9-cis-Astaxanthin , CAS No.113085-04-4

CAS: 113085-04-4 Cat. No.: C1430190 Formule: C₄₀H₅₂O₄ Poids moléculaire: 596.84

Storage

Store at -20°C

Shipped In

Ice chest + Ice pads

Vue d’ensemble

9-cis-Astaxanthin, an isomer of astaxanthin (3,3-dihydroxy-β,β-carotene-4,4-dione), is part of the xanthophyll family, which consists of oxygenated derivatives of carotenoids.

Specifications

Conditions de stockage de stockage

Store at -20°C

Expédié en

Ice chest + Ice pads

Ce produit nécessite l'expédition en chaîne froide. Les services terrestres et autres services économiques ne sont pas disponibles.

Noms et identifiants

Poids moléculaire

596.84

Application Protocols

Item-specific validated application protocols are not provided for this SKU; refer to CoA/Spec Sheet. The following general laboratory protocols are offered for reference (literature/best practice; adjust as needed):

• Preparation of concentrated stock solution:

  • In a darkened fume hood, weigh the required amount quickly into an amber vial. Add degassed, anhydrous solvent (e.g., DMSO, acetone, or ethanol) to prepare a 1–10 mM stock. Optionally add 0.01% BHT. Cap and purge headspace with N2/Ar. Store aliquots at ≤−20°C.

• Dilution into aqueous media:

  • Add stock dropwise to vigorously stirred buffer containing a carrier (e.g., 0.1% Tween 80, 0.1% BSA, cyclodextrin, or lipid micelles) to a final organic solvent content ≤1%. Work under minimal light.

• UV–Vis characterization:

  • Record spectra immediately after dissolution (e.g., in acetone or ethanol) using amber cuvettes. Expect strong bands around 470–500 nm; 9-cis typically shows slight hypsochromic shift and reduced fine structure vs all-trans.

• HPLC analysis (carotenoid-selective):

  • Column: C30, 250 × 4.6 mm, 3–5 µm. Mobile phase A: MeOH/H2O (95:5); B: MTBE. Gradient: 0–30 min, 95% A to 50% A. Flow: 1.0 mL/min; detection: 470–490 nm. Keep column and samples protected from light; use degassed solvents.

Note: These are general references; optimize for your specific setup and objectives.

Biological Roles

• General biochemical context (literature; not product claims):

  • Astaxanthin is a xanthophyll carotenoid produced by algae, yeast, and some plants; it accumulates in aquatic organisms via diet. The 9-cis isomer is one of several geometric isomers formed enzymatically or via photo/thermal isomerization.
  • Functions as a potent physical quencher of singlet oxygen and scavenger of reactive oxygen species in model systems. The conjugated polyene delocalizes unpaired electrons, and terminal hydroxyl/keto groups aid membrane anchoring.
  • In membranes, carotenoids modulate bilayer order and fluidity; the 9-cis configuration introduces a bend in the polyene that can alter orientation and distribution across leaflets compared to the all-trans isomer.
  • Binding/association: Carotenoids can associate with lipoproteins, lipid droplets, and carotenoid-binding proteins; isomer geometry can influence binding affinities and spectral properties of complexes (e.g., bathochromic/hypsochromic shifts).

• Experimental considerations:

  • Delivery into aqueous systems typically requires carriers (cyclodextrins, liposomes, protein complexes, or surfactants) to overcome water insolubility.
  • Distinguish isomer-specific effects, as 9-cis vs all-trans may differ in photostability, spectral features, membrane orientation, and reactivity in model assays.

Note: For research use only. No medical or clinical claims are made or implied.

Buffer Applications

This compound is a highly hydrophobic carotenoid and is not used as a buffering agent. It does not provide acid/base capacity in aqueous systems over a practical pH range.

• Practical note: To work with 9-cis-Astaxanthin in buffered systems, prepare concentrated stocks in DMSO or ethanol and dilute into buffer containing a suitable carrier (e.g., 0.1–1% lipid, serum albumin, cyclodextrin, or nonionic surfactant). Protect from light and minimize final organic cosolvent (<0.5–1%) to avoid precipitation.

For pH buffer system selection unrelated to this compound, consult standard buffering tables (e.g., phosphate, HEPES, Tris).

