950846-89-6

Basic information

• Product Name: 2-(2-aminoethyl) Rhodamine B amide
• Synonyms: 2-(2-aminoethyl) Rhodamine B amide;N-(rhodamine-B)lactam-1,2-ethylenediamine;2-(2-aminoethyl)-3',6'-bis(diethylamino)spiro[isoindoline-1,9'-xanthen]-3-one
• CAS NO: 950846-89-6
• Molecular Formula: C₃₀H₃₆N₄O₂
• Molecular Weight: 484.63244
• Mol File: 950846-89-6.mol
• Article Data: 129

Chemical Properties

• Melting Point: 217-219 °C
• Boiling Point: 676.5±55.0 °C(Predicted)
• Appearance: /
• Density: 1.24±0.1 g/cm3(Predicted)
• Storage Temp.: Room Temperature, under inert atmosphere
• Solubility: Chloroform (Slightly)
• PKA: 8.82±0.10(Predicted)
• CAS DataBase Reference: 2-(2-aminoethyl) Rhodamine B amide(CAS DataBase Reference)
• NIST Chemistry Reference: 2-(2-aminoethyl) Rhodamine B amide(950846-89-6)
• EPA Substance Registry System: 2-(2-aminoethyl) Rhodamine B amide(950846-89-6)

Safety Data

• Hazardous Substances Data: 950846-89-6(Hazardous Substances Data)

Usage

General Description

2-(2-Aminoethyl) Rhodamine B amide is a fluorescent dye that is often used in biological research and imaging applications. It is a derivative of Rhodamine B, a red fluorescent dye, that has been modified with an aminoethyl group. This modification allows the dye to be conjugated to proteins and used for labeling and visualization of specific targets in cells and tissues. In addition to its fluorescence properties, 2-(2-Aminoethyl) Rhodamine B amide has also been utilized in the development of diagnostic assays and as a probe for studying cellular function and intracellular trafficking. Overall, this compound has proven to be a valuable tool in the field of biological and biomedical research.

Upstream product

• 509-34-2 rhodamine B 
• 107-15-3 ethylenediamine 
• 81-88-9 rhodamine B 
• 111-40-0 3-azapentane-1,5-diamine 
• 4344-42-7 rhodamine B 
• 1118784-85-2 rhodamine B 
• 1118426-88-2 rhodamine B hydrochloride 
• 69319-23-9 rhodamine B 

Downstream Products

• 1574486-45-5 Rhodamine B 
• 287401-73-4 {9-[2-(2-amino-ethylcarbamoyl)-phenyl]-6-diethylamino-xanthen-3-ylidene}-diethyl-ammonium 
• 1313741-45-5 C₄₁H₅₁N₅O₂ 
• 1313741-44-4 C₃₇H₄₂N₄O₃ 
• 1370596-03-4 C₃₇H₄₁BrN₄O₂ 

Relevant articles and documents

Rapid detection of mercury (II) ions and water content by a new rhodamine B-based fluorescent chemosensor

A rhodamine B-based sensor (RS) was designed and synthesized by a combination of the spirolacton rhodamine B (fluorophore) and multidentate chelates (ionophore) with high affinity towards Hg2+. In the presence of Hg2+, the resulting red-orange fluorescence (under UV light) and naked eye red color of RS are supposed to be used for quantitative and qualitative measurement of Hg2+. Further fluorescent titration and analysis demonstrate that RS can selectively detect Hg2+ within 1 s with a low limit of detection (LOD) of 16 nM in acetonitrile media, meanwhile, the association constant (Ka) was calculated to be 0.32 × 105 M?1. More importantly, the resultant complex (RSHg) of RS and Hg2+ has also been successfully applied to detect limited water content in acetonitrile solution.

