5(6)-SFX ,SE , CAS No.114616-31-8

CAS: 114616-31-8 Cat. No.: S1452259 Formula: C₃₁H₂₆N₂O₁₀ Peso molecolare: 586.546 Numero EC: 635-006-8

Storage

Protected from light,Store at -20°C,Desiccated

Shipped In

Ice chest + Ice pads

Panoramica

5(6)-SFX ,SE (Compound SFX-SE) is a fluorescent dye for labeling primary amines and nascent proteins.

Specifiche

Condizioni di conservazione di stoccaggio

Protected from light,Store at -20°C,Desiccated

Spedito in

Ice chest + Ice pads

Questo prodotto richiede spedizione a catena fredda. I servizi di terra e altri servizi economici non sono disponibili.

Nomi e identificatori

WGK Germania

3

Peso molecolare

586.546

Application Protocols

No tested-application protocols (e.g., WB, IHC, IF, FC) are provided for this item in the Product Data.
• Guidance: Refer to the Reaction Conditions tab for general, literature-based recommendations on NHS-ester labeling of amines. Develop and validate protocols empirically for your specific substrate and instrumentation.

Biological Roles

This product is intended for research use only. No biological/clinical claims are made. The notes below are general background for fluorescein-type dyes (literature/general).
• Fluorophore characteristics: Fluorescein derivatives exhibit bright green fluorescence with pH-dependent spectral properties due to phenolic acid–base equilibria. Ionization state impacts quantum yield and excitation/emission maxima.
• Conjugation to biomolecules: When covalently attached to proteins, peptides, nucleic acids, or small molecules via NHS-ester chemistry, fluorescein serves as a reporter for imaging, assay development, and tracking of biomolecular interactions.
• Photophysics: Typical high extinction coefficients and good quantum yields in neutral to slightly basic aqueous media; fluorescence can be reduced by heavy-atom substituents, aggregation, or contact quenching in densely labeled targets.
• Environmental sensitivity: Fluorescence intensity and lifetime can depend on local polarity, hydrogen bonding, and proximity to quenchers (e.g., tryptophan, electron-rich aromatics), enabling environment-sensitive readouts in biochemical systems.
• Biological compatibility: After conjugation, the net charge and hydrophilicity of the dye–biomolecule conjugate affect solubility, non-specific binding, and cellular permeability. Selecting labeling density and linker length helps tune behavior.
• Caution: Free (unconjugated) NHS-ester dyes can react with biomolecule amines non-selectively; remove excess dye after labeling to reduce background in biological assays.

Buffer Applications

This item is a reactive fluorescent dye and not a buffering agent. It is not typically used to prepare buffer systems.
• Practical note (literature/general): For NHS-ester labeling, choose buffers without primary amines (avoid Tris, glycine). Commonly used:

• 50–100 mM sodium bicarbonate/carbonate, pH 8.3–8.6.
• 50–100 mM phosphate or HEPES, pH 7.5–8.2 (slower reaction but reduced hydrolysis).
  These are general guidelines and not product specifications.

Green Alternatives

• Solvent choice is the main sustainability lever for NHS-ester conjugations. While the dye identity is fixed, greener process options can reduce hazard and waste (literature/general).
• Comparison of common media:

• DMSO (preferred over DMF): Lower acute toxicity and better environmental profile than DMF; excellent solubilizer.
• Aqueous-organic blends: Minimize organic content by using concentrated dye stocks in DMSO, then immediate dilution into aqueous buffer for coupling; limit DMSO to ≤5% v/v when possible.
• Replace DMF with propylene carbonate or ethanol/water co-solvent in specific cases, provided solubility and kinetics remain acceptable; verify performance experimentally.
  • Process intensification:
• Use microscale reactions and high-efficiency mixing to reduce solvent volumes.
• Employ solid-phase or membrane-assisted labeling to simplify purification and reduce solvent usage.
  • Workup improvements:
• Prefer size-exclusion or spin-filtration over large-volume precipitation/extraction.
  • Tradeoffs: Greener co-solvents may reduce dye solubility or stability, potentially lowering DOL or requiring longer reaction times. Validate on small scale before process adoption.
  • Waste minimization: Prepare only the amount of dye stock needed immediately; NHS esters degrade upon storage in solution, generating waste if over-prepared.