Green Alternatives

Green chemistry considerations for work involving 9-cis-Astaxanthin focus on solvent and energy choices, since the molecule itself is fixed.

• Preferred greener solvents (literature guidance):

  • Ethanol, isopropanol, ethyl acetate, and 2-methyltetrahydrofuran (2-MeTHF) can often replace chlorinated solvents for dissolution, extraction, and chromatography.
  • Supercritical CO2 (with ethanol as a co-solvent) is widely used for carotenoid extraction and could be considered for preparative work.

• Comparison (general; not item-specific):

  • Chlorinated (DCM, CHCl3): high solubility and stability but poor EHS profile.
  • Ethanol/EtOAc: lower toxicity and environmental impact; may require higher volumes or mild heating and rigorous deoxygenation to achieve comparable solubility.
  • 2-MeTHF: bio-based, good solvency for hydrophobes; ensure peroxide monitoring and stabilizers as needed.

• Practical green tips:

  • Use amber glassware and low-temperature processes to reduce energy input and degradation.
  • Degas greener solvents thoroughly (sparge with N2) and add minimal antioxidant to extend solution life.
  • For HPLC, adopt MeOH/ACN/MTBE systems with minimized MTBE fraction; consider ethanol where column compatibility allows.

• Trade-offs:

  • Greener solvents may increase risk of oxidative degradation due to higher oxygen solubility or slower dissolution; compensate with inerting and rapid handling.
  • Supercritical CO2 requires specialized equipment but reduces solvent waste and facilitates product recovery.

Pharmaceutical Uses

• Item-specific (Product Data): No pharmacopeial grade or excipient status is specified for this SKU; refer to CoA/Spec Sheet.

• General formulation context (literature; not product claims):

  • Carotenoids like astaxanthin are investigated as colorants/antioxidants in research formulations. The 9-cis isomer may be employed as a reference standard for analytical release testing and stability-indicating methods in development settings.
  • Formulation strategies emphasize protection from light and oxygen: lipid-based systems (oils, self-emulsifying drug delivery systems), microemulsions, cyclodextrin inclusion complexes, and polymeric micelles are common research approaches.
  • Excipients that can improve stability include tocopherols, ascorbyl palmitate, and BHT in trace amounts when compatible with the study design.

• Analytical controls:

  • Isomer ratio (9-cis vs others) and degradation profiling are critical quality attributes in development work. C30 HPLC with visible detection is typical; mass spectrometry supports identity.

Note: For research use only. No claims are made regarding therapeutic use, safety, or efficacy in humans or animals.

Physical Properties

• Item-specific (Product Data):

  • Appearance: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular weight: Not specified for this item; refer to CoA/Spec Sheet.

• Literature/general properties (for reference; not item specifications):

  • Physical state/color: deep red to reddish-purple solid, intensely colored due to the long conjugated polyene (literature, carotenoid class).
  • Melting behavior: carotenoids often soften and decompose before a sharp melt; reported astaxanthin shows decomposition on heating rather than a clean melting point (literature).
  • Boiling point: not applicable; decomposes before boiling at ambient pressure (literature).
  • Solubility: practically insoluble in water; soluble in nonpolar and moderately polar organic solvents (e.g., chloroform, dichloromethane, toluene, hexane, acetone, ethyl acetate). Limited solubility in alcohols; enhanced solubility in lipid/oils and in DMSO (literature).
  • LogP: large positive (strongly lipophilic) due to C40 backbone, tempered by two hydroxyls (literature, qualitative).
  • UV–Vis: strong absorption in visible region; typical λmax for astaxanthin in organic solvents ca. 470–500 nm with vibronic fine structure; cis-isomers often show slight hypsochromic shift and weaker fine structure compared to all-trans (literature).
  • Stability: highly sensitive to light, heat, and oxygen; undergoes oxidation and cis–trans isomerization. Stability enhanced under inert gas and with antioxidants (e.g., BHT) at low temperature (literature).
  • Refractive index, density, pKa: not commonly reported for solid carotenoids; no reliable single values (literature).