A new Rhodamine B-based 'on-off' chemical sensor with high selectivity and sensitivity toward Fe3+ and its imaging in living cells

A new fluorescent chemosensor based on a Rhodamine B and pyrrole conjugate (RBPY) has been designed and synthesized. UV-vis absorption and fluorescence spectroscopic studies show that RBPY exhibits a high selectivity and sensitivity toward Fe3+ among many other metal cations in a MeOH/H2O solution (3:2, v/v, pH 7.10, HEPES buffer, 0.1 mM) by forming a 1:1 complex with Fe3+. Furthermore, results reveal that the formation of the RBPY-Fe3+ complex is fully reversible in the presence of sulfide anions and could also be used as an efficient sensor for S2-. Importantly, fluorescence microscopy experiments further demonstrated that RBPY can be utilized as a fluorescent probe for the detection of Fe3+ in human liver (L-02) cells.

Insights into the phenomenon of acquisition and accumulation of Fe3+ in Hygrophila spinosa through fluorimetry and fluorescence images

Rhodamine functionalized fluorescent probe IP has been synthesized to investigate the phenomenon of Fe3+ acquisition and accumulation in Hygrophila spinosa. H. spinosa is a tropical medicinal plant which is iron rich and consumed for the treatment of the patients suffering from anaemia. IP is capable of selectively binding Fe3+ by enhancing fluorescent intensity via “turn on” mechanism due to complex formation. Spectroscopic studies and microscopic tools helped in better understanding about the acquisition as well as the quantitative accumulation of Fe3+ in different parts of the plant.

Mechanically controlled FRET to achieve high-contrast fluorescence switching

Organic luminescent materials with the ability to reversibly switch the luminescence when subjected to external stimuli have attracted considerable interest in recent years. However, luminescent materials with mechanochromic and photochromic dual-responsi

A new highly sensitive and selective fluorescence chemosensor for Cr 3+ based on rhodamine B and a 4,13-diaza-18-crown 6-ether conjugate

A rhodamine B-based sensor consisting of two rhodamine B moieties linked to the two amine sides of a 4,13-diaza-18-crown-6 ether was synthesized as a highly sensitive fluorescent probe for monitoring Cr3+ in a MeOH-H2O (3 : 2, v/v, pH 7.2) solution and in living cells.

A FRET-based ratiometric sensor for mercury ions in water with multi-layered silica nanoparticles as the scaffold

A FRET system was built for ratiometric sensing of Hg2+ in water with multilayered silica nanoparticles as the scaffold. This architecture ensures the control over the location of both donor and acceptor and their separation distance within nanoparticles, affording higher energy transfer efficiency and higher signal-to-background ratio for particle-based sensing.

Hybrid polymeric chemosensor bearing rhodamine derivative prepared by sol-gel technique for selective detection of Fe3+ ion

To develop a reusable and selective colorimetric chemosensor for visual detection of ferric ion, a new rhodamine-based chelator (RB-UTES) was prepared. The structural constitution and sensing property of RB-UTES were examined. The chelator was sensitive and selective for recognition of ferric ion and could be covalently attached to poly(vinyl alcohol) through siloxane linkage formed by the sol-gel reaction. The physicochemical properties and sensing behavior of the functional chemosensor films were investigated. By simply soaking in aqueous media, the free-standing sensor film exhibited high selectivity and sensitivity to ferric ion and permitted the convenient detection by naked eye with prominent development of pink color throughout the film. The sensor film could return to its original color by washing with 0.1 M ethylenediamine allowing repeated cycles of detection. The combination of its analytical performance, simplicity of operation as well as reusability made this functional sensor promising for the use in aqueous solutions and real samples.

A bis-(rhodamine)-based off–on colorimetric and fluorescent probe for Fe3+ ion detection in serum and bioimaging

Abstract: An off–on colorimetric and fluorescent probe N1, N4-bis (2-(3′, 6′-bis(diethylamino)-3-oxospiro[isoindoline-1,9′-xanthen]-2-yl) ethyl) terephthalamide (Rp) for Fe3+ was designed and synthesized, which could selectively and sensitively respond to Fe3+ among other tested metal cations in THF–H2O solution (v/v = 4/6, pH = 7.2) accompanied with a remarkable fluorescence enhancement and an obvious color change visible to “naked-eye”. The fluorescence intensity of the probe Rp showed a good linearity with the concentration of Fe3+ covering from 0.1 to 26?μM and the detection limit was 0.0231?μM. Meanwhile, the binding mode between Rp and Fe3+ was found to be a 1:2 stoichiometric formation. Moreover, the complexation of Rp–Fe3+ could be broken by carbonate, so this system might be utilized as a carbonate probe in the future. Most importantly, the probe Rp was not only applied to monitor Fe3+ level in human blood serum and water samples, but also was used for fluorescence imaging of Fe3+ in living cell. Graphical abstract: [Figure not available: see fulltext.].

