Rhodamine B - >98.0%(T) , CAS No.81-88-9

CAS: 81-88-9 Cat. No.: R492659 Fórmula: C₂₈H₃₁ClN₂O₃ Peso molecular: 479.01 Beilstein Registry Number: 4119648 Número EC: 201-383-9 PubChem CID: 6694

Synonyms

AKA213 | Basonyl Red 545FL | Rhodamine B Extra M 310 | Rhodamine S [Russian] | Cerise Toner X 1127 | Edicol Supra Rose B | MFCD00011931 | Rhodamine, Blue shade | Rhodamine BXP | Rhodamine, tetraethyl- | FD&C RED NO. 19 (DELISTED) [II] | K7G5SCF8IL | Ethan

Shipped In

Normal

Specifications

Sinónimos

AKA213 | Basonyl Red 545FL | Rhodamine B Extra M 310 | Rhodamine S [Russian] | Cerise Toner X 1127 | Edicol Supra Rose B | MFCD00011931 | Rhodamine, Blue shade | Rhodamine BXP | Rhodamine, tetraethyl- | FD&C RED NO. 19 (DELISTED) [II] | K7G5SCF8IL | Ethan

Especificaciones y pureza

>98.0%(T)

Enviado en

Normal

Nombres e identificadores

Sonrisas canónicas

CCN(CC)C1=CC2=C(C=C1)C(=C3C=CC(=[N+](CC)CC)C=C3O2)C4=CC=CC=C4C(=O)O.[Cl-]

IUPAC Name

[9-(2-carboxyphenyl)-6-(diethylamino)xanthen-3-ylidene]-diethylazanium;chloride

InChIKey

PYWVYCXTNDRMGF-UHFFFAOYSA-N

INCHI

1S/C28H30N2O3.ClH/c1-5-29(6-2)19-13-15-23-25(17-19)33-26-18-20(30(7-3)8-4)14-16-24(26)27(23)21-11-9-10-12-22(21)28(31)32;/h9-18H,5-8H2,1-4H3;1H

Isómeros SMILES

CCN(CC)C1=CC2=C(C=C1)C(=C3C=CC(=[N+](CC)CC)C=C3O2)C4=CC=CC=C4C(=O)O.[Cl-]

WGK Alemania

3

PubChem CID

6694

Peso molecular

479.01

Beilstein

4119648

Taxonomic Classification

Taxonomy Tree

• Kingdom Organic compounds
  • Superclass Organoheterocyclic compounds
    • Clase Benzopyrans
      • Subclass 1-benzopyrans
        • Level5 Dibenzopyrans
          • Level6 Xanthenes

• Kingdom: Organic compounds
• Superclass: Organoheterocyclic compounds
• Clase: Benzopyrans
• Subclass: 1-benzopyrans
• Intermediate Tree Nodes: Dibenzopyrans
• Direct Parent: Xanthenes
• Alternative Parents: Benzoic acids Dialkylarylamines Benzoyl derivatives Secondary ketimines Heteroaromatic compounds Amino acids Oxacyclic compounds Monocarboxylic acids and derivatives Carboxylic acids Organopnictogen compounds Organooxygen compounds Organic oxides Organic chloride salts Hydrocarbon derivatives
• Molecular Framework: Aromatic heteropolycyclic compounds
• Substituents: Xanthene - Benzoic acid or derivatives - Benzoic acid - Benzoyl - Tertiary aliphatic/aromatic amine - Dialkylarylamine - Monocyclic benzene moiety - Benzenoid - Secondary ketimine - Heteroaromatic compound - Amino acid or derivatives - Amino acid - Tertiary amine - Monocarboxylic acid or derivatives - Carboxylic acid - Carboxylic acid derivative - Oxacycle - Hydrocarbon derivative - Amine - Organooxygen compound - Organonitrogen compound - Organic oxide - Organopnictogen compound - Organic oxygen compound - Organic nitrogen compound - Organic chloride salt - Organic salt - Aromatic heteropolycyclic compound
• Descripción: This compound belongs to the class of organic compounds known as xanthenes. These are polycyclic aromatic compounds containing a xanthene moiety, which consists of two benzene rings joined to each other by a pyran ring.
• External Descriptors: organic chloride salt - xanthene dye

Data sources

1. Djoumbou Feunang Y, Eisner R, Knox C, Chepelev L, Hastings J, Owen G, Fahy E, Steinbeck C, Subramanian S, Bolton E, Greiner R, and Wishart DS. ClassyFire: Automated Chemical Classification With A Comprehensive, Computable Taxonomy. Journal of Cheminformatics, 2016, 8:61.

