Monomethyl phthalate is a phthalate metabolite. Monomethyl phthalate serves as a urinary biomarker for the detection of thyroid cancer and benign nodules following phthalate exposure.

Physicochemical Properties

Molecular Formula	C9H8O4
Molecular Weight	180.16
Exact Mass	180.042
CAS #	4376-18-5
Related CAS #	Monomethyl phthalate-d4;1276197-40-0
PubChem CID	20392
Appearance	White to off-white solid powder
Density	1.3±0.1 g/cm3
Boiling Point	328.9±25.0 °C at 760 mmHg
Melting Point	82-84 °C(lit.)
Flash Point	134.7±16.7 °C
Vapour Pressure	0.0±0.8 mmHg at 25°C
Index of Refraction	1.556
LogP	1.13
Hydrogen Bond Donor Count	1
Hydrogen Bond Acceptor Count	4
Rotatable Bond Count	3
Heavy Atom Count	13
Complexity	212
Defined Atom Stereocenter Count	0
InChi Key	FNJSWIPFHMKRAT-UHFFFAOYSA-N
InChi Code	InChI=1S/C9H8O4/c1-13-9(12)7-5-3-2-4-6(7)8(10)11/h2-5H,1H3,(H,10,11)
Chemical Name	2-methoxycarbonylbenzoic acid
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

References	[1]. Urinary biomarkers of phthalates exposure and risks of thyroid cancer and benign nodule. J Hazard Mater. 2020 Feb 5;383:121189.
Additional Infomation	Monomethyl phthalate is a methyl ester and a phthalic acid monoester. Monomethyl phthalate is a metabolite, or breakdown product, of dimethyl phthalate, used in insect repellant, plastic, and as a rocket propellant.

Solubility Data

Solubility (In Vitro)

DMSO: ≥ 100 mg/mL (555.06 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.5 mg/mL (13.88 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 25.0 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: ≥ 2.5 mg/mL (13.88 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 25.0 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: ≥ 2.5 mg/mL (13.88 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 25.0 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	5.5506 mL	27.7531 mL	55.5062 mL
	5 mM	1.1101 mL	5.5506 mL	11.1012 mL
	10 mM	0.5551 mL	2.7753 mL	5.5506 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.