Astaxanthin Powder: Properties, Uses & Lab Guide

Astaxanthin powder is a potent ketocarotenoid pigment widely used in biomedical, nutraceutical, and oxidative-stress research for its exceptional free-radical scavenging capacity.

Chemical Name

(3S,3′S)-3,3′-dihydroxy-β,β-carotene-4,4′-dione

CAS Number

472-61-7

Molecular Formula

C₄₀H₅₂O₄

Molecular Weight

596.84 g/mol

Appearance

Dark red to dark orange crystalline powder

Solubility

Soluble in DMSO, chloroform, and dichloromethane; poorly soluble in water

Storage Condition

Store at −20 °C, protected from light, under inert atmosphere

Chemical Identity and Physical Properties

Astaxanthin (CAS 472-61-7) is a xanthophyll carotenoid belonging to the broader class of tetraterpenoid pigments. Its IUPAC name is (3S,3′S)-3,3′-dihydroxy-β,β-carotene-4,4′-dione, and it has the molecular formula C₄₀H₅₂O₄ with a molecular weight of approximately 596.84 g/mol. The compound features a polyene backbone with conjugated double bonds flanked by two ionone rings, each bearing a hydroxyl group at the 3-position and a keto group at the 4-position. This unique bifunctional polar end-group arrangement is responsible for astaxanthin's superior antioxidant potency relative to other common carotenoids such as β-carotene or lutein.

As a powder, astaxanthin presents as dark red to dark orange crystals. It exists as three stereoisomers—(3S,3′S), (3R,3′R), and the meso (3R,3′S) form—which differ in biological activity and source of origin. Synthetic astaxanthin is predominantly a racemic mixture, while naturally derived material from Haematococcus pluvialis is enriched in the (3S,3′S) form.

Solubility, Formulation and Handling

Astaxanthin powder is lipophilic and therefore poorly soluble in aqueous systems. For in vitro research applications, it is most conveniently dissolved in dimethyl sulfoxide (DMSO), chloroform, or dichloromethane. When preparing stock solutions in DMSO, a concentration of 10–25 mM is typically achievable; researchers should verify solubility empirically for each new lot. The DMSO stock should subsequently be diluted into aqueous cell-culture media at a ratio that keeps the final DMSO concentration ≤0.1% (v/v) to minimise solvent cytotoxicity.

Because astaxanthin is highly susceptible to oxidative degradation and photoisomerisation, all handling should be performed under subdued or red-filtered light, and solutions should be prepared fresh or stored as small aliquots under argon or nitrogen at −20 °C. Amber vials or foil-wrapped tubes are recommended. Avoid repeated freeze-thaw cycles, which accelerate degradation and promote cis-isomer formation detectable by a shift in UV-Vis absorbance (λ_max ≈ 476 nm in ethanol).

Research Applications and Biological Activity

Astaxanthin powder is employed across a broad spectrum of research disciplines owing to its potent antioxidant, anti-inflammatory, and cytoprotective properties. In oxidative-stress models, it is used as a benchmark antioxidant to quench singlet oxygen and peroxyl radicals. Its unique molecular architecture allows it to span cell membranes, scavenging radicals at both the membrane interior and surface simultaneously—a mechanism not shared by purely lipophilic carotenoids.

Common research applications include: (1) Neuroprotection studies — astaxanthin crosses the blood-brain barrier and has been studied in models of ischemia-reperfusion injury and neurodegenerative disease; (2) Cardiovascular research — investigations into lipid peroxidation, LDL oxidation inhibition, and endothelial function; (3) Aquaculture and animal nutrition science — as a feed pigmentation and performance additive in salmonid and crustacean models; (4) Skin biology and photoprotection — UV-induced oxidative damage models in keratinocytes and fibroblasts; (5) Mitochondrial biology — studies on reactive oxygen species (ROS) modulation and mitochondrial membrane potential. Researchers should note that published in vitro effective concentrations vary widely depending on cell type and experimental model; pilot dose-response experiments are strongly recommended.