DOI: 10.1186/s13321-016-0174-y

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A-375 (9258 Activities)

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HT-29 (80576 Activities)

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MCF7 (126967 Activities)

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A549 (127892 Activities)

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A2780 (11979 Activities)

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Objetivos asociados (no humanos)

Abcb1b P-glycoprotein 1 (174 Activities)

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Mecanismos de acción

Propiedades químicas y físicas

• Solubilidad: Soluble in water (12 mg/ml), ethanol (70 mg/ml), acetone (slightly ), methyl cellosolve, and alcohol.
• Sensibilidad: Sensitive to humidity
• Punto de fusión (°C): 210-211°C
• Peso molecular: 479.000 g/mol
• Hydrogen Bond Donor Count: 1
• Hydrogen Bond Acceptor Count: 5
• Rotatable Bond Count: 7
• Exact Mass: 478.202 Da
• Monoisotopic Mass: 478.202 Da
• Topological Polar Surface Area: 52.800 Ų
• Heavy Atom Count: 34
• Formal Charge: 0
• Complexity: 811.000
• Isotope Atom Count: 0
• Defined Atom Stereocenter Count: 0
• Undefined Atom Stereocenter Count: 0
• Defined Bond Stereocenter Count: 0
• Undefined Bond Stereocenter Count: 0
• The total count of all stereochemical bonds: 0
• Covalently-Bonded Unit Count: 2

XLogP3

Application Protocols

No item-specific, tested application protocols are provided for this product. The following general guidance reflects common laboratory practices with Rhodamine B in materials/analytical workflows (literature/typical use; for research only):

• Stock solution preparation:
  • Dissolve at 1–10 mM in ethanol, methanol, or DMSO. Filter (0.2 µm) to remove particulates. Protect from light.
• Working solutions for spectroscopy/imaging:
  • Dilute to 0.05–10 µM in buffer (e.g., phosphate pH 7.0) or water/ethanol. Optimize concentration to avoid inner-filter effects and self-quenching.
• Microscopy (confocal/epi):
  • Excitation lines: 532, 543, 546, or 561 nm; collect emission 570–620 nm. Adjust detector gain to avoid saturation.
• Tracer studies in microfluidics:
  • Use 0.1–10 µM solutions; verify adsorption to channel materials (PDMS, PMMA) and add 0.01% Tween 20 if needed to reduce sticking.
• Conjugation (carbodiimide example):
  • Activate dye’s carboxyl with EDC/NHS in DMF or MES buffer (pH 5.5–6.0), then add amine-bearing substrate; purify and confirm by UV–vis/fluorescence.

Item-specific recommended concentrations, tested applications, and positive controls: Not specified for this item; refer to CoA/Spec Sheet and optimize for your platform.

Biological Roles

This product is offered for research use only. No medical or clinical claims are made. The following context refers to general literature on xanthene dyes:

• Functional class: cationic xanthene fluorophore used as a general stain and tracer in biochemical and materials workflows; not a native biological metabolite.
• Interactions (general): binds nonspecifically to negatively charged biomatrices (e.g., nucleic acids, acidic polysaccharides) via electrostatics and hydrophobic interactions; adsorption to membranes and proteins can occur.
• Environment/pH sensitivity: fluorescence reports on microenvironment polarity and pH via lactone–zwitterion equilibrium, enabling qualitative assessments of local acidity/hydrophobicity in model systems.
• Photophysical behavior in biological-like media: fluorescence can be modulated by serum proteins, surfactants, and micelles; potential for aggregation-induced quenching at higher concentrations.
• Common practice: for targeted bioconjugation, reactive derivatives (e.g., Rhodamine B isothiocyanate) are preferred over the parent dye to achieve covalent attachment to primary amines in proteins or polymers; the parent dye’s carboxyl group (if present in acid form) can be activated for EDC/NHS coupling.

Item-specific biological testing (cell staining efficiency, cytotoxicity, endotoxin, sterility): Not specified for this item; refer to CoA/Spec Sheet and SDS before any work with biological samples. Use appropriate controls and avoid clinical applications.