A ratiometric lysosomal pH probe based on the imidazo[1,5-: A] pyridine-rhodamine FRET and ICT system

A new pH-activatable ratiometric fluorescent probe (RhMP) has been developed, in which an imidazo[1,5-a]pyridine fluorophore as a fluorescence resonance energy transfer (FRET) donor linked to a rhodamine B fluorophore as a FRET acceptor. The simultaneous fluorescence intensity enhancement of imidazo[1,5-a]pyridine and rhodamine B moieties along with the decrease of pH value should result from the integration of ICT and FRET processes. It's the first time a ratiometric fluorescent probe based on FRET system using imidazo[1,5-a]pyridine derivative as a fluorophore donor has been reported. At pKa = 4.96, the fluorescence intensity ratio (I476.5/I577.5) of the probe displayed excellent pH-dependent performance and responded linearly to minor pH changes in the range of 4.0-5.8. The probe exhibited excellent selectivity among different metal cations and brilliant reversibility. In addition, RhMP has low cytotoxicity and has been successfully applied in HeLa cells. The fluorescence microscopic images demonstrated this probe could image weak acid pH changes of the lysosome in live cells.

A dipeptide-based multicolored-switching luminescent solid material: When molecular assemblies meet mechanochemical reaction

Color schemes: A mechanochromic material composed of two types of peptides bearing a pyrene group and rhodamine B moieties, respectively, displays multiluminescent colors, such as blue, green, and reddish in one sample (see picture). The mechanochromic behavior is based on a combined switching of molecular assemblies and chemical structure. Copyright

Facile synthesis of rhodamine-based highly sensitive and fast responsive colorimetric and off-on fluorescent reversible chemosensors for Hg2+: Preparation of a fluorescent thin film sensor

Fluorescence-active chemosensors (L1-L4), comprising a rhodamine scaffold and a pseudo azacrown cation-binding subunit, have been proposed and characterized as a fluorescent chemosensor for Hg2+. An on-off type fluorescent enhancement was observed by the formation of the ring-opened amide form of the rhodamine moiety, which was induced by the interactions between Hg2+ and the chemosensor. Upon the addition of Hg2+, an overall emission change of 350-fold was observed, and the selectivity was calculated to be 300 times higher than Cu2+ for receptors L2-L4. A polymeric thin film can be obtained by doping poly(methyl methacrylate) or PMMA with chemosensor L2. Such a thin film sensor can be used to detect Hg 2+ with high sensitivity and can be recovered using diluted NaOH. The Royal Society of Chemistry.

Differential detection and quantification of cyclic AMP and other adenosine phosphates in live cells

A new naphthol-based rhodamine derivative (NpRD) has been developed for the selective and differential detection of adenosine 3′,5′-cyclic monophosphate (cAMP) and adenosine phosphates (APs) (ATP, ADP, and AMP) from other nucleotides. The simple detection and quantification of cAMP in human blood cells and in other samples based on the 'turn on' fluorescence properties of this chemosensor through colorimetry or fluorometry makes it unique for probable application in high throughput screening.

A lysosomal probe for monitoring of pH in living cells and ovarian tumour

Intracellular pH is important in regulating various cellular behaviour and pathological conditions. We synthesised a rhodamine-based lysosomal pH probe (hereafter referred to as RD) with a pKa of 4.10. The probe exhibited favourable “on-off” reversibility

A Novel Water-soluble Ratiometric Fluorescent Probe Based on FRET for Sensing Lysosomal pH

A new ratiometric fluorescent probe based on F?rster resonance energy transfer (FRET) for sensing lysosomal pH has been developed. The probe (RMPM) was composed of imidazo[1,5-α]pyridine quaternary ammonium salt fluorophore as the FRET donor and the rhodamine moiety as the FRET acceptor. It’s the first time to report that imidazo[1,5-α]pyridine quaternary ammonium salt acts as the FRET donor. The ratio of fluorescence intensity of the probe at two wavelengths (I424/I581) changed significantly and responded linearly toward minor pH changes in the range of 5.4–6.6. It should be noted that it’s rare to report that a ratiometric pH probe could detect so weak acidic pH with pKa?=?6.31. In addition, probe RMPM exhibited excellent water-solubility, fast-response, all-right selectivity and brilliant reversibility. Moreover, RMPM has been successfully applied to sensing lysosomal pH in HeLa cells and has low cytotoxicity.