Stability, Quality and Analytical Characterisation

Astaxanthin is one of the more labile carotenoids due to the extended conjugated system and the presence of reactive carbonyl groups. Key degradation pathways include thermal oxidation, photo-oxidation, and acid/base-catalysed isomerisation. Researchers should assess powder purity by high-performance liquid chromatography (HPLC) with UV-Vis detection at 476 nm, which also resolves the three geometric isomers (all-E, 9Z, 13Z). Nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (LC-MS/MS) are employed for structural confirmation.

For procurement and QC purposes, key certificate-of-analysis (CoA) parameters to request include: purity (% by HPLC), water content (Karl Fischer titration), heavy metal limits, and microbiological specifications where relevant. Aladdin Scientific's GMP1529217 should be accompanied by a CoA; contact technical support to obtain batch-specific documentation. Proper cold-chain shipping (≤−20 °C or on dry ice) is essential to maintain specification upon receipt.

Safety, Regulatory and Handling Precautions

Astaxanthin powder is generally regarded as having low acute toxicity and is approved as a food colour and dietary supplement ingredient in multiple jurisdictions. However, for laboratory use, standard chemical handling precautions apply. Avoid inhalation of fine powder; use a dust mask or work in a fume hood when weighing. Avoid contact with eyes and skin. Consult the Safety Data Sheet (SDS) supplied with GMP1529217 for full hazard classification, first-aid measures, and disposal guidance.

From a regulatory standpoint, the grade and specifications of astaxanthin required may differ between research use and any downstream formulation or clinical application. Aladdin Scientific's GMP1529217 is intended for research use only and must not be used in humans or animals without appropriate regulatory approval. Researchers working under GLP or GMP frameworks should verify that the product certificate meets their quality-system requirements before use.

Frequently asked questions

What solvents can I use to dissolve astaxanthin powder for cell-culture experiments?

Astaxanthin is best dissolved in DMSO for cell-culture use, typically at a stock concentration of 10–25 mM. Dilute into culture medium immediately before use and ensure the final DMSO concentration does not exceed 0.1% (v/v) to avoid solvent cytotoxicity. Ethanol is an alternative carrier but may require a lower stock concentration.

How should astaxanthin powder (GMP1529217) be stored to prevent degradation?

Store astaxanthin powder at −20 °C in a tightly sealed container, protected from light and moisture, under an inert atmosphere (nitrogen or argon). Upon opening, re-seal immediately and return to the freezer. Avoid repeated freeze-thaw cycles, as these promote oxidative degradation and geometric isomerisation.

What is the difference between synthetic and natural-source astaxanthin powder?

Synthetic astaxanthin is predominantly a racemic mixture of (3R,3′R) and (3S,3′S) stereoisomers along with the meso form, while natural astaxanthin from Haematococcus pluvialis is enriched in the (3S,3′S) enantiomer. The stereoisomers differ in their biological activity, esterification state, and bioavailability. Researchers should specify the isomeric composition required when selecting a product for biological studies.

How can I confirm the purity and identity of astaxanthin powder before use?

Purity is best assessed by HPLC with UV-Vis detection at 476 nm, which can resolve individual geometric isomers. Identity can be confirmed by UV-Vis spectroscopy (λmax ≈ 476 nm in ethanol) and by mass spectrometry (expected [M+H]⁺ ≈ 597.4 for C₄₀H₅₂O₄). Request a batch-specific Certificate of Analysis from Aladdin Scientific to verify that the lot meets specification before initiating experiments.

Is GMP1529217 suitable for in vivo animal studies?

GMP1529217 is designated for research use only. Researchers intending to use it in animal studies must ensure compliance with institutional animal ethics committee requirements and relevant regulations. Verify that the grade and purity specifications on the CoA are appropriate for your specific experimental design before proceeding.

References

1. Guerin M, Huntley ME, Olaizola M. Haematococcus astaxanthin: applications for human health and nutrition. Trends Biotechnol. 2003;21(5):210-216. doi:10.1016/S0167-7799(03)00078-7
2. Nishida Y, Yamashita E, Miki W. Quenching activities of common hydrophilic and lipophilic antioxidants against singlet oxygen using chemiluminescence detection system. Carotenoid Sci. 2007;11:16-20.
3. Ambati RR, Phang SM, Ravi S, Aswathanarayana RG. Astaxanthin: sources, extraction, stability, biological activities and its commercial applications — a review. Mar Drugs. 2014;12(1):128-152. doi:10.3390/md12010128

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.