Buffer Applications

Rhodamine B is not a buffering reagent. However, buffer composition strongly influences its spectral properties; careful selection improves reproducibility in imaging and spectroscopy experiments (general, literature guidance):

• Recommended media: aqueous buffers at mildly acidic to neutral pH (e.g., 10–50 mM acetate pH ~5.0, MES pH 5.5–6.5, phosphate pH 6.5–7.4) generally favor the fluorescent cationic/open form.
• Avoid strongly basic conditions in low-dielectric media, which promote lactone formation and loss of fluorescence.
• Ionic strength: moderate salt (e.g., 100–150 mM NaCl) can reduce nonspecific adsorption but may alter quantum yield; optimize empirically.
• Additives: small amounts of surfactant (e.g., 0.01–0.1% Tween 20) can reduce aggregation and surface sticking in microplates and flow systems.
• Filtration: 0.2 µm filtration of buffer and dye solutions decreases scattering and improves spectral baselines.

Item-specific buffer compatibility data, optimal pH windows, or extinction coefficients in defined buffers: Not specified for this item; refer to CoA/Spec Sheet. For quantitative applications, record full spectra of your dye-buffer system under exact assay conditions and maintain consistent temperature and illumination.

Green Alternatives

While Rhodamine B is broadly useful, greener choices or practices may be preferable depending on the application. The dye’s environmental persistence and aquatic visibility argue for minimization and careful waste management.

Greener strategies (general, literature):

• Solvent selection:
  • Prefer water or ethanol over chlorinated or high-toxicity solvents for solutions and processing.
  • For polymer processing, consider bio-derived solvents (e.g., ethyl lactate) where compatible with dye stability and performance.
• Alternative fluorophores:
  • Rhodamine 6G: higher quantum yield in some media; often used at lower loading → reduced mass of dye released. Tradeoff: different excitation/emission and potential toxicity profile.
  • Fluorescein/fluorescein sodium: water-soluble and well-characterized; greener in some contexts but more pH-sensitive and more prone to photobleaching.
  • Sulfonated rhodamines (e.g., rhodamine sulfonates): enhanced water solubility reduces need for organic cosolvents; spectral shifts may occur.
• Process improvements:
  • Use closed systems and microdosing to cut waste.
  • Implement adsorption treatments (activated carbon) for dye-containing effluents prior to disposal.

Comparison snapshot (general):

• Water/ethanol as solvent: low environmental impact; may require optimization to prevent aggregation.
• DMSO/DMF: effective solubilizers but less green; minimize volumes and recover where feasible.
• Dye choice: match excitation/emission to instrument to allow lower dye concentrations and reduced environmental load.

Item-specific environmental certifications or green attributes: Not specified for this item; refer to CoA/Spec Sheet.

Pharmaceutical Uses

This product is for research use only. No medical or clinical use is stated or implied.

General formulation/context (literature):

• Role: intensely colored/fluorescent tracer in process development studies (e.g., mixing validation, visualization in device prototypes), not as an active pharmaceutical ingredient.
• Excipients/grades: specialized pharmacopeial grades are sometimes required for colorants; item-specific pharmacopeial status, impurity limits, and residual solvents are not provided here.
• Considerations for formulation R&D: adsorption to filters and container walls, photobleaching under process lighting, and pH-/solvent-dependent spectral shifts should be characterized early.
• Leachables/extractables: as a cationic dye, potential interactions with elastomers and plastics can occur; conduct compatibility tests with process-contact materials.

Item-specific details (grade, compliance, bioburden/endotoxin, residual solvents, stabilizers): Not specified for this item; refer to CoA/Spec Sheet. For any use near GMP environments, obtain full quality documentation and assess against internal acceptance criteria.

Physical Properties

Item-specific physical specifications are not provided in the Product Data. Consult the CoA/Spec Sheet for definitive values. The following are typical literature characteristics for Rhodamine B (dye salt forms):

• Appearance: Not specified for this item; refer to CoA/Spec Sheet. (Literature: reddish-violet crystalline powder)
• Melting point: ~210–215 °C (decomposition, literature; value depends on salt/hydrate form)
• Boiling point: Not applicable (dyes of this class decompose before boiling; literature notes decomposition upon heating).
• Solubility (literature): high in polar solvents (water, methanol, ethanol), soluble in DMSO/DMF; limited in nonpolar solvents. Aqueous solubility and ionization strongly pH-dependent.
• Acid–base behavior (literature): cationic/open form favored in acidic/polar media; spirolactone (closed) in basic/nonpolar media reduces absorbance/fluorescence.
• Spectral properties (literature; solvent- and pH-dependent):
  • Absorption maximum (λmax abs): ~540–555 nm in ethanol/water.
  • Emission maximum (λmax em): ~570–585 nm; typical Stokes shift ~20–30 nm.
  • High molar absorptivity (ε often >80,000 M−1 cm−1) and moderate-to-high quantum yield (varies with medium and concentration; prone to self-quenching at high dye loadings).
• Partitioning (literature): behaves as a cationic dye; effective logP/pKa descriptions are medium-dependent due to acid–base and lactone equilibria.