Pharmaceutical Uses

No pharmacopeial status, excipient role, or formulation use is specified for this item; refer to CoA/Spec Sheet.
• General note: Fluorescein-type NHS-ester dyes are primarily research tools for labeling and assay development. They are not typically used as pharmaceutical excipients. Any use in regulated manufacturing would require independent qualification and validation.
• Compliance: For regulated applications, source lot-specific documentation (identity, purity, residual solvents, and impurity profiles) and assess against internal specifications.

Physical Properties

Item-specific physicochemical data are not listed in the Product Data. Do not treat literature values as product specifications.
• Molecular weight: Not specified for this item; refer to CoA/Spec Sheet.
• Molecular formula: Not specified for this item; refer to CoA/Spec Sheet.
• Appearance: Not specified for this item; refer to CoA/Spec Sheet.
• Melting point: Not specified for this item; refer to CoA/Spec Sheet.
• Boiling point: Not applicable for typical dye NHS esters (decompose before boiling in air; literature/general).
• Solubility (literature/general for fluorescein NHS esters):

• Readily soluble in anhydrous polar aprotic solvents (DMSO, DMF).
• Hydrolyzes in water or aqueous buffers over time (especially at pH >7); hence, stocks are typically prepared in dry solvent and used immediately upon dilution.
  • LogP, pKa, refractive index, density: Not specified for this item; refer to CoA/Spec Sheet.
  • Spectral properties (literature/general for fluorescein core):
• Absorption/emission typically in the green region; exact maxima depend on substituents, solvent, and pH. Do not use as product specifications; confirm experimentally for this SKU.
  • Stability notes (general): NHS esters are moisture sensitive and base-labile; protect from light and humidity. Store desiccated at low temperature as provided in Product Data.

Quality and Grades

• Grade/purity: Not specified for this item; refer to CoA/Spec Sheet.
• Interpreting grades (general guidance):

• Bioconjugation-grade NHS esters are typically supplied with low hydrolysis content and high purity to ensure efficient coupling and minimal background fluorescence.
• HPLC purity values, dye content, and counterion identity (if applicable) are commonly reported on the CoA; verify for this SKU.
  • Stabilizers: Not specified for this item; refer to CoA/Spec Sheet. Many NHS-ester dyes are supplied neat without stabilizers and require strictly dry handling (general).
  • Lot-specific documentation: Request CoA and Spec Sheet for this SKU (S1452259) for exact purity, identity testing method (e.g., HPLC/LC–MS), residual solvent limits, and spectral QC (absorbance/emission maxima, extinction coefficient), if available.
  • Practical note: Because NHS esters hydrolyze on storage/exposure to moisture, apparent purity can decrease after opening; record open date, minimize headspace humidity, and aliquot under dry conditions to preserve performance.

Reaction and Applications

• Core application (literature/general): NHS-ester activation enables selective acylation of primary aliphatic amines on biomolecules to form stable amide bonds. Typical targets include lysine side chains on proteins, N-termini of peptides, amino-modified oligonucleotides, and amine-functionalized surfaces/particles.
• Fluorescent labeling: The fluorescein-type SFX core yields green fluorescence suitable for microscopy, flow cytometry, in-gel imaging, and assay readouts. Choose buffers without primary amines and operate near pH 8.3–8.6 to balance amine nucleophilicity and NHS ester stability.
• Surface/particle modification: Label amine-bearing polymers (PEI, PAAm), silica with APTES, or beads with surface amines for calibration standards and biosensor development.
• Microarray and biosensor fabrication: Create fluorescently encoded probes and capture surfaces; co-control degree of labeling (DOL) by varying dye-to-target molar ratios and reaction time.
• Orthogonality (general): NHS ester is orthogonal to thiol-selective chemistries (maleimide) and azide–alkyne click reactions, allowing multi-color, multi-handle conjugates.
• Practical tips:

• Work quickly with freshly prepared dye stock; hydrolysis is the primary side reaction.
• Degas aqueous buffers to limit carbonate/bicarbonate CO2 shifts; keep ionic strength moderate.
• Purify conjugates by desalting columns, spin filters (10–30 kDa MWCO for proteins), or HPLC for small molecules/peptides.
  • Note: No manufacturer-specific applications were provided for this SKU; the above is general guidance for fluorescein-type NHS-ester dyes.