Synthesis and evaluation of a new Rhodamine B and Di(2-picolyl)amine conjugate as a highly sensitive and selective chemosensor for Al3+ and its application in living-cell imaging

A new Rhodamine B derivative (RBDPA), namely, N1-(2-(3′,6′-bis(diethylamino)-3-oxospiro[isoindoline-1,9′-xanthen]-2-yl)ethyl)-N4,N4-bis(pyridin-2-ylmethyl)succinamide, was designed, synthesized and structurally characterized to develop a chemosensor. The studies show that RBDPA exhibits high sensitivity and selectivity toward Al3+ among many other metal cations in an ethanol/H2O (1:1, v/v, pH = 7.2, HEPES buffer, 0.1 mM) solution. Fluorescence microscopy experiments further demonstrate that RBDPA can be used as a fluorescent probe to detect Al3+ in living cells.

Synthesis and evaluation of two novel rhodamine-based fluorescence probes for specific recognition of Fec+ ion

Two low cytotoxic fluorescence probes Rb1 and Rb2 detecting Fe3+ were synthesized and evaluated. Rb1 and Rb2 exhibited an excellent selectivity to Fe3+, which was not disturbed by Ag+, Li+, K+, Na+, NH4+, Fe2+, Pb2+, Ba2+, Cd2+, Ni2+, Co2+, Mn2+, Zn2+, Mg2+, Hg2+, Ca2+, Cu2+, Ce3+, AcO?, Br?, Cl?, HPO42?, HSO3?, I?, NO3?, S2O32?, SO32? and SO42? ions. The detection limits were 1.87?×?10?7?M for Rb1 and 5.60?×?10?7?M for Rb2, respectively. 1:1 stoichiometry and 1:2 stoichiometry were the most likely recognition mode of Rb1 or Rb2 towards Fe3+, and the corresponding OFF–ON fluorescence mechanisms of Rb1 and Rb2 were proposed.

New fluorescent sensor for antimony and transition metal cations based on rhodamine amide-arm homotrioxacalix[3]arene

A new fluorescent sensor 1 based on the rhodamine amide-armed homotrioxacalix[3]arene was synthesized, and its sensing behavior toward metal ions was investigated by UV-vis and fluorescence spectroscopies. Upon the addition of metal cations (Sb3+, Fe3+, Ni2+), a significant fluorescent enhancement in the range of 500-600 nm and colorimetric change was observed. Springer Science+Business Media B.V. 2009.

Rhodamine-based bis-sulfonamide as a sensing probe for Cu2+ and Hg2+ ions

A new rhodamine-based bis-sulfonamide 1 has been designed and synthesized. The receptor selectively recognizes Cu2+ and Hg2+ ions in CH3CN-water (4/1, v/v; 10 μM tris HCl buffer, pH 6.8) by showing different emission characteristics and color changes. While Cu2+ is sensed through increase in emission, Hg2+ is detected by a weak ratiometric change in emission of 1. The receptor shows in vitro detection of both the ions in human cervical cancer (HeLa) cells.

Highly selective fluorescent probe based on a rhodamine B and furan-2-carbonyl chloride conjugate for detection of Fe3+ in cells

A furan-2-carbonyl chloride modified rhodamine B derivative (RBFC) has been designed and synthesized. The probe RBFC exhibited excellent sensitivity and selectivity for detection of Fe3+ with a 1:1 stoichiometry over other tested metal ions in a MeOH/H2O (1:1, v/v, pH 7.36, HEPES buffer, 1.3 mM) solution. The association constant and the detection limit were calculated to be 7.28 × 103 M?1 and 0.437 μM based on fluorescence titration analysis. Furthermore, the probe RBFC was successfully applied in living cells, and the results indicated that the probe could monitor intracellular Fe3+ in MCF-7 cells.