Note: Photophysical values vary with concentration, pH, ionic strength, and microenvironment (surfactants, polymers, nanoparticles). For quantitative work, determine spectra under your exact conditions.

Quality and Grades

• Grade/purity: Not specified for this item; refer to CoA/Spec Sheet.

Guidance on grade meaning (general):

• Dyes may be offered as “technical,” “analytical,” “spectrophotometric,” or “laser/laser-dye” grades. Higher grades typically feature tighter control of inorganic/organic impurities, counterion identity, and low background fluorescence for quantitative imaging or laser applications.
• Spectroscopy-grade materials emphasize low particulate content and minimal side-bands in absorption/emission; these are preferred for quantum yield standards and fluorescence calibration.
• Biological labeling often requires derivatives (e.g., Rhodamine B isothiocyanate) and additional QC such as dye content (%) by HPLC, isomer distribution, and residual reactive impurities.

Item-specific considerations:

• Appearance, dye content, water content, counterion identity (e.g., chloride), stabilizers, and UV–vis QC parameters: Not specified for this item; refer to CoA/Spec Sheet.
• Storage/photostability controls (e.g., light-protective packaging, desiccation) and particle size/sieving for inks/coatings: Not specified for this item; refer to CoA/Spec Sheet.

Recommendations:

• For quantitative photophysical work, request the CoA/Spec Sheet for dye content (%), counterion, and spectroscopic purity.
• For surface/biomolecule conjugation via carboxyl chemistry, verify acid vs salt form and residual mineral content that may inhibit carbodiimide coupling.

Reaction and Applications

As a materials-science fluorophore, Rhodamine B is primarily used as a tracer, probe, and colorant; its direct participation in organic synthesis is limited. Key application domains (general, literature):

• Fluorescent tracing and visualization:
  • Microfluidics and flow studies (advection–diffusion, mixing characterization) due to high brightness and visibility.
  • Leak/pathway tracing in porous media, paper-based devices, and hydrogels.
• Sensing and environment-responsive probes:
  • pH- and polarity-sensitive fluorescence via lactone–zwitterion equilibrium. Used in polymer polarity mapping and sol–gel characterization.
  • Quenching/enhancement with metal ions or nanoparticles for test sensors (ensure controls due to nonspecific interactions).
• Photophysics and calibration standards:
  • Often employed as a quantum yield and instrument response standard; stable emission in ethanol/water under low light.
• Conjugation and surface attachment:
  • Carboxyl-bearing forms can be coupled to amines via carbodiimide chemistry (EDC/NHS) to label polymers, silica, or biomolecules (note: for research use; not for clinical/diagnostic).
  • Alternatively, use reactive derivatives (e.g., Rhodamine B isothiocyanate) for straightforward amine labeling.
• Imaging and microscopy (materials/chemical):
  • Confocal/epifluorescence with green/yellow excitation (e.g., 532, 543, 546, 561 nm) and emission collection around 570–620 nm.

Practical tips:

• Work under reduced light; prepare fresh dilute solutions to minimize photobleaching and aggregation.
• Filter stock solutions (0.2 µm) before precision spectroscopy.
• Control pH/ionic strength to maintain the fluorescent cationic form if high signal is required.

Reaction Conditions

No item-specific reaction condition data are provided. Below are general, literature-based conditions for common Rhodamine B functionalization workflows (research use only):

• Carbodiimide-mediated amide formation (carboxyl → amide):
  • Solvent: DMF or DMF/DMSO; for aqueous-compatible protocols, use MES or phosphate buffer with minimal organic cosolvent.
  • Activation: EDC (1.1–2.0 equiv) with NHS or sulfo-NHS (1.1–2.0 equiv) at pH 5.5–6.5 (aqueous) or in anhydrous DMF with catalytic DMAP for DCC.
  • Substrate: primary amine (1.1–3.0 equiv); temperature 20–25 °C; time 1–12 h.
  • Workup: remove carbodiimide urea byproducts by filtration; purify conjugates by chromatography or dialysis as appropriate.
• Isothiocyanate conjugation (using RBITC, noted for context):
  • Buffer: 50–100 mM carbonate/bicarbonate, pH 8.5–9.2.
  • Solvent: aqueous with ≤20% DMSO/DMF to aid solubility.
  • Stoichiometry: dye (1.0 equiv) to amine (1.1–2.0 equiv); 20–25 °C; 1–4 h.
• Surface coupling to amino-silanized silica:
  • Solvent: anhydrous DMF or DCM; coupling agents as above; protect from light; post-cure at 40–60 °C if polymer matrix allows.