Reaction Conditions

General literature guidance for NHS-ester labeling; not product specifications. Optimize empirically for each target.
• Solvents and buffers:

• Prepare dye stocks at 5–20 mM in anhydrous DMSO or DMF.
• Use amine-free buffers (50–100 mM bicarbonate pH 8.3–8.6, or phosphate/HEPES pH 7.5–8.2). Avoid Tris/glycine.
  • Stoichiometry:
• Proteins: 2–10 mol dye per mol protein for mild labeling; up to 20 for higher DOL, balancing activity vs brightness.
• Peptides/oligos: 1.2–3.0 eq dye per amine site to limit over-labeling.
  • Temperature/time:
• 20–25°C for 15–60 min (proteins) or up to 2 h for less reactive substrates. Lower temperatures reduce hydrolysis but slow coupling.
  • Additives:
• 5–10% v/v DMSO in the reaction can aid solubility.
• Optional base scavengers are generally unnecessary; maintain pH with buffer.
  • Quench/purify:
• Quench unreacted NHS ester with ethanolamine (10–50 mM, pH ~8.5) after coupling, then remove excess dye by desalting, spin filtration, or HPLC (depending on substrate size).
  • Storage of solutions:
• Use immediately after preparation. If required, aliquot dye stock under dry inert gas, freeze at −20°C, protect from light; repeated thawing increases hydrolysis.
  • Analytical QC:
• Determine DOL for proteins by UV–Vis deconvolution using dye ε (from literature or CoA) and A280 correction; confirm conjugation by MS (peptides) or SDS‑PAGE/in‑gel fluorescence (proteins).

Safety and Handling

• GHS classification, signal word, hazard statements, and pictograms: Not specified for this item; refer to the SDS for authoritative safety information.
• General hazards for NHS-ester fluorophores (literature/general):

• May cause skin/eye irritation; avoid inhalation of dust or aerosols.
• NHS esters can react with biological amines; avoid contact with skin, eyes, and clothing.
  • Recommended PPE: Lab coat, safety glasses or goggles, appropriate chemical-resistant gloves (e.g., nitrile), and use in a fume hood or well-ventilated area.
  • Handling precautions:
• Minimize exposure to moisture; keep containers tightly closed under dry inert atmosphere when possible.
• Prepare solutions with anhydrous solvents; use desiccated tools and vials.
• Protect from light to avoid photodegradation and unintended photochemistry.
  • Incompatibilities (general): Strong bases (accelerate NHS hydrolysis), nucleophiles (amines, alcohols) outside intended coupling context, aqueous buffers at high pH, and prolonged exposure to humidity.
  • First-aid overview (general, not a substitute for SDS):
• Skin/eye contact: Rinse with water for at least 15 minutes; remove contaminated clothing; seek medical attention if irritation persists.
• Inhalation: Move to fresh air; seek medical attention if symptoms occur.
• Ingestion: Rinse mouth; do not induce vomiting; seek medical advice.
  • Waste: Collect dye-containing solutions and rinses as hazardous organic waste; follow institutional and local regulations.

Solvent Selection

This is a moisture-sensitive NHS-ester fluorophore; solvent choice dictates coupling efficiency and stability (literature/general).
• Primary stock solvents (general best practice):

• Anhydrous DMSO or anhydrous DMF for concentrated stock solutions (e.g., 5–20 mM).
• Dry acetonitrile can be used in some workflows, though solubility may be lower than in DMSO/DMF.
  • Aqueous compatibility:
• NHS esters hydrolyze in water; if aqueous dilution is required for conjugation, add the dye last into a vigorously stirred/quickly mixed buffered solution (pH 8.3–8.6) and use immediately (minutes to tens of minutes).
  • Buffer exclusions (general): Avoid primary amines (Tris, glycine), azide with copper catalysis, and high pH (>9) that accelerates hydrolysis. Use bicarbonate, phosphate, or HEPES buffers without amines.
  • Polarity class and miscibility (general):
• DMSO/DMF are polar aprotic, fully miscible with water; they facilitate rapid dissolution and subsequent dilution into aqueous buffer for labeling.
  • Comparison (general):
• DMSO vs DMF: DMSO is less volatile and often preferred for ease; DMF may provide higher solubility for some dyes but is more volatile and sensitive to water uptake.
  • Tip: Pre-dry solvents over molecular sieves (3Å/4Å) and confirm low water content by Karl Fischer where critical.