Cu(II)-selective green fluorescence of a rhodamine-diacetic acid conjugate

A new rhodamine derivative (1) containing an ethylenediamine-N,N-diacetic acid moiety exhibits Cu(II)-selective strong green fluorescence, while showing very weak orange fluorescence with other metal cations.

Synthesis and evaluation of a novel ‘off-on’ chemical sensor based on rhodamine B and the 2,5-pyrrolidinedione moiety for selective discrimination of glutathione and its bioimaging in living cells

A new “turn-on” fluorescent probe, RDMBM, based on the rhodamine B dye and the 2,5-pyrrolidinedione moiety was synthesized and characterized. Its sensing behavior toward various amino acids was evaluated via UV–vis and fluorescence spectroscopic techniques. The observed spectral changes showed that RDMBM displays high selectivity and sensitivity toward GSH in MeOH/H2O (1:2, v/v, pH 7.40, Tris-HCl buffer, 1 mM) solution and that it undergoes 1:1 covalent binding with GSH. More importantly, the hydrogenation and ring-opening of the nitrogen atom in the spirane structure of rhodamine B derivatives were tightly bound to the induction effects of different groups. Furthermore, fluorescence imaging applications demonstrated that RDMBM can be successfully used for the detection of GSH in human breast cancer cells MCF-7.

A pH optical and fluorescent sensor based on rhodamine modified on activated cellulose paper

A rhodamine-based colorimetric and fluorescent pH chemosensor (RhA) was designed and synthesized via a coupling reaction between rhodamine ethylenediamine and succinic anhydride. RhA showed excellent pH response in aqueous solutions. In addition, common cations (Na+, K+, Ag+, Mg2+, Ca2+, Pb2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Hg2+, Al3+, Cr3+, Fe3+, Au3+, Pt2+, and Ru2+) did not interfere with the pH response. As it has the potential to be used as a portable pH sensor, RhA was immobilized on activated cellulose paper using N,N'-dicyclohexylcarbodiimide (DCC) and N,N'-dimethylpyridin-4-amine (DMAP) as the coupling reagent to obtain a composite pH sensor (CP-RhA). CP-RhA was characterized by ATR-FTIR, UV–vis, and fluorescence spectroscopy, and by scanning electron microscopy (SEM). CP-RhA showed a rapid response in the pH range 1–8 through color and fluorescence changes. DFT calculations showed a blue-shifted spectrum in the protonated form compared to the neutral form. Moreover, the pH sensor paper could be reused by dipping in NaOH. Thus, our work demonstrates the potential of the rhodamine dye composite for visualizing pH changes in real systems.

Hg(II) ion specific dual mode signalling in a thiophene derivatized rhodamine based probe and their complexation cooperativity

The rhodamine based chemosensor 1 exhibited highly selective and sensitive detection of Hg(II) ion in MeCN-H2O mixture observable through amplified absorption and emission signals with a colour change from colourless to pink. Its thiophenyl subunit plays a predominant role in observed allosteric cooperativity in binding of both the Hg(II) ions of its 1:2 (L:M) complex stoichiometry. The anion induced 'turn-off' signalling responses of the Hg(II)-complex of 1 and subsequent 'turn-on' responses with further addition of Hg(II) here demonstrated its repetitive usability as a probe for Hg(II) ion detection.

Water induced chromogenic and fluorogenic signal modulation in a bi-fluorophore appended acyclic amino-receptor system

An acyclic amino-receptor based bi-fluorophoric signaling system 3 exhibits water-induced simultaneous dual channel chromogenic and fluorogenic signal modulation. Its micromolar solution in various organic solvents exhibits an enhancement in absorption in the presence of water in trace amounts through the water-induced delactonization of rhodamine dye, rendering a visual perception as a function of colour change. The presence of water molecules also facilitates a fluorescence resonance energy transfer (FRET) from the excited nitro-benz-oxa-diazole fluorophore to rhodamine dye of 3 and leads to an enhancement of emission up to a second order of magnitude. The failure of the reference compounds 2 and 4 to respond under similar conditions reveals the role of structural variation of the receptor on the perturbation of photophysical processes.