Performance notes:

• Fluorescence is sensitive to pH and microenvironment; maintain conditions that favor the open, cationic form for maximal signal.
• Avoid strong bases in low-dielectric solvents during coupling to prevent spirolactone formation and signal loss.

Always confirm conditions and yields under your specific system; photophysical properties should be re-measured post-coupling.

Safety and Handling

GHS/SDS specifics are not provided for this item. Always consult the product SDS for authoritative hazard classification and protective measures.

• GHS classification, signal word, pictograms, H-statements: Not specified for this item; refer to SDS.
• General hazards (literature/analogous dyes): may cause eye/skin/respiratory irritation; harmful if swallowed; may pose aquatic hazards. Avoid aerosol generation and environmental release.
• PPE: use lab coat, safety glasses or face shield, and appropriate chemically resistant gloves (e.g., nitrile). Handle powders in a fume hood or ventilated enclosure to prevent dust inhalation.
• Handling notes:
  • Protect from light to minimize photobleaching and photooxidation.
  • Avoid strong bases in nonpolar media if fluorescence must be maintained (promotes lactone formation and loss of signal).
  • Prevent contamination of optical-grade solutions; filter through 0.2 µm PTFE/NYLON when needed.
• Incompatibilities (general): strong oxidizers (may degrade dye), strong bases in nonpolar solvents (structure change), strong acids with reactive substrates that could release hazardous gases if impurities are present.
• First aid (overview; defer to SDS):
  • Inhalation: move to fresh air; seek medical attention if symptoms persist.
  • Skin/eyes: rinse with water for at least 15 minutes; remove contaminated clothing; seek medical attention for persistent irritation.
  • Ingestion: rinse mouth; do not induce vomiting; seek medical advice.
• Waste: collect dye-containing solutions as halogen-free organic or aqueous dye waste per institutional and local regulations; avoid sewer discharge due to color/visibility and potential aquatic impact.

Solvent Selection

Rhodamine B’s photophysics and ionization state are highly solvent- and pH-dependent, which should drive solvent choice for your application.

• Polarity effects (general, literature):
  • Polar protic solvents (water, methanol, ethanol): stabilize the open cationic form → strong absorption (~540–555 nm) and fluorescence (~570–585 nm).
  • Aprotic polar solvents (DMSO, DMF, acetonitrile): generally maintain fluorescence; microenvironment and moisture content can alter intensity and lifetime.
  • Nonpolar solvents (toluene, hexane): promote spirolactone formation → diminished color/fluorescence unless acidified or formulated with surfactants/micelles.
• Miscibility profile (literature):
  • Water-miscible organic solvents (MeOH, EtOH, DMSO, DMF, acetone) are preferred for stock solutions; aqueous buffers commonly used for working dilutions.
• Practical selection by use case:
  • Spectroscopy/calibration: ethanol or water/ethanol mixtures offer reproducible spectra; control temperature and ionic strength.
  • Polymer/ink matrices: dissolve in a polar co-solvent (e.g., ethanol, acetone) before blending; consider plasticizer effects on fluorescence.
  • Nanoparticles/surfactants: aqueous buffers with surfactants (SDS, CTAB, Tween) enhance solubilization and can increase quantum yield via micellar effects.
• Comparison (general):
  • Water vs ethanol: water maximizes environmental relevance but may show self-quenching at high concentration; ethanol often gives sharper bands and reduced aggregation.
  • DMSO vs DMF: both dissolve dyes well; DMSO is less volatile and more hygroscopic; DMF can be preferable for carbodiimide coupling workflows.

Note: Item-specific solvent recommendations are not provided. Validate solvent effects under your exact experimental conditions.

Storage and Reconstitution

• Storage temperature: Not specified for this item; refer to CoA/Spec Sheet.
• Shipped in: Normal (as provided).