Storage and Reconstitution

• Storage conditions (per Product Data):

• Store at −20°C.
• Desiccated.
• Protect from light.
  • Shipping (per Product Data): Shipped in an ice chest with ice pads.
  • Reconstitution (general guidance for NHS-ester dyes; not a product specification):
• Equilibrate to room temperature in the dark before opening to avoid condensation.
• Dissolve in anhydrous DMSO or DMF to prepare a concentrated stock (e.g., 5–20 mM). Mix gently; avoid introducing moisture.
• Aliquot under dry inert atmosphere (e.g., nitrogen/argon), store tightly sealed at −20°C with desiccant.
  • Working solutions: Prepare immediately before use by diluting the anhydrous stock into amine-free buffer. Use promptly to minimize hydrolysis. Discard unused diluted solutions.
  • Freeze–thaw: Minimize cycles by aliquoting; NHS esters degrade with repeated thawing and moisture ingress.
  • Stability: Item-specific shelf life and purity retention are Not specified for this item; refer to CoA/Spec Sheet and SDS for detailed guidance.

Structure and Identity

• Item name indicates a mixed-isomer fluorescein-type N‑hydroxysuccinimide (NHS) ester: 5(6)-SFX, SE typically denotes a 5- and 6‑substituted isomer mixture of an SFX fluorophore bearing a succinimidyl ester reactive group. This enables amide bond formation with primary amines (literature/general).
• Exact structural identifiers for this catalog item are not provided.

• Molecular formula: Not specified for this item; refer to CoA/Spec Sheet.
• Molecular weight: Not specified for this item; refer to CoA/Spec Sheet.
• SMILES: Not specified for this item; refer to CoA/Spec Sheet.
• InChIKey: Not specified for this item; refer to CoA/Spec Sheet.
• CAS: 114616-31-8 (per Product Data).
  • Structural features (literature/general for fluorescein NHS esters):
• Xanthene fluorophore core with phenolic substituents; one carboxyl group activated as an NHS ester.
• The “5(6)” designation indicates positional isomers at the 5- or 6‑aromatic ring positions on the fluorescein scaffold.
• The “SE” (succinimidyl ester) is an activated carboxylate for nucleophilic acyl substitution by primary amines to form stable amide linkages.
  • 2D structure description (literature/general): Tricyclic xanthene ring system fused to a benzene ring (fluorescein-type), carrying phenolic OH groups and a carboxylate; one carboxyl is converted to an O‑succinimidyl ester; the imide ring (succinimide) is a five-membered ring with two carbonyls enhancing leaving-group ability.
  • Note: Because item-specific identifiers are absent, treat the above as general guidance for fluorescein NHS-ester dyes and confirm details from the CoA/Spec Sheet for this SKU (S1452259).

Synthetic Utility

• Functional group: N‑hydroxysuccinimide (NHS) ester of a fluorescein-type (SFX) carboxyl group. Acts as an activated acylating agent toward primary amines (literature/general).
• Reactivity:

• Rapid aminolysis to give amide bonds with release of N‑hydroxysuccinimide.
• Competing hydrolysis to regenerate the parent carboxylic acid; rate increases with pH and moisture.
  • Selectivity:
• Prefers aliphatic primary amines; secondary amines react more slowly; tertiary amines are generally unreactive under typical conditions.
• On proteins, lysine ε‑amines and N‑termini are primary sites; microenvironment pKa and accessibility affect labeling distribution.
  • Orthogonal strategies: Combine with thiol-selective handles (maleimide), azide/alkyne click partners, or hydrazide/aldehyde pairing to build multi-functional probes.
  • Applications in synthesis:
• Preparation of fluorescent probes and affinity tags.
• Construction of calibration standards and tracers for assay development.
• Immobilization on amine-functionalized solid supports to generate fluorescent resins and sensor interfaces.
  • Limitations: Moisture sensitivity necessitates anhydrous technique; base and nucleophile-rich media (e.g., amine buffers) suppress coupling efficiency. Control DOL to avoid self-quenching and loss of target activity (proteins/enzymes).

Target Specificity

No antigen/epitope, species reactivity, clone, or isotype information applies to this chemical reagent. This product is a small-molecule labeling dye and does not possess biological target specificity. No item-specific immunological data are provided.