Quality and Grades

• Item-specific (Product Data):

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

• How to interpret quality for this material (general guidance for carotenoids; not item-specific):

  • Purity reporting: High-performance liquid chromatography (HPLC) at visible detection is standard, often specifying total purity and isomer distribution (all-trans vs specific cis isomers such as 9-cis). For isomer-sensitive studies, the percentage of 9-cis content and overall geometric purity are critical.
  • Impurities of concern: oxidative degradation products (epoxides, apocarotenoids), residual solvents, and other carotenoid isomers. Peroxide value and acid value are sometimes monitored for stability, but are not item specifications unless stated.
  • Stabilizers: Carotenoids are sometimes provided with micro-amounts of antioxidants (e.g., BHT) or in inerted packaging. Presence/absence and identity of any stabilizer must be confirmed on the CoA/spec sheet.
  • Optical characterization: λmax position and spectral fine structure (E1, E2, E3 bands) can indicate isomeric state and purity.
  • Recommended verification upon receipt (best practice):
    • Record UV–Vis spectrum in an appropriate solvent and compare to literature patterns for 9-cis vs all-trans.
    • Perform HPLC with a carotenoid-selective column (C30) to confirm isomeric profile.
    • Assess residual oxygen in container headspace and re-inert after opening.

Note: In the absence of a specified grade/purity for SKU C1430190, rely on the CoA for definitive specifications.

Reaction and Applications

This compound is generally used as a reference standard, probe molecule, and functional carotenoid, rather than as a routine reagent. Key application areas and relevant chemistry (literature/general):

• Analytical/standard uses:

  • Isomer-specific standard for HPLC/UPLC method development on C30 phases to distinguish 9-cis from all-trans and other cis astaxanthins.
  • Quantitation in studies of carotenoid isomerization, stability, and degradation under light/heat/oxygen.

• Photophysics and antioxidant chemistry:

  • Polyene enables strong visible absorption and efficient physical quenching of singlet oxygen and triplet sensitizer states; 9-cis isomer exhibits subtly different spectra and quenching efficiencies vs all-trans.
  • Radical scavenging proceeds via addition to the polyene or hydrogen atom transfer from the tertiary alcohols; follow-up by resonance-stabilized radical delocalization.

• Supramolecular/membrane studies:

  • 9-cis geometry alters molecular packing and orientation in lipid bilayers vs all-trans, affecting ordering and membrane rigidity—useful in biophysical assays (fluorescence anisotropy, DSC, EPR spin probes).

• Chemical manipulation (if derivatization is desired):

  • Hydroxyl protection as acetates or silyl ethers facilitates handling and reduces polarity for separations.
  • Reduction/oxidation at the 4-keto groups (e.g., to diols) or selective epoxidation of double bonds allows structure–activity exploration.

Practical tips: Work under inert gas in amberware; add trace antioxidant (e.g., 0.01% BHT) when compatible; minimize chromatographic exposure to light and oxygen; cool columns and use degassed eluents to limit on-column isomerization.

Reaction Conditions

Guidance below summarizes literature practices for carotenoid manipulation and 9-cis isomer handling; these are not item specifications.

• Cis–trans isomerization (enrichment of 9-cis):

  • Thermal: Dissolve astaxanthin in anhydrous toluene or chlorobenzene under N2, heat at 60–90°C in the dark for minutes to hours to reach photo/thermodynamic isomer equilibrium; monitor by C30 HPLC. Lower temperatures favor slower, more controllable isomerization.
  • Photochemical: Irradiate in the visible range using filtered light (e.g., >450 nm) at low temperature with oxygen excluded to bias specific cis isomers; quench and separate immediately to limit over-isomerization and oxidation.

• Hydroxyl protection (acetylation):

  • Reagents: Ac2O/pyridine or Ac2O/DMAP in DCM under N2, 0–25°C, 0.5–2 h. Work up rapidly, protect from light. Typical conversions high; purify on silica deactivated with 0.1% Et3N or use C18/C30 reverse phase.

• Ketone reduction:

  • Mild hydride sources (e.g., NaBH4/CeCl3 – Luche conditions) in MeOH or i-PrOH at 0–25°C can reduce 4-keto groups with minimized polyene attack. Strictly exclude oxygen and light.

• Epoxidation (selective):

  • m-CPBA or peracids at 0–5°C in DCM, short times, with careful stoichiometry; monitor by HPLC/UV–Vis for hypsochromic shifts indicating epoxide formation.

