5-Aminofluorescein

5-Aminofluorescein (5-AF) is a new fluorescence marker, covalently bound to human serum albumin (AFL-HSA) [1] 5-aminofluorescein is a pH-sensitive biomaterial, is the targeted prodrug for synthesis of FA-FITC-Arg-PTX and FA-5AF- Glu-PTX..

References:
[1]. Ding R, et al. Pharmacokinetics of 5-aminofluorescein-albumin, a novel fluorescence marker of brain tumors during surgery. J Clin Pharmacol. 2011 May;51(5):672-8. [2]. Miao R, et al. Facile method for modification of the silicon nanowires and its application in fabrication of pH-sensitive chips. ACS Appl Mater Interfaces. 2013 Mar 13;5(5):1741-6. [3]. Wang T, et al. Fluorescein Derivatives as Bifunctional Molecules for the Simultaneous Inhibiting and Labeling of FTO Protein. J Am Chem Soc. 2015 Nov 4;137(43):13736-9. [4]. Shan L, et al. Multi-small molecule conjugations as new targeted delivery carriers for tumor therapy. Int J Nanomedicine. 2015 Sep 1;10:5571-91.

Specific detection of hypochlorite based on the size-selective effect of luminophore integrated MOF-801 synthesized by a one-pot strategy.[Pubmed:30720803]

Dalton Trans. 2019 Feb 19;48(8):2617-2625.

Hypochlorous acid (HClO), as one of the reactive oxygen species, plays a key role in a variety of physiological and pathological processes, while its accurate and specific in vitro monitoring remains a profound challenge. Herein, a novel luminescent metal-organic framework with high chemical stability has been designed for the specific detection of intracellular ClO-. The specificity was realized by the size-selective effect of MOF-801 with an ultra-small aperture, which can inhibit the entry of large-sized interferents into the cages of MOFs. A universal "ship in a bottle" approach has been proposed to construct this novel sensory platform, in which a large class of luminescent molecules containing carboxylic groups serve as modulators and combine with Zr6 clusters, eventually becoming the luminescent genes of these novel designed MOF-801. Luminescent molecules were readily locked in the framework since they were larger than the small pore entrance of MOF-801, skillfully solving the possible issue of dye leakage. By introducing active sites of 5-Aminofluorescein (AF) into MOF-801 (AF@MOF-801) as an example, an excellent ClO- sensing probe was fabricated, which showed strong reliability and excellent sensing performance toward intracellular ClO- with an ultrahigh linear correlation of the Stern-Volmer equation, a rapid response time as short as 30 s and a limit of detection (LOD) as low as 0.05172 muM. Compared with the free AF molecular probe, the specificity of AF@MOF-801 NPs toward ClO- was scarcely affected by other possibly coexistent large-sized interferents in biosystems. The in vitro monitoring of ClO- was also tested with these newly developed AF@MOF-801 NPs, prefiguring their great promise as a robust imaging tool to disclose the complexities of ClO- homeostasis and its pathophysiological contributions.

Ratiometric fluorescence sensor based on cholesterol oxidase-functionalized mesoporous silica nanoparticle@ZIF-8 core-shell nanocomposites for detection of cholesterol.[Pubmed:30029436]

Talanta. 2018 Oct 1;188:708-713.

A novel ratiometric fluorescence sensing system based on cholesterol oxidase-functionalized dual-color mesoporous silica nanoparticles (MSNs)@metal-organic framework core-shell nanocomposite is demonstrated for cholesterol detection. MSNs were first loaded with 5-Aminofluorescein (AF) inside pores and then wrapped with red-emission CdTe quantum dots (QDs) on the surface to seal in the dye molecules, forming the signal displaying unit (AF-MSN-QDs). Next, AF-MSN-QDs were encapsulated with zeolitic imidazolate framework (ZIF-8) to form a transition layer with distinct size-selectivity, which not only protected the cores from corrosion but also greatly decreased background interference from large molecules. More significantly, the ZIF-8 shells showed high affinity for most enzymes, which made it possible for cholesterol oxidase (ChOx) to self-organize on the surface of ZIF-8-encapsulated AF-MSN-QDs via chemo-physical adsorption, forming novel core-shell nanocomposites (AF-MSN-QD@ZIF-8-ChOx) as a sensing platform for cholesterol detection. The detectable signal was monitored by enzymatic product-quenching fluorescence of the QDs. The fluorescence changes of I520/I618 showed excellent linearity with H2O2 concentrations in the range of 5-100nM, with a limit of detection (LOD) as low as 0.89nM. As a proof-of-concept, cholesterol was selectively detected with beneficial LOD as low as 0.923mug/mL, demonstrating the great potential of this biosensor platform for other biologically important molecules with H2O2-producing oxidases.

