1 genes and as probes as well as kits containing the oligonucleotides.
-
(2010/12/26)

Selective perborate signaling by deprotection of fluorescein and resorufin acetates
(Figure Presented) The acetate derivatives of fluorescein and resorufln exhibited a prominent turn-on type signaling behavior toward BO3 - ions over other common anions. Signaling Is based on the selective deprotection of acetate groups by perborate, which resulted in significant chromogenic and fluorogenic signaling. Compound 1 also exhibited a pronounced perborate selectivity over other commonly used oxidants In 90% aqueous acetonitrile solution.
Choi, Myung Gil,Cha, Sunyoung,Park, Ji Eun,Lee, Haekyung,Jeon, Hye Lim,Chang, Suk-Kyu
supporting information; experimental part
p. 1468 - 1471
(2010/07/04)

Use of selenium to detect mercury in water and cells: An enhancement of the sensitivity and specificity of a seleno fluorescent probe
Inspired by the antitoxic function of selenium towards heavymetal ions, we designed an organoselenium fluorescent probe (FSe-1) for mercury. The reaction of FSe-1 and Hg2+ is an irreversible deselenation mechanism based on the selenophilic char
Tang, Bo,Ding, Baiyu,Xu, Kehua,Tong, Lili
body text
p. 3147 - 3151
(2009/11/30)

FLUORESCENT ISOTOPE TAGS AND THEIR METHOD OF USE
The present invention provides novel reactive fluorescent compounds that incorporate stable isotopic (deuterium, 13-carbon, 15-nitrogen, 18-oxygen) substitutions. The invention includes the use of these compounds, in combination with non-isotopically substituted analogs, for the purification, identification and relative quantification of proteins, peptides, saccharides, metabolites, and other biologically important compounds by combining liquid chromatography (LC) and mass spectrometry (MS). Fluorescent labeling of target compounds in this manner provides orders-of-magnitude sensitivity enhancement over traditional stable isotope labels, and also affords the possibility of simultaneous multiplexed analysis due to the multiwavelength nature of different fluorophores.
-
(2009/01/24)

Substractive single label comparative hybridization
Provided are methods of determining differences between nucleic acids in a test sample and a reference sample. In certain embodiments the methods are used for detecting and mapping chromosomal or genetic abnormalities associated with various diseases or with predisposition to various diseases, or to detecting the phenomena of large scale copy number variants. In particular, provided are advanced methods of performing array-based comparative hybridization that allow reproducibility between samples and enhanced sensitivity by using the same detectable label for both test sample and reference sample nucleic acids. Invention methods are useful for the detection or diagnosis of particular disease conditions such as cancer, and detecting predisposition to cancer based on detection of chromosomal or genetic abnormalities and gene expression level. Invention methods are also useful for the detection or diagnosis of hereditary genetic disorders or predisposition thereto, especially in prenatal samples. Moreover, invention methods are also useful for the detection or diagnosis of de novo genetic aberrations associated with post-natal developmental abnormalities.
-
(2009/04/24)

Fluorophotometric determination of hydrogen peroxide and other reactive oxygen species with fluorescein hydrazide (FH) and its crystal structure
Methods for the fluorophotometric determination of hydrogen peroxide (H2O2) and other reactive oxygen species (ROS) were proposed by using the fluorescence reaction between H2O2 or other ROS and fluorescein hydrazide (FH). In the determination of H 2O2, the calibration curve exhibited linearity over the H2O2 concentration range of 2.1-460 ng ml-1 at an emission wavelength of 527 nm with an excitation of 460 nm and with the relative standard deviations (n=6) of 4.06%, 1.78%, and 2.21% for 3.1 ng ml -1, 30.8 ng ml-1, and for 308 ng ml-1 of H 2O2, respectively. The detection limit for H 2O2 was 0.7 ng ml-1 due to three blank determinations (p=3). The calibration curves for ROS-related compounds were also constructed under the optimum conditions. This method was successfully applied in the assay of H2O2 in human urine. In addition, we performed the characterization of FH, and interesting information was obtained with regard to the relationship between the chemical structure and fluorescence.
Nakahara, Ryosuke,Fujimoto, Tsuyoshi,Doi, Mitsunobu,Morita, Kanako,Yamaguchi, Takako,Fujita, Yoshikazu
experimental part
p. 977 - 981
(2009/08/07)