• Analytical conditions:

  • HPLC: C30 column, 30–40°C, gradient MeOH/MTBE/H2O (e.g., 80:18:2 to 50:48:2 over 30 min) at 1 mL/min, detection at 470–490 nm, resolves 9-cis from all-trans.

Always protect from light, use amber glassware, degassed solvents, and inert atmosphere.

Safety and Handling

• Item-specific (Product Data):

  • GHS classification, pictograms, signal word, H-statements: Not specified for this item; refer to SDS.
  • Storage conditions: Store at -20°C.
  • Shipped in: Ice chest + ice pads.

• General safety guidance for carotenoid xanthophylls (literature/best practice; defer to SDS for authoritative information):

  • Primary hazards: not strongly acutely toxic by typical laboratory exposure routes; may cause mechanical/chemical irritation to eyes, skin, and respiratory tract. Handle powders to avoid dust formation.
  • Sensitivity: photosensitive and oxygen-sensitive. Polyene backbone is readily oxidized; avoid exposure to light, elevated temperature, and air.
  • Incompatibilities: strong oxidizers, radical initiators, and halogens. Avoid peroxides and UV sources.
  • Recommended PPE: lab coat, safety glasses or face shield, and suitable chemically resistant gloves (e.g., nitrile). Use in a fume hood when weighing/dissolving. Consider amber glassware.
  • Handling tips:
    • Work rapidly under dim/amber light. Purge containers and headspace with nitrogen or argon after opening.
    • For solution work, include a trace antioxidant (e.g., 0.01% BHT) when compatible with downstream use.
    • Use dry, oxygen-free solvents. Avoid repeated freeze–thaw of solutions.
  • First-aid overview (general): in case of eye/skin contact, rinse with water for several minutes; remove contaminated clothing. If inhaled, move to fresh air. If ingested, rinse mouth. Seek medical advice as needed. Always consult the SDS specific to this item for detailed measures.

Solvent Selection

Solubility and solvent choice for 9-cis-Astaxanthin are governed by its long hydrophobic polyene and polar end-groups (diol-diketo xanthophyll).

• Polarity/miscibility (literature, general):

  • Water: essentially insoluble.
  • Miscible/soluble: chloroform, dichloromethane, tetrahydrofuran, acetone, ethyl acetate. Moderately soluble in alcohols (MeOH/EtOH/i-PrOH) and DMSO. Soluble in nonpolar hydrocarbons (hexane, toluene) and edible oils/fats.
  • Prefer low-oxygen, dry, and light-protected solvents to minimize oxidation and isomerization.

• Practical selection by use case:

  • Stock solutions for bioassays: DMSO or ethanol stocks (e.g., 1–10 mM) prepared under inert gas, then diluted into media with a carrier (BSA, surfactant, or lipid vehicle) to avoid precipitation. Protect from light.
  • Chromatography/HPLC: Reverse-phase C18 often works, but C30 phases give superior carotenoid resolution; mobile phases of MeOH/MTBE/H2O or MeOH/ACN with minor MTBE. For normal-phase TLC/flash, hexane/acetone or hexane/ethyl acetate mixtures are common.
  • Spectroscopy: Acetone, ethanol, or DCM give characteristic visible spectra with clear vibronic bands. Use amber cuvettes.

• Comparison notes (literature):

  • Chloroform/DCM: excellent solubility, but chlorinated; handle with care.
  • Acetone/EtOH: greener, convenient, but may offer slightly lower solubility and faster degradation if oxygenated.
  • Oils/liposomes: best for long-term stabilization in formulation studies, but complicate analytical quantification.

Storage and Reconstitution

• Item-specific (Product Data):

  • Storage Conditions: Store at -20°C.
  • Shipped In: Ice chest + ice pads.

• General best practices for this material class (literature; not item specifications):

  • Light/oxygen protection: Store in amber, airtight vials under inert gas (N2/Ar). Minimize headspace oxygen. Consider inclusion of a trace antioxidant (e.g., 0.01% BHT) if compatible.
  • Temperature: For short-term storage (days to weeks), 2–8°C under inert atmosphere can be acceptable; for long-term storage, −20°C or below is recommended. Avoid frost-free freezers with frequent warm cycles.
  • Solid handling: Allow vial to equilibrate to room temperature before opening to prevent moisture condensation. Work quickly in low light.