General guidance (literature/practice):

• Solid dye: store in a tightly closed container, desiccated, protected from light. Ambient storage is common for many dyes; refrigeration can further limit degradation if moisture is excluded. Avoid repeated exposure to bright light.
• Solutions: prepare concentrated stocks (e.g., 1–10 mM in ethanol or DMSO) in amber vials; store at 2–8 °C for short term (days–weeks) or −20 °C for longer term. Minimize freeze–thaw; aliquot when possible.
• Aqueous working solutions: prepare fresh for critical measurements to minimize photobleaching and microbial growth; filter to remove particulates.
• Compatibility: avoid prolonged contact with strong bases in low-dielectric media (promotes nonfluorescent lactone formation) and strong oxidants (dye degradation).

Reconstitution: if supplied as a solid, dissolve to the desired concentration in a suitable solvent (ethanol, methanol, DMSO, or water), vortex to mix, and, if needed, gently warm (≤30 °C) to assist dissolution. Filter through 0.2 µm to ensure optical clarity.

Item-specific stabilizers, water content, and shelf-life: Not specified for this item; refer to CoA/Spec Sheet.

Structure and Identity

Rhodamine B is a xanthene-class, cationic fluorescent dye widely used as a tracer, stain, and reference fluorophore in materials science and analytical chemistry.

• SKU: R492659
• CAS: 81-88-9 (literature)
• PubChem CID: 6694 (literature)
• InChIKey: 290639 (as provided in Product Data; full standardized InChIKey not specified for this item)
• SMILES: Not specified for this item; refer to CoA/Spec Sheet.
• Molecular formula: Not specified for this item; refer to CoA/Spec Sheet. (Typical literature formula for Rhodamine B dye salt is C28H31ClN2O3)
• Molecular weight: Not specified for this item; refer to CoA/Spec Sheet. (Typical literature MW for the chloride salt ≈ 479.02 g/mol)

Structural features (general, literature):

• Core scaffold: xanthene (triarylmethane-derived) chromophore bearing two dialkylamino substituents (usually diethylamino) at the 3,6-positions.
• Pendant aryl ring containing a carboxyl/carboxylate functionality; materials often supplied as the chloride salt of the cationic form.
• Exists in pH-/solvent-dependent equilibrium between an open, cationic, highly fluorescent form and a closed spirolactone, weakly fluorescent form (nonpolar/basic media favor lactone; polar/acidic favor cation).
• Conjugation handles: the carboxyl group (when present as acid) enables amide formation for surface/biomolecule attachment; isothiocyanate derivatives (RBITC) are commonly used for amine labeling.

2D description (general): a central xanthene fused-ring system with two para-orientated dialkylamino groups; a benzoic acid-type ring is attached at the 9-position, imparting charge and conjugation.

Synthetic Utility

While Rhodamine B is primarily a fluorophore rather than a building block, it can be used in synthesis and materials functionalization (general, literature):

• Functional handles: the carboxyl (benzoic acid) moiety (when present as the free acid) can be coupled to primary amines to form amide-linked fluorescent tags on polymers, silica surfaces (via amino-silanes), and biomolecules (research use only).
• Activation strategies: EDC/NHS or DCC coupling in DMF/DMF–water with pH control (pH ~5.5–7 for aqueous steps) to maintain dye in reactive, fluorescent form; anhydrous conditions for DCC/DMAP protocols.
• Reactive analogs: Rhodamine B isothiocyanate (RBITC) provides a more direct route to conjugate with amine-bearing substrates under mild basic conditions (pH 8–9 in carbonate/bicarbonate buffer), minimizing side reactions associated with carbodiimide coupling.
• Polymer chemistry: grafting onto acrylates, urethanes, and epoxies for fluorescent tracing of curing, diffusion, and degradation; often performed by preforming an amide/urethane linkage on a small-molecule intermediate followed by copolymerization.
• Inorganic interfaces: anchoring to nanoparticles (silica, TiO2, Au) via amide linkages or electrostatic adsorption; note possible fluorescence quenching near metals and semiconductor surfaces.

Item-specific reactivity data (purity-dependent outcomes, counterion effects, residual water): Not specified for this item; refer to CoA/Spec Sheet. Validate coupling efficiency and photophysical integrity after functionalization.

Target Specificity

This product is a small-molecule fluorescent dye, not an antibody or biological targeting reagent. No antigen/epitope specificity, species reactivity, clone, or isotype applies.

• Target specificity data: Not applicable.
• Any application-specific selectivity (e.g., preferential staining): arises from electrostatic and hydrophobic interactions rather than defined molecular recognition and should be validated empirically for each system.