Sodium oleate is a chemical compound, an unsaturated fatty acid and the sodium salt of oleic acid.

The name describes the structure of the molecule:

• Sodium indicates the presence of sodium ions in the molecule.
• Oleate, derived from the word "oleic." It indicates that the molecule is a salt or ester of oleic acid, a monounsaturated fatty acid.

Description of the raw materials used in its production:

• Oleic Acid - Oleic acid is a monounsaturated fatty acid naturally found in various vegetable oils, such as olive oil and sunflower oil. It is extracted from these sources or chemically synthesized. Oleic acid is the main component of sodium oleate.
• Sodium - Sodium is a chemical element found in many compounds. In the production of sodium oleate, oleic acid reacts with sodium hydroxide (NaOH) to form sodium oleate. This chemical reaction involves the replacement of the hydroxyl group of oleic acid with a sodium atom.

Industrial chemical synthesis step-by-step:

• Saponification - Oleic acid is reacted with sodium hydroxide in a saponification reaction. During this reaction, the carboxylic acid group of oleic acid reacts with sodium hydroxide, forming sodium oleate and water. This reaction results in the formation of a sodium salt of oleic acid.
• Purification - The crude product obtained from the saponification reaction is purified to remove any impurities or by-products. This can be done through processes such as filtration, crystallization, or centrifugation.
• Drying - The purified sodium oleate is dried to remove residual moisture and obtain a powder or dry solid.
• Quality Control - The dried sodium oleate undergoes quality control checks to ensure its purity, stability, and compliance with industry standards.

It occurs as a white or yellowish powder that is soluble in water and ethyl alcohol; insoluble in benzene.

What it is used for and where

Medical

Sodium oleate can induce disturbances of lipid metabolism and lipid deposition in HepG2 cells (1). It is also considered to be an effective new therapy to improve antibiotic deficiency treatment towards biofilm resistance (2) and an improver of chrysin oral absorption (3).

Pure sodium oleate is used for the activation of protein kinase C in liver cells.

Cosmetics

Viscosity-stable anionic surfactant in the production of soaps, creams and personal care products as it improves the performance of polymer systems with regard to viscosity and other rheological properties.

Cleansing agent. Ingredient that cleanses skin without exploiting the surface-active properties that produce a lowering of the surface tension of the stratum corneum. 

Surfactant - Emulsifying agent. Emulsions are thermodynamically unstable and are used to soothe or soften the skin and emulsify, so they need a specific, stabilising ingredient. This ingredient forms a film, lowers the surface tension and makes two immiscible liquids miscible. A very important factor affecting the stability of the emulsion is the amount of the emulsifying agent. Emulsifiers have the property of reducing the oil/water or water/oil interfacial tension, improving the stability of the emulsion and also directly influencing the stability, sensory properties and surface tension of sunscreens by modulating the filmometric performance.

Surfactant - Cleansing agent. Cosmetic products used to cleanse the skin utilise the surface-active action that produces a lowering of the surface tension of the stratum corneum, facilitating the removal of dirt and impurities. 

Viscosity control agent. It controls and adapts, Increasing or decreasing, viscosity to the required level for optimal chemical and physical stability of the product and dosage in gels, suspensions, emulsions, solutions.

Other uses

• Plastics. Used in the processing of various soft PVC products, such as films, foils, cable materials and moulded products, artificial leather, Cold resistant plasticiser.
• Waterproofing agent in textiles.
• Food packaging with the exception of fatty foods.
• Nitrocellulose varnish, which makes the varnish film with increased elasticity tensile strength.
•  Synthetic rubbers with good softening effect.
• Organic solvent and stationary liquid for gas chromatography (methanol and methylene chloride as solvent with a maximum use temperature of 150°C) separates various oxygenated, aromatic and unsaturated compounds.
• Mineral processing

Sodium oleate studies

Typical commercial product characteristics  Sodium oleate

Appearance	White powder to slightly yellow
Assay	≥99.0%
Boiling Point	359.999ºC at 760 mmHg
Melting Point	232-235°C(lit.)
Flash Point	270.099ºC
Density	0.9 g/cm3
Loss on drying	≤5.0%
Free alkali	≤0.5%
Fatty acid value	195~204
Iodine	80~100 Gl/100g
Shelf life	2 years
Storage	2-8°C
PSA	40.13000
LogP	4.77380
pKa	4.46(at 25℃)
Safety

• Molecular Formula C₁₈H₃₃NaO₂
• Linear Formula    CH₃(CH₂)₇CH=CH(CH₂)₇COONa
  
• Molecular Weight     304.4
• Exact Mass   304.237823
• CAS  143-19-1
• UNII    399SL044HN
• EC Number   205-591-0
• DSSTox Substance ID  DTXSID7021077
• IUPAC  sodium;(Z)-octadec-9-enoate
• InChI=1S/C18H34O2.Na/c1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18(19)20;/h9-10H,2-8,11-17H2,1H3,(H,19,20);/q;+1/p-1/b10-9-; 
• InChl Key      BCKXLBQYZLBQEK-KVVVOXFISA-M
• SMILES   CCCCCCCCC=CCCCCCCCC(=O)[O-].[Na+]
• MDL number  MFCD00004438
• PubChem Substance ID    24898044
• ChEBI  81860
• RXCUI   32559   
• Beilstein      4046357
• RTECS   RK1200000
• HS Code    2916150000