A Dual-Modal SERS/Fluorescence Gold Nanoparticle Probe for Mitochondrial Imaging

A novel SERS/fluorescent multimodal imaging probe for mitochondria has been synthesised using 12 nm diameter gold nanoparticles (AuNP) surface functionalised with a rhodamine thiol derivative ligand. The normal pH-dependent fluorescence of the rhodamine-based ligand is inversed when it is conjugated with the AuNP and higher emission intensity is observed at basic pH. This switch correlates to a pKa at pH 6.62, which makes it an ideal candidate for a pH-sensitive imaging probe in the biological range (pH 6.5–7.4). The observed pH sensitivity of the ligand when attached to the AuNP is thought to be due to the formation of a spirolactam ring, going from positively charged (+18 mV) to negatively charged (?60 mV) as the pH is changed from acidic to basic. Additionally, conjugation of the ligand to the AuNP serves to enhance the Raman signal of the rhodamine ligand through surface-enhanced Raman scattering (SERS). Confocal microscopy has shown that the probe enters HEK293 (kidney), A2780 (ovarian cancer) and Min6 (pancreatic beta) cells within an hour and a half incubation time. The probe was shown to localise in the mitochondria, thus providing a novel pH-dependent SERS/fluorescent multimodal imaging probe for mitochondria.

Recovery Mechanism of Endoplasmic Reticulum Revealed by Fluorescence Lifetime Imaging in Live Cells

Endoplasmic reticulum (ER) is an important organelle of a membranous tubule network in cells for the synthesis, assembly, and modification of peptides, proteins, and enzymes. Autophagy and destruction of ER commonly occur during normal cellular activities. These processes have been studied extensively, but the spontaneous ER regeneration process is poorly understood because of the lack of molecular tools capable of distinguishing the intact, damaged, autophagic, and regenerative ER in live cells. Herein, we report a dual-localizing, environment-responsive, and lifetime-sensitive fluorescent probe for real-time monitoring ER autophagy and regeneration in live cells. Using this tool, the fluorescence lifetime imaging can quantitatively determine the degrees of ER destruction and spontaneous recovery. Significantly, we show that triglycerides supplied in lipid droplets can efficiently repair ER via the two critical pathways: (i) supplying materials for ER repair by converting triglycerides into fatty acids and diglycerides and (ii) partially inhibiting autophagy for stressed ER.

Solvent-dependent selective “naked eye” chromofluorogenic multifunctional rhodamine-based probe for Al3+, Cu2+, Hg2+, S2? and CN? ions

The solvent-dependent selective “naked eye” chromofluorogenic multifunctional rhodamine-based probe 3 for Al3+, Cu2+, Hg2+, S2? and CN? ions was synthesized and its spectral, luminescent and ionochromic properties were studied. The compound obtained exists in the spirolactam form, confirmed by data of 1H, COSY, HSQC, HMBC and 13C NMR spectroscopy. In ethanol, Al3+ ions selectively, even in the presence of other metal cations (Na+, Ba2+, Zn2+, Cd2+, Ni2+, Co2+, Cu2+, Hg2+ and Fe3+) initiate the opening of the spirolactam ring, accompanied by the appearance of a new absorption band at 556 nm and the “naked eye” effect with a change in the yellow-green color of the solution to orange-pink. At the same time, the initial fluorescence 3 at 539 nm shifts to the longer 579 nm spectral region. The use of acetone as a solvent allows the selective detection of copper(II) cations that turn the yellow color of a solution of 3 to pink-purple (λabs 563 nm) due to the formation of the ring-open complex 3.Cu2+ that exhibits emission at 580 nm. Selective detection of Hg2+ in acetonitrile results in the “naked eye” effect characterized by a change in the color of the solution from bright yellow to pink-cherry (λabs 564 nm). The fluorescence of the mercury(II) complex is observed at 587 nm. Complexes 3.Cu2+ and 3.Hg2+ were used for the sequential selective recognition of S2? and CN? anions, respectively. A combinatorial molecular logic gate was designed based on the cation/anion sensing ability of probe 3.