SUBSTANTIALLY PURE FLUORESCEIN
The present invention is directed to an improved process for producing substantially pure fluorescein, as well as to substantially pure fluorescein compositions prepared by the process. The invention is particularly directed to the provision of pharmaceutical compositions for use in angiography. The substantially pure fluorescein produced by the process of the present invention is low in color, low in sodium chloride content, and substantially free of pyridine.
-
Page/Page column 23; 24

(2008/12/06)

Design of a phosphinate-based fluorescent probe for superoxide detection in mouse peritoneal macrophages
3′,6′-Bis(diphenylphosphinyl)fluorescein (PF-1) was synthesized as a highly selective and sensitive fluorescent probe for imaging O 2.- in living cells. The design strategy for the probe was based on the nucleophilic mechanism of O2.- to mediate deprotection of this probe to give fluorescein. Upon reaction with O 2.-, the probe exhibits a strong fluorescence response and high selectivity for O2.- over other reactive oxygen species and some biological compounds. The phosphinate-based probe, as a new fluorescent reagent, is cell-permeable and can detect micro molar changes of O2.- concentrations by using confocal microscopy in living cells. The unique combination of good selectivity, high sensitivity, good water solubility, and rapid reactivity establishes the potential value of the probe for facilitating investigations of the generation, metabolism, and mechanisms of superoxide-mediated cellular homeostasis and injury.
Xu, Kehua,Liu, Xia,Tang, Bo,Yang, Guiwen,Yang, Yong,An, Liguo
p. 1411 - 1416
(2008/02/04)

High purity phthalein derivatives and method for preparing same
The invention concerns high purity phthalcin derivatives enabling their use for medical applications or in the field of biotechnology, as well as their preparation method whereby a phthatic anhydride derivative is condensed with a naphthol or phenol derivative in an organic acid ester and the crystals of the resulting condensate are converted by action of a strong acid or one of its precursors in anhydrous medium.
-
Page/Page column 5

(2008/06/13)

Enzymatic characterization of O-GlcNAcase isoforms using a fluorogenic GlcNAc substrate
A highly sensitive fluorogenic hexosaminidase substrate, fluorescein di(N-acetyl-β-d-glucosaminide) (FDGlcNAc), was prepared essentially as described previously [Chem. Pharm. Bull. 1993, 41, 314] with some modifications. The fluorescent analog is a substrate for a number of hexosaminidases but here we have focused on the cytoplasmic O-GlcNAcase isoforms. Kinetic analysis using purified O-GlcNAcase and its splice variant (v-O-GlcNAcase) expressed in Escherichia coli suggests that FDGlcNAc is a much more efficient substrate (Km = 84.9 μM) than the conventional substrate, para-nitrophenyl 2-acetamido-2-deoxy-β-d-glucopyranoside (pNP-β-GlcNAc, Km = 1.1 mM) and a previously developed fluorogenic substrate, 4-methylumbelliferyl 2-acetamido-2-deoxy-β-d-glucopyranoside [MUGlcNAc, Km = 0.43 mM; J. Biol. Chem. 2005, 280, 25313] for O-GlcNAcase. The variant O-GlcNAcase, a protein lacking the C-terminal third of the full-length O-GlcNAcase, exhibited a Km of 2.1 mM with respect to FDGlcNAc. This shorter isoform was not previously thought to exhibit O-GlcNAcase activity based on in vitro studies with pNP-β-GlcNAc. However, both O-GlcNAcase isoforms reduced O-GlcNAc protein levels extracted from HeLa and HT-29 cells in vitro, indicating that the splice variant is a bona fide O-GlcNAcase. Fluorescein di-N-acetyl-β-d-galactosaminide (FDGalNAc) is not cleaved by these enzymes, consistent with previous findings that the O-GlcNAcase has substrate specificity toward O-GlcNAc but not O-GalNAc. The enzymatic activity of the shorter isoform of O-GlcNAcase was first detected by using highly sensitive fluorogenic FDGlcNAc substrate. The finding that O-GlcNAcase exists as two distinct isoforms has a number of important implications for the role of O-GlcNAcase in hexosamine signaling.
Kim, Eun Ju,Kang, Dae Ook,Love, Dona C.,Hanover, John A.
p. 971 - 982
(2007/10/03)

Methods of treating diseases responsive to induction of Apoptosis and screening assays
The present invention pertains to a method of treating, preventing or ameliorating a disease responsive to induction of the caspase cascade in an animal, comprising administering to the animal a compound which binds specifically to one or more Apoptosis Inducing Proteins (AIPs). AIPs include Transferrin Receptor Related Apoptosis Inducing Proteins (TRRAIPs), Clathrin Heavy Chain Related Apoptosis Inducing Proteins (CHCRAIPs), IQ motif containing GTPase Activating Protein Related Apoptosis Inducing Proteins (IQGAPRAIPs), and Heat Shock Protein Related Apoptosis Inducing Proteins (HSPRAIPs). The present invention also relates to screening methods useful for drug discovery of apoptosis inducing compounds. In particular, the screening methodology relates to using AIPs as a target for the discovery of apoptosis activators useful as anticancer agents. The screening methods of the present invention can employ homogenous or heterogenous binding assays using purified or partially purified AIPs; or whole cell assays using cells with altered levels of one or more AIPs. The invention also contemplates use of gambogic acid or GA-related compounds which bind AIPs and can accordingly be used to raise antibodies useful for drug discovery. Alternatively, labeled GA is used for competitive binding assays for drug discovery. Such assays afford high throughput screening of chemical libraries for apoptosis activators.
-
(2008/06/13)

Activatable probes and methods for in vivo gene detection
Probes for detecting a target polynucleotide are provided. One aspect provides a molecular beacon probe set wherein the donor molecular beacon comprises a quantum dot and an acceptor molecular beacon comprises at least one reporter. The probes optionally comprise a protein transduction domain, targeting signal, or a combination thereof. Methods for detecting target polynucleotides using the disclosed probes are also provided.
-
(2008/06/13)

Oligonucleotides comprising a molecular switch
This invention relates to oligonucleotides comprising a molecular switch which may exist in an “open” or “closed” position. The molecular switch portion of the probe is particularly sensitive to the identity of sequences complementary to the molecular switch. Oligonucleotides containing a molecular switch are applicable to all kinds of hybridization processes. Due to the sensitivity of the switch domain of the oligonucleotide, probes containing a molecular switch are particularly useful in the identification of single point mismatches. More specifically, a portion, but not all, of the oligonucleotide becomes unbound from a mismatched target. The invention further relates to methods of using said oligonucleotides for research reagents, and clinical diagnostics. An exemplary oligonucleotide comprises a first hybridizable domain, a second bridging block domain, and a third binding domain.
-
(2008/06/13)

Small molecule inhibitors of HER2 expression
Peptide mimetic small molecule inhibitors of Sur-2 are provided having the general formula:
-
(2008/06/13)

Heterocyclic FRETdye cassettes for labeling biological molecules and their use in DNA sequencing
Exploitation of suitably functionalized heterocyclic molecules, in the design and synthesis of Fluorescence Resonance Energy Transfer (FRET) cassettes and their corresponding dideoxynucleotide terminators culminated into efficient reagents for DNA sequencing. Additionally, these FRET cassettes/terminators, of the present invention, derived from different classes of heterocyclic systems have high potential to be used for general labelling of biological molecules to generate highly sensitized signals. Their preparation, energy transfer efficiency, and use as labels, specifically, in DNA sequencing reactions is disclosed.
-
(2008/06/13)