Synonyms

• Oleic acid, sodium salt
• sodium;(Z)-octadec-9-enoate
• Eunatrol
• Sodium 9-octadecenoate
• Olate flakes
• Sodiumoleate
• Sodiumoleate
• sodium (Z)-octadec-9-enoate

References___________________________________________________________________

(1) Norikura T, Mukai Y, Fujita S, Mikame K, Funaoka M, Sato S. Lignophenols decrease oleate-induced apolipoprotein-B secretion in HepG2 cells. Basic Clin Pharmacol Toxicol. 2010 Oct;107(4):813-7. doi: 10.1111/j.1742-7843.2010.00575.x.

(2) Mohamed AMHA, Vladimirovna SN, Grigorievich ZV, Borisovna PA, Ivanovich SV. Sodium Oleate Increases Ampicillin Sensitivity in Methylophilus quaylei Biofilms on Teflon and Polypropylene. Curr Pharm Biotechnol. 2019;20(3):261-270. doi: 10.2174/1389201020666190222191656.

(3) Dong D, Quan E, Yuan X, Xie Q, Li Z, Wu B. Sodium Oleate-Based Nanoemulsion Enhances Oral Absorption of Chrysin through Inhibition of UGT-Mediated Metabolism. Mol Pharm. 2017 Sep 5;14(9):2864-2874. doi: 10.1021/acs.molpharmaceut.6b00851.

Compendium of the most significant studies with reference to properties, intake, effects.

Chen C, Huo JS, Zhuo Q, Li Y, Ma Y, Wang JB, Jia XD. Lipid Accumulation and IL-6 Production in L02 Hepatocytes Induced by Sodium Oleate: Dose and Time Dependence. Biomed Environ Sci. 2021 Dec 20;34(12):998-1004. doi: 10.3967/bes2021.058.

Abstract. To explore interleukin-6 (IL-6) production and characterize lipid accumulation in L02 hepatocytes induced by sodium oleate. 

Zhou S, Zhou W, Dong L, Peng Y, Xie G. Micellization Transformations of Sodium Oleate Induced by Gas Nucleation. Langmuir. 2021 Aug 17;37(32):9701-9710. doi: 10.1021/acs.langmuir.1c01008.

Abstract. The interfacial properties of surfactant solutions are closely related to the micellization of surfactants. Temperature, salt type and concentration, pH, and other parameters affecting the micellization of surfactants have all been extensively investigated previously. However, the effect of dissolved gas on surfactant micellization and associated interfacial properties' transformations is not completely understood yet. In this study, sodium oleate (NaOl) was chosen as the research object, and the role of gas/gas nucleation in NaOl micellization was systematically investigated. 

Tatini D, Raudino M, Ambrosi M, Carretti E, Davidovich I, Talmon Y, Ninham BW, Lo Nostro P. Physicochemical characterization of green sodium oleate-based formulations. Part 1. Structure and rheology. J Colloid Interface Sci. 2021 May 15;590:238-248. doi: 10.1016/j.jcis.2021.01.040.

Abstract. This paper is the first report in which a moderately concentrated (13% w/w) dispersion of NaOL in water is investigated. In fact, at this concentration the phase and rheology behavior of the surfactant remarkably deviates from those of its dilute solutions in water and a significant effect is imparted by the addition of potassium chloride. 

Dong D, Quan E, Yuan X, Xie Q, Li Z, Wu B. Sodium Oleate-Based Nanoemulsion Enhances Oral Absorption of Chrysin through Inhibition of UGT-Mediated Metabolism. Mol Pharm. 2017 Sep 5;14(9):2864-2874. doi: 10.1021/acs.molpharmaceut.6b00851.

Abstract. Sodium oleate (NaOl), a collector in diaspore flotation, has been widely used for more than 30 years, while its low selectivity becomes an issue under today's process requirement. This study introduced tert dodecyl mercaptan (TDM) together with NaOl as a mixed collector to improve selectivity in diaspore flotation.

Sintov A, Ze'evi A, Uzan R, Nyska A. Influence of pharmaceutical gel vehicles containing oleic acid/sodium oleate combinations on hairless mouse skin, a histological evaluation. Eur J Pharm Biopharm. 1999 May;47(3):299-303. doi: 10.1016/s0939-6411(99)00018-1.

Abstract.  It was seen that the severity and frequency of histological changes in the skin treated with OA-containing vehicles were directly correlated with increased pH/ionization (i.e. decreased OA/sodium oleate ratