Estradiol-d4 is the deuterium labelled form of Estradiol. Estradiol is a steroid sex hormone that is essential for maintaining female fertility and secondary sexual characteristics. Estradiol upregulates IL-6 expression through the estrogen receptor beta (ERβ) pathway.

Physicochemical Properties

Molecular Formula	C18H20D4O2
Molecular Weight	276.41
Exact Mass	276.203
CAS #	66789-03-5
Related CAS #	Estradiol;50-28-2;Estradiol-d3;79037-37-9;Estradiol-d5;221093-45-4;rel-Estradiol-13C6
PubChem CID	87229045
Appearance	White to off-white solid powder
LogP	3.609
Hydrogen Bond Donor Count	2
Hydrogen Bond Acceptor Count	2
Rotatable Bond Count	0
Heavy Atom Count	20
Complexity	382
Defined Atom Stereocenter Count	5
SMILES	[2H]C1=CC2=C(CC[C@@H]3[C@@H]2CC[C@]4([C@H]3CC([C@@H]4O)([2H])[2H])C)C(=C1O)[2H]
InChi Key	VOXZDWNPVJITMN-GKCQEISNSA-N
InChi Code	InChI=1S/C18H24O2/c1-18-9-8-14-13-5-3-12(19)10-11(13)2-4-15(14)16(18)6-7-17(18)20/h3,5,10,14-17,19-20H,2,4,6-9H2,1H3/t14-,15-,16+,17+,18+/m1/s1/i3D,7D2,10D
Chemical Name	(8R,9S,13S,14S,17S)-2,4,16,16-tetradeuterio-13-methyl-7,8,9,11,12,14,15,17-octahydro-6H-cyclopenta[a]phenanthrene-3,17-diol
HS Tariff Code	2934.99.9001
Storage	Powder-20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month
Shipping Condition	Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Biological Activity

ln Vitro	Drug compounds have included stable heavy isotopes of carbon, hydrogen, and other elements, mostly as quantitative tracers while the drugs were being developed. Because deuteration may have an effect on a drug's pharmacokinetics and metabolic properties, it is a cause for concern [1].
References	[1]. Impact of Deuterium Substitution on the Pharmacokinetics of Pharmaceuticals. Ann Pharmacother. 2019;53(2):211-216. [2]. Estradiol increases the sensitivity of hippocampal CA1 pyramidal cells to NMDA receptor-mediated synaptic input: correlation with dendritic spine density. J Neurosci. 1997 Mar 1;17(5):1848-59.

Solubility Data

Solubility (In Vitro)

DMSO: 250 mg/mL (904.45 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.08 mg/mL (7.53 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL. Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution. Solubility in Formulation 2: ≥ 2.08 mg/mL (7.53 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly. Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution. Solubility in Formulation 3: ≥ 2.08 mg/mL (7.53 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	3.6178 mL	18.0891 mL	36.1781 mL
	5 mM	0.7236 mL	3.6178 mL	7.2356 mL
	10 mM	0.3618 mL	1.8089 mL	3.6178 mL

*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.