Dimethyldioctadecylammonium bromide

Synonym(s):Dimethyldioctadecylammonium (Bromide Salt);Distearyldimethylammonium bromide

CAS NO.：3700-67-2
Empirical Formula: C38H80BrN
Molecular Weight: 630.95
MDL number: MFCD00041975
EINECS: 223-037-6
SAFETY DATA SHEET (SDS)
Update Date: 2026-04-24 12:01:10

Dimethyldioctadecylammonium bromide Structural

What is Dimethyldioctadecylammonium bromide?

Description

18:0 DDAB is a double-chained quaternary ammonium surfactant with a bromide counter ion.

Chemical properties

white powder

The Uses of Dimethyldioctadecylammonium bromide

Dimethyldioctadecylammonium bromide has been used in a study to assess the interaction of its monolayers with DNA using specular neutron reflection, surface pressure-area isotherms, and Brewster angle microscopy. It has also been used in a study to investigate new adjuvants for use in kill vaccines for bovine viral diarrhea virus (BVDV).

General Description

18:0 DDAB is cationic lipid and a quaternary ammonium salt. The hydrocarbon tails are saturated unlike the ionizable lipids.

Biochem/physiol Actions

18:0 DDAB is a surface-active molecule, used as an adjuvant to induce systemic immune response. It is non-toxic.

Purification Methods

Crystallise the bromide from acetone, then MeOH [Lukac J Am Chem Soc 106 4387 1984]. Also purify it by chromatography on alumina by washing with *C6H6 and eluting with Me2CO, evaporating and crystallising from MeCN [Swain & Kreevoy J Am Chem Soc 77 1126 1955]. [Beilstein 4 IV 829.]

Properties of Dimethyldioctadecylammonium bromide

Melting point:	~160 °C
Density	1.047
RTECS	RG0185984
refractive index	1.5260 (estimate)
storage temp.	-20°C
solubility	Chloroform (Slightly), Ethyl Acetate (Slightly, Heated), Hexanes (Slightly, Heat
form	Granular Powder
color	White
BRN	3580323
Stability:	Stable. Incompatible with strong oxidizing agents.
CAS DataBase Reference	3700-67-2(CAS DataBase Reference)
EPA Substance Registry System	1-Octadecanaminium, N,N-dimethyl-N-octadecyl-, bromide (3700-67-2)

Safety information for Dimethyldioctadecylammonium bromide

Signal word	Danger
Pictogram(s)	Skull and Crossbones Acute Toxicity GHS06 Health Hazard GHS08
GHS Hazard Statements	H302:Acute toxicity,oral H315:Skin corrosion/irritation H319:Serious eye damage/eye irritation H331:Acute toxicity,inhalation H336:Specific target organ toxicity,single exposure; Narcotic effects H351:Carcinogenicity H372:Specific target organ toxicity, repeated exposure H412:Hazardous to the aquatic environment, long-term hazard
Precautionary Statement Codes	P201:Obtain special instructions before use. P273:Avoid release to the environment. P302+P352:IF ON SKIN: wash with plenty of soap and water. P308+P313:IF exposed or concerned: Get medical advice/attention.