Method for producing water-soluble saccharide conjugates and saccharide mimetics by diels-alder reaction
The present invention relates to a method by which saccharide compounds can be prepared in a very easy way. This method comprises the steps of: (a) attaching at least one saccharide to a cyclic or acyclic diene, (b) reacting the saccharide-containing diene obtained in step (a) or a commercially available saccharide-containing diene with a dienophile by Diels-Alder reaction.
-
(2008/06/13)

Ionization and Tautomerism of Hydroxyxanthenes and Some Other Dyes in Ethanol
Protolytic equilibria of hydroxyxanthene dyes, Fluorescein and Eosin, as well as of some related compounds, in ethanol were studied by spectrophotometry. Stepwise ionization and tautomeric equilibrium constants were determined.
Mchedlov-Petrosyan
p. 267 - 274
(2007/10/03)

Imaging marker transgenes
Transgenic animals and cells are provided that comprise an imaging marker transgene. The imaging marker is expressed on the cell surface, and is capable of binding at high affinity a radiolabeled hapten that provides a signal useful in emission computed tomography. A preferred imaging marker is an antibody fragment, e.g. a single chain variable region (scFv). Radiolabeled haptens of interest include metal chelates, and may also include radiolabled small molecules. The animals or cells are monitored in vivo by administering the radiolabeled hapten, and localizing expression through SPECT or PET acquisition and reconstruction.
-
(2008/06/13)

Dual resonance energy transfer nucleic acid probes
Dual nucleic acid probes with resonance energy transfer moieties are provided. In particular, fluorescent or luminescent resonance energy transfer moieties are provided on hairpin stem-loop molecular beacon probes that hybridize sufficiently near each other on a subject nucleic acid, e.g. mRNA, to generate an observable interaction. The invention also provides lanthanide chelate luminescent resonance energy transfer moieties on linear and stem-loop probes that hybridize sufficiently near each other on a subject nucleic acid to generate an observable interaction. The invention thereby provides detectable signals for rapid, specific and sensitive hybridization determination in vivo. The probes are used in methods of detection of nucleic acid target hybridization for the identification and quantification of tissue and cell-specific gene expression levels, including response to external stimuli, such as drug candidates, and genetic variations associated with disease, such as cancer.
-
(2008/06/13)

Non-fluorescent quencher compounds and biomolecular assays
Bis-diazo,triaryl and aryldiazo-N-arylphenazonium quencher moieties, substituted with electron-withdrawing and electron-donating substituents which induce polarity in the delocalized aryl/diazo ring systems, are useful as labels when attached to biomolecules such as polynucleotides, nucleosides, nucleotides, and polypeptides. The quencher moieties are non-fluorescent and accept energy from fluorescent reporter labels by any energy-transfer mechanism, such as FRET. Fluorescence quencher compositions are useful in preparing quencher labelled biomolecules for various molecular biology assays based on fluorescence detection.
-
(2008/06/13)

Solvent-free synthesis of sulfonephthaleins, sulfonefluoresceins and fluoresceins under microwave irradiation
An efficient solvent-free synthesis of sulfonephthaleins, sulfonefluoresceins and fluoresceins under microwave irradiation is reported.
Cihelnik, Simon,Stibor, Ivan,Lhotak, Pavel
p. 1779 - 1789
(2007/10/03)

PEPTIDE NUCLEIC ACID CONJUGATES
A novel class of peptide nucleic acids are described which include a conjugate attached thereto. The peptide nucleic acids generally comprise ligands such as naturally occurring DNA bases attached to a peptide backbone through a suitable linker.
-
(2008/06/13)

Dense star polymer conjugates as dyes
Starburst conjugates which are composed of at least one dendrimer in association with at least one unit of a carried agricultural, pharmaceutical, or other material have been prepared. These conjugates have particularly advantageous properties due to the unique characteristics of the dendrimer.
-
(2008/06/13)