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Molekula

Molekula

L-Tryptophan

SKU 13831082 CAS 73-22-3 C11H12N2O2 MW 204.23 In stock (5+ packs) — same-day dispatch Bulk quantities on request

Supplying 4,500+ customers in over 80 countries

ISO 9001:2015 & ISO 14001:2015 certified · Supplying laboratories and industry since 2000 · Listed pack sizes are a starting point — we manufacture, source and repack to the quantity you need

L-Tryptophan is an essential amino acid used in nutritional supplements, pharmaceuticals, and research. It serves as a precursor to serotonin and melatonin, supporting mood and sleep regulation. Available in powder form, it has a CAS number of 73-22-3, molecular formula C11H12N2O2, and a molecular weight of 204.23 g/mol. Stable at ambient storage conditions. Molekula supplies L-Tryptophan from research to bulk quantities with full documentation and ISO 9001:2015 traceability.

Expect a response within hours Speak to a chemist: +44 (0) 3302 000333

Example image for illustration only. Other packaging and pack sizes are available.

Pricing & pack sizes

Pack sizes & pricing

These pack sizes aren't a limit. Molekula manufactures, sources and repacks to order — if you need 500 kg and only see 1 kg listed, . We quote from grams to multi-tonne.

Need a different size? Add the nearest pack and change the size in your basket — we price it at the same rate per unit.

  • 100 g — $161.50 per pack
  • 500 g — $370.50 per pack
  • 1 kg — $532.00 per pack

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Tell us how much you need and when — drums, IBCs, sacks or a one-off bulk lot. We'll manufacture or source it and come back with a price.

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Prices exclude VAT/sales tax and shipping.

Specifications

Property Value
Appearance White Powder
Specific rotation -29.4 to -32.8
Identification Conforms to reference
pH 5.5 to 7.0
Loss on Drying ≤ 0.3%
Specification Conforms to USP specification
Chloride (Cl-) ≤ 0.05%
Assay ≥ 98.5%
Residue on Ignition ≤ 0.1%
Iron (Fe) ≤ 0.003%
Lead (Pb) ≤ 0.0015%

Storage & handling

Property Value
Storage Temperature Ambient
Acidity Neutral

Literature values

Published physical properties of the substance, not batch specifications.

Property Value
Odour Odorless
Melting Point 282 °C (decomposes)
Solubility (other solvents) Slightly soluble in acetic acid, ethanol; insoluble in ethyl ether
pKa pKa = 7.38 (at 25 °C)
log P (octanol/water) -1.06

Source: PubChem CID 6305 (HSDB, DrugBank)

Identification

Property Value
SKU 13831082
CAS Number 73-22-3
IUPAC Name (2S)-2-amino-3-(1H-indol-3-yl)propanoic acid
EC Number 200-795-6
Molecular Formula C11H12N2O2
Molecular Weight 204.23
Exact Mass 204.0899
SMILES C1=CC=C2C(=C1)C(=CN2)C[C@@H](C(=O)O)N
InChIKey QIVBCDIJIAJPQS-VIFPVBQESA-N
InChI InChI=1S/C11H12N2O2/c12-9(11(14)15)5-7-6-13-10-4-2-1-3-8(7)10/h1-4,6,9,13H,5,12H2,(H,14,15)/t9-/m0/s1
PubChem CID 6305
REACH Code Y113
TSCA Listed Yes
HTS Code 29339975
Tariff Code 2933998090

Safety & GHS

Precautionary statements

  • P264 Wash thoroughly after handling
  • P280 Wear protective gloves/protective clothing/eye protection/face protection
  • P308+313 IF exposed or concerned: Get medical advice/attention

Documents

Certificate of Analysis (CoA) by batch

Enter a lot or batch number to retrieve the CoA for that specific batch. We can generate one from spec data if no PDF is on file.

Synonyms

  • (2S)-2-amino-3-(1H-indol-3-yl)propanoic acid
  • (S)-Tryptophan
  • Ardeytropin
  • Indole-3-alanine
  • L-Tryptophane
  • Pacitron
  • trofan
  • tryptacin
  • tryptophan
  • Tryptophane

Frequently asked questions

What is L-Tryptophan used for?

L-Tryptophan is primarily used as a dietary supplement and in the synthesis of serotonin and melatonin, supporting mood regulation and sleep cycles.

What is the chemical formula and molecular weight of L-Tryptophan?

The formula is C11H12N2O2 with a molecular weight of 204.23 g/mol.

How should L-Tryptophan be stored?

Store at ambient temperature, protected from moisture and light.

What grade of L-Tryptophan does Molekula supply?

Molekula supplies L-Tryptophan in pharmaceutical and research grade.

Can Molekula supply L-Tryptophan in bulk?

Yes, Molekula can supply L-Tryptophan in bulk quantities; please contact sales for details.

What documentation comes with an order of L-Tryptophan?

Each order includes a Certificate of Analysis (CoA) and Safety Data Sheet (SDS).

Ready to order or need a custom pack?

Tell us the product, grade, and quantity — Molekula usually responds within one working day with pricing and lead time.

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