• Reconstitution guidance (for laboratory use):

  • Preferred solvents: degassed DMSO, ethanol, acetone, ethyl acetate, or chlorinated solvents (DCM/CHCl3) as needed. Typical stock concentrations: 1–10 mM.
  • Aqueous systems: Dilute organic stock into buffered media containing carriers (albumin, cyclodextrins, lipids, or nonionic surfactants) with vigorous mixing to prevent precipitation. Keep final organic content low (≤1%).
  • Aliquoting: Prepare single-use aliquots to avoid repeated freeze–thaw. Store solutions at ≤−20°C, protected from light, and use promptly after thawing.

• Disposal: Treat as organic chemical waste. Dispose of solutions and contaminated materials according to institutional and local regulations.

Always consult the item-specific CoA and SDS for definitive instructions.

Structure and Identity

Brief overview: 9-cis-Astaxanthin is a carotenoid xanthophyll (oxygenated carotenoid) and one cis-isomer of astaxanthin. It features a C40 polyene backbone with terminal ionone-type rings bearing 3-hydroxy-4-keto substitution.

• Item-specific (Product Data):

  • SKU: C1430190
  • CAS: 113085-04-4 (assigned to 9-cis isomer)
  • InChIKey: Not specified for this item; refer to CoA/Spec Sheet.
  • SMILES: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular formula: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular weight: Not specified for this item; refer to CoA/Spec Sheet.

• Literature/Computed identifiers and features (for general reference; not item specifications):

  • Typical molecular formula for astaxanthin isomers: C40H52O4 (literature).
  • Typical molecular weight: ~596.85 g/mol (literature, for C40H52O4).
  • Stereochemistry/isomerism: 9-cis refers to a cis double bond at C9–C10 along the polyene chain; additional E/Z geometry is present across multiple double bonds. Chiral centers at C3 and C3' may exist (R/S), and many preparations are mixtures of enantiomers unless specified.
  • Functional groups: conjugated polyene, two terminal β-ionone-type rings each bearing 3-hydroxyl and 4-keto substituents (dihydroxy-diketo xanthophyll).

• 2D structure description (general):

  • Central extended conjugated chain (~11 double bonds) connecting two substituted cyclohexene (ionone-like) rings. Each ring contains a ketone at the 4-position and a secondary alcohol at the 3-position. The 9-cis configuration introduces a single cis kink in the otherwise predominantly trans polyene backbone, influencing packing and spectral properties.

Synthetic Utility

Although 9-cis-Astaxanthin is typically a target molecule rather than a synthon, it can participate in or be derived through useful transformations (literature/general):

• Functional group handles:

  • Two secondary alcohols (3,3′-diol) allow for esterification (acetates, fatty esters) or silylation (TBS/TIPS) to modulate polarity and stability.
  • Two conjugated ketones (4,4′-diones) can undergo selective reduction to diols or further derivatization (e.g., oxime formation for analytical tagging).

• Polyene chemistry:

  • The extended conjugated chain undergoes E/Z isomerization thermally or photochemically; the 9-cis isomer can be enriched via controlled isomerization of all-trans precursors and chromatographic separation on C30 silica.
  • Electrophilic additions (e.g., halogenation, epoxidation) occur across double bonds; carefully controlled conditions can yield mono- or poly-epoxides—useful for structure–function studies.

• Protecting-group strategy:

  • Temporary protection of hydroxyls improves chromatographic handling and suppresses undesired hydrogen bonding or metal coordination during further manipulation.

• Conjugation/immobilization:

  • Coupling via carbonate/ester linkers to polymers, lipids, or surfaces creates stabilized conjugates for materials and sensor research.

Caveat: All synthetic operations should minimize light, oxygen, and heat exposure. Use dry, degassed solvents, amberware, and inert atmosphere to preserve the 9-cis configuration and prevent oxidative cleavage (apocarotenoid formation).

Target Specificity

Not applicable. This product is a small-molecule carotenoid and not a biological affinity reagent. No antigen/epitope, species reactivity, clone, or isotype is relevant.