Agents for fluorescence-guided glioma surgery: a systematic review of preclinical and clinical results.[Pubmed:27878374]

Acta Neurochir (Wien). 2017 Jan;159(1):151-167.

BACKGROUND: Fluorescence-guided surgery (FGS) is a technique used to enhance visualization of tumor margins in order to increase the extent of tumor resection in glioma surgery. In this paper, we systematically review all clinically tested fluorescent agents for application in FGS for glioma and all preclinically tested agents with the potential for FGS for glioma. METHODS: We searched the PubMed and Embase databases for all potentially relevant studies through March 2016. We assessed fluorescent agents by the following outcomes: rate of gross total resection (GTR), overall and progression-free survival, sensitivity and specificity in discriminating tumor and healthy brain tissue, tumor-to-normal ratio of fluorescent signal, and incidence of adverse events. RESULTS: The search strategy resulted in 2155 articles that were screened by titles and abstracts. After full-text screening, 105 articles fulfilled the inclusion criteria evaluating the following fluorescent agents: 5-aminolevulinic acid (5-ALA) (44 studies, including three randomized control trials), fluorescein (11), indocyanine green (five), hypericin (two), 5-Aminofluorescein-human serum albumin (one), endogenous fluorophores (nine) and fluorescent agents in a pre-clinical testing phase (30). Three meta-analyses were also identified. CONCLUSIONS: 5-ALA is the only fluorescent agent that has been tested in a randomized controlled trial and results in an improvement of GTR and progression-free survival in high-grade gliomas. Observational cohort studies and case series suggest similar outcomes for FGS using fluorescein. Molecular targeting agents (e.g., fluorophore/nanoparticle labeled with anti-EGFR antibodies) are still in the pre-clinical phase, but offer promising results and may be valuable future alternatives.

Fluorescein Derivatives as Bifunctional Molecules for the Simultaneous Inhibiting and Labeling of FTO Protein.[Pubmed:26457839]

J Am Chem Soc. 2015 Nov 4;137(43):13736-9.

The FTO protein is unequivocally reported to play a critical role in human obesity and in the regulation of cellular levels of m(6)A modification, which makes FTO a significant and worthy subject of study. Here, we identified that fluorescein derivatives can selectively inhibit FTO demethylation, and the mechanisms behind these activities were elucidated after we determined the X-ray crystal structures of FTO/fluorescein and FTO/5-Aminofluorescein. Furthermore, these inhibitors can also be applied to the direct labeling and enrichment of FTO protein combined with photoaffinity labeling assay.

Multi-small molecule conjugations as new targeted delivery carriers for tumor therapy.[Pubmed:26366078]

Int J Nanomedicine. 2015 Sep 1;10:5571-91.

In response to the challenges of cancer chemotherapeutics, including poor physicochemical properties, low tumor targeting ability, and harmful side effects, we developed a new tumor-targeted multi-small molecule drug delivery platform. Using paclitaxel (PTX) as a model therapeutic, we prepared two prodrugs, ie, folic acid-fluorescein-5(6)-isothiocyanate-arginine-paclitaxel (FA-FITC-Arg-PTX) and folic acid-5-Aminofluorescein-glutamic-paclitaxel (FA-5AF-Glu-PTX), composed of folic acid (FA, target), amino acids (Arg or Glu, linker), and fluorescent dye (fluorescein in vitro or near-infrared fluorescent dye in vivo) in order to better understand the mechanism of PTX prodrug targeting. In vitro and acute toxicity studies demonstrated the low toxicity of the prodrug formulations compared with the free drug. In vitro and in vivo studies indicated that folate receptor-mediated uptake of PTX-conjugated multi-small molecule carriers induced high antitumor activity. Notably, compared with free PTX and with PTX-loaded macromolecular carriers from our previous study, this multi-small molecule-conjugated strategy improved the water solubility, loading rate, targeting ability, antitumor activity, and toxicity profile of PTX. These results support the use of multi-small molecules as tumor-targeting drug delivery systems.

