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CAS 616-91-1 N-Acetyl-L-cysteine
Overview
N-Acetyl-L-cysteine (NAC; Acetylcysteine; CAS 616-91-1; C₅H₉NO₃S, 163.19 g/mol) is a high-purity, fermentation-derived thiol antioxidant/reducing agent and glutathione precursor used across pharmaceuticals & nutraceuticals (tablets/capsules, solutions), inhalation/oral liquid formulations, food & beverage fortification where permitted, and cosmetics/personal care as an anti-oxidation/chelating aid
Product Description
616-91-1 N-Acetyl-L-cysteine
Formulation notes: prepare aqueous solutions with controlled pH (typically mildly acidic), limit exposure to air/light/heat to minimize oxidation to disulfides; use suitable antioxidants/chelators as needed. Available in USP/EP/JP and food/cosmetic grades with low moisture and tight impurity controls. Store tightly closed, cool and dry, protected from light. COA/TDS/SDS available; lab-to-bulk packaging on request.
N-Acetyl-L-cysteine (NAC) — Product Specification
CAS: 616-91-1 | Formula: C5H9NO3S | Molecular weight: 163.19 g/mol | Grade options: USP / EP / JP · food/cosmetic grades
Identity & Form
| Appearance | White to off-white crystalline powder; mild sulfur odor |
|---|---|
| Solubility | Freely soluble in water (acidic); sparingly soluble in ethanol; practically insoluble in non-polar solvents |
| Function | Thiol antioxidant/reducing agent; mucolytic; glutathione precursor |
| Documents | COA · TDS · SDS · Allergen/Non-GMO statements |
Typical Specification — Pharma / Nutra Grade (example)
| Assay (HPLC, dried basis) | 98.5 – 101.5% (w/w) |
|---|---|
| Identification | IR spectrum conforms; HPLC retention time conforms |
| Specific rotation [α]D20 | +21° to +27° (c = 1, 1 M HCl) |
| pH (1% aq., 25 °C) | 2.0 – 2.8 |
| Melting range | 108 – 110 °C |
| Water (Karl Fischer) | ≤ 0.50% (w/w) |
| Residue on ignition / Sulfated ash | ≤ 0.10% |
| Related substances (HPLC) | Individual impurity ≤ 0.2%; total ≤ 0.5% |
| Heavy metals | Pb ≤ 2 ppm · As ≤ 1 ppm · Cd ≤ 1 ppm · Hg ≤ 0.1 ppm |
| Microbial limits | TAMC ≤ 1.0 × 103 cfu/g · TYMC ≤ 1.0 × 102 cfu/g · E. coli/Salmonella: absent |
| Appearance (QC) | Free-flowing; no visible foreign matter |
Optional Controls — Low-Oxidation / Process-Oriented
| Disulfide content (as DAC/DAC2) | ≤ 0.10% (w/w) (tighter limits on request) |
|---|---|
| Endotoxin (LAL) | ≤ 5.0 EU/g (lower on request) |
| Residual solvents | Meets ICH Q3C |
| Particle size | DC grade available (e.g., D90 150–400 μm) |
Applications & Handling
| Main uses | Tablets/capsules, oral liquids, inhalation solutions, food/beverage fortification (where permitted), cosmetics/personal care |
|---|---|
| Handling | Prepare aqueous solutions at controlled pH (mildly acidic); limit air/light/heat exposure to minimize oxidation to disulfides; use suitable antioxidants/chelators as needed |
| Storage | Store tightly closed, cool and dry; protect from light |
Packaging & Logistics
| Packaging | 1–5 kg alu-foil bags (inner PE) · 25 kg fiber drum; custom packs on request |
|---|---|
| Compliance | USP / EP / JP where applicable; Halal/Kosher upon request |
| Ports | Qingdao · Shanghai · Tianjin |
| To quote (please specify) | Target grade (USP/EP/JP/food/cosmetic), impurity/endotoxin limits, particle size/DC, pack size, destination, and required documents |
© Shandong Yinglang Chemical CO.,LTD · Information for B2B technical marketing only.
PACKING AND DELIVERY
Packing and delivery
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