A9165 Sigma-Aldrich


BioReagent, suitable for cell culture

Synonym: LNAC, NAC

  • CAS Number 616-91-1

  • Linear Formula HSCH2CH(NHCOCH3)CO2H

  • Molecular Weight 163.19

  •  Beilstein/REAXYS Number 1724426

  •  EC Number 210-498-3

  •  MDL number MFCD00004880

  •  PubChem Substance ID 24891402

  •  NACRES NA.26



Related Categories Amino Acids, Amino Acids & Vitamins, Amino Acids and Vitamins, Amino acids, Application Index,
Quality Level   200
product line   BioReagent
assay   ≥99% (TLC)
form   powder
application(s)   cell culture | mammalian: suitable
color   white to off-white
mp   106-108 °C (lit.)
solubility   H2O: 100 mg/mL (with heating)
storage temp.   2-8°C
SMILES string   CC(=O)N[C@@H](CS)C(O)=O
InChI   1S/C5H9NO3S/c1-3(7)6-4(2-10)5(8)9/h4,10H,2H2,1H3,(H,6,7)(H,8,9)/t4-/m0/s1



N-Acetyl-L-cysteine has been used as a component of intestinal basal medium for the culture of mouse intestinal stem cells and also as a component of expansion medium.


5, 25, 100 g in poly bottle

Biochem/physiol Actions

Antioxidant and mucolytic agent. Increases cellular pools of free radical scavengers. Reported to prevent apoptosis in neuronal cells but induce apoptosis in smooth muscle cells. Inhibits HIV replication. May serve as a substrate for microsomal glutathione transferase.

Safety & Documentation

Safety Information

Personal Protective Equipment 
NONH for all modes of transport
WGK Germany 
Flash Point(F) 
Not applicable
Flash Point(C) 
Not applicable


Certificate of Analysis (COA)

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Certificate of Origin (COO)

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Frequently Asked Questions

Which document(s) contains shelf-life or expiration date information for a given product?
If available for a given product, the recommended re-test date or the expiration date can be found on the Certificate of Analysis.
How do I get lot-specific information or a Certificate of Analysis?
The lot specific COA document can be found by entering the lot number above under the "Documents" section.
My media turned yellow when I added N-acetyl cysteine (NAC), Product A9165.Why?
The pH of a 1% solution is 2.0-2.8.You may need to adjust the pH of the media with NaOH.Or, prior to addition to the media, you can initially dilute the NAC with PBS, and then add it to the culture media.
How stable is a solution of Product A9165, N-acetyl cysteine (NAC)?
Aqueous solutions of cysteine oxidize to cystine on contact with air at neutral or alkaline pH. We recommend making aqueous solutions fresh.NAC is relatively stable in acid.Solutions in acid are stable and can be stored at -20 °C.
What concentration of Product A9165, N-Acetyl-L-cysteine (NAC), should I use for cell culture?
Cell culture testing is performed at 0.82 g/L.The exact concentration will depend upon your application.
What is the half life ofProduct A9165, N-Acetyl-L-cysteine (NAC), in cell culture?
We have not tested the half-life of NAC solutions in our labs here at Sigma. However, this subject has been reviewed in Neuropsychopharmacology, 29, 2018-2023 (2004).
How do I find price and availability?
There are several ways to find pricing and availability for our products. Once you log onto our website, you will find the price and availability displayed on the product detail page. You can contact any of our Customer Sales and Service offices to receive a quote. USA customers: 1-800-325-3010 or view local office numbers.
What is the Department of Transportation shipping information for this product?
Transportation information can be found in Section 14 of the product's (M)SDS.To access the shipping information for this material, use the link on the product detail page for the product.
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