Conjugation of amino-bioactive glasses with 5-aminofluorescein as probe molecule for the development of pH sensitive stimuli-responsive biomaterials.[Pubmed:24722810]

J Mater Sci Mater Med. 2014 Oct;25(10):2243-53.

Bioceramics, such as silica-based glasses, are widely used in bone and teeth restoration. Nowadays, the association between nanotechnology and pharmacology is one of the most promising research fields in cancer therapy. The advanced processing methods and new chemical strategies allow the incorporation of drugs within them or on their functionalized surfaces. Bioceramics can act as local drug delivery systems to treat bone and teeth diseases. The present paper reports data related to the development of a pH-stimuli responsive bioactive glass. The glass conjugation with 5-Aminofluorescein (5-AF), through a pH-sensitive organic spacer, allows to produce a pH-responsive bioactive biomaterial: when it is exposed to specific pH changes, it can favour the release of 5-AF directly at the target site. 5-AF has been chosen as a simple, low cost, non toxic model to simulate doxorubicin, an anticancer drug. As doxorubicin, 5-AF contains an amino group in its structure in order to form an amide bond with the carboxylic functionalities of the glass. Raman spectroscopy and thermal analysis confirm the glass conjugation of 5-AF by means of an amide bond; the amount of 5-AF loaded was very high ( approximately 65 and 44 wt%). The release tests at two different pH (4.2 and 7.4) show that the amount of released 5-AF is higher at acid pH with respect to physiological one. This preliminary datum evidenced that a pH-sensitive drug delivery system has been developed. The low amount of 5-AF released (<1 wt% of the total 5-AF) is due to the very low solubility of 5-AF in aqueous medium. This disadvantage, may be overcome in a dynamic environment (physiological conditions), where it is possible to obtain a drug release system ensuring an effective therapeutic dose for long times and, at the same time, avoiding the drug toxicity.

New formulation of functionalized bioactive glasses to be used as carriers for the development of pH-stimuli responsive biomaterials for bone diseases.[Pubmed:24701982]

Langmuir. 2014 Apr 29;30(16):4703-15.

The aim of the present contribution is to prepare a functionalized bioactive glass potentially useful as prosthetic material, but also able to release organic molecules in response to a change of the pH environment. By this approach it is possible to develop devices which can be used for a triggered drug release in response to specific stimuli; this is an attractive research field, in order to avoid either systemic and/or local toxic effects of drugs. In particular, in the present paper we report data related to the development of a new formulation of bioactive glasses, their functionalization with organic molecules to obtain a pH-sensitive bond, their physicochemical characterization and in vitro bioactivity in simulated biological fluids (SBF), and organic molecule delivery tests at different pH. The glass functionalization, by means of a covalent reaction, allows us to produce a model of pH-responsive bioactive biomaterial: when it is exposed to specific pH changes, it can favor the release of the organic molecules directly at the target site. Cysteamine and 5-Aminofluorescein are used as model molecules to simulate a drug. The materials, before and after the different functionalization steps and in vitro release tests at different pH, have been characterized by means of different experimental techniques such as X-ray powder diffraction (XRPD), Raman, FTIR and fluorescence spectroscopies, N2 adsorption, thermogravimetric (TGA) and elemental analysis.

Determination of ATP using a double-receptor sandwich method based on molecularly imprinted membrane and fluorescence-labeled uranyl-salophen complex.[Pubmed:23884476]

Anal Bioanal Chem. 2013 Sep;405(23):7545-51.

