3,3'-Dithiobis(6-nitrobenzoic acid)

  • 2,2'-Dinitro-5,5'-dithiodibenzoic acid
  • Ellman’s reagent
  • DTNB
Formula
C14H8N2O8S2
Structure
Description
Yellow solid.

Registry Numbers and Inventories.
CAS
69-78-3
EC (EINECS/ELINCS)
200-714-4
R 36/37/38
RTECS
DG9650000
RTECS class
Other
Beilstein/Gmelin
1896821
Beilstein Reference
4-10-00-00344
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Korea ECL
Listed

Properties.
Formula
C14H8N2O8S2
Formula mass
396.36
Melting point, °C
240 - 244
Vapor density (air=1)
13.7
Solubility in water
Soluble
pKa/pKb
1.57 (pKa)

Hazards and Protection.
Storage
Store in a cool, dry place. Keep container closed when not in use. Keep containers tightly closed.
Handling
Wash thoroughly after handling. Wash hands before eating. Remove contaminated clothing and wash before reuse. Use with adequate ventilation. Avoid contact with eyes, skin, and clothing. Avoid ingestion and inhalation.
Protection
Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to prevent skin exposure.
Respirators
Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.
Small spills/leaks
Vacuum or sweep up material and place into a suitable disposal container. Reduce airborne dust and prevent scattering by moistening with water. Clean up spills immediately, using the appropriate protective equipment. Avoid generating dusty conditions. Provide ventilation.
Disposal code
4
Stability
Stable under normal temperatures and pressures.
Incompatibilities
Strong oxidizing agents.
Decomposition
Nitrogen oxides, carbon monoxide, oxides of nitrogen, oxides of sulfur, irritating and toxic fumes and gases, carbon dioxide, nitrogen.

Fire.
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. To extinguish fire, use water, dry chemical, chemical foam, or alcohol-resistant foam.

Health.
Exposure effects
   Ingestion
May cause gastrointestinal irritation with nausea, vomiting and diarrhea. The toxicological properties of this substance have not been fully investigated.
   Inhalation
May cause respiratory tract irritation. The toxicological properties of this substance have not been fully investigated.
   Skin
May cause skin irritation.
   Eyes
May cause eye irritation.

First aid
 
   Ingestion
If victim is conscious and alert, give 2-4 cupfuls of milk or water. Never give anything by mouth to an unconscious person. Get medical aid.
   Inhalation
Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid.
   Skin
Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Get medical aid if irritation develops or persists. Wash clothing before reuse.
   Eyes
Immediately flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid immediately.

Transport.
HS Code
2930 90 70