A double-receptor sandwich method for the fluorescence determination of adenosine triphosphate (ATP) is proposed in this paper. The solid phase receptor on the surface of glass slides is a molecularly imprinted membrane (MIM) containing an artificial nanocavity. It is constructed by a molecular imprinting technique using adenosine monophosphate (AMP) as a template molecule. The labeled receptor is a uranyl-salophen complex containing a fluorescent group or uranyl-salophen-fluorescein (USF). It is synthesized with salophen, 5-Aminofluorescein, and uranyl. In a procedure of determining ATP, ATP in sample solution is first adsorbed on the surface of the glass slide through the combination of the AMP group in ATP with the nanocavity in MIM. Then, the adsorbed ATP binds USF through the coordination reaction of the phosphate group in ATP with uranyl in USF to form a sandwich-type structure of MIM-ATP-USF. The amount of ATP is detected through the fluorescence determination of USF bound on the slide. Under optimal conditions, the linear range for the determination of ATP is 0.3 to 4.8 nmol/mL with a detection limit of 0.041 nmol/mL. The proposed method has been successfully employed for the determination of ATP in real samples with the recoveries of 98.5 to 102.5 %.

Facile method for modification of the silicon nanowires and its application in fabrication of pH-sensitive chips.[Pubmed:23421422]

ACS Appl Mater Interfaces. 2013 Mar 13;5(5):1741-6.

A novel, facile, and effective method for modification of SiNWs or SiNW arrays has been developed. In this method, reaction between reductive Si-H bonds on the surface of SiNWs and the aldehyde group containing in organic molecules has been used for immobilization of organic molecules onto the surface of SiNW arrays. The method is time saving and can be operated at room temperature without any other complex reaction requirement. Fluorescence images, XPS, fluorescence spectra, and IR spectra were used for characterization of the modification. Through this method, a SiNW array-based pH sensitive chip was realized by covalently immobilizing 5-Aminofluorescein molecules onto the surface of SiNW arrays with glutaraldehyde as linker molecules. Fluorescence intensity of the chip increased with increasing of pH value and a linear relationship between fluorescence intensity and pH values was acquired. In addition, the chip has been successfully used for real-time and in situ monitoring of extracellular pH changes for live HeLa cells and the result exhibited fine resolution of time and space.

Intracellular protein delivery by hollow mesoporous silica capsules with a large surface hole.[Pubmed:22293239]

Nanotechnology. 2012 Mar 2;23(8):085101.

We prepared cell membrane-permeable hollow mesoporous silica capsules (HMSCs) by a simple new method. CTAB micellar assembly in cholesterol emulsion gave rise to a novel capsular morphology of the HMSC particles. The HMSCs consisted of mesostructured silica walls with a large surface hole (25-50 nm) and the average particle dimension was 100-300 nm. They exhibited high surface areas of up to 719.3 m(2) g(-1) and a mesoporous range of pores of 2.4-2.7 nm. The surface-functionalized HMSCs could also be prepared by a similar co-condensation method using tetraethoxysilane with various organoalkoxysilane precursors in the presence of cholesterol. These organically modified HMSCs could be further modified on demand. For example, a carboxy-functionalized HMSC could be surface-functionalized by a green fluorescent 5-Aminofluorescein (AFL) through an amidation reaction to afford a fluorescent AFL-HMSC. The hollow capsular morphology of the HMSCs with a large surface hole enabled us to develop very efficient intracellular delivery systems for membrane-impermeable ions, molecules, and various functional proteins. Non-covalent sequestration and delivery of proteins as well as covalent linkage of fluorescent molecules on the silica surface are effective for this system. The highly negatively charged green fluorescent probe mag-fluo-4 could be intracellularly delivered into HeLa cells by HMSC without any difficulty. The HMSCs could also effectively transport large functional proteins such as antibodies into HeLa cells. The efficiency of protein delivery by HMSC seems to be 3-22-fold higher than that of mesoporous silica nanospheres (MSNs) based on confocal laser scanning microscopy (CLSM) analysis.

5-Aminofluorescein (5-AF) is a new fluorescence marker, covalently bound to human serum albumin (AFL-HSA) [1] 5-aminofluorescein is a pH-sensitive biomaterial, is the targeted prodrug for synthesis of FA-FITC-Arg-PTX and FA-5AF- Glu-PTX.

5-Aminofluorescein,3326-34-9,5-AF,Natural Products, buy 5-Aminofluorescein , 5-Aminofluorescein supplier , purchase 5-Aminofluorescein , 5-Aminofluorescein cost , 5-Aminofluorescein manufacturer , order 5-Aminofluorescein , high purity 5-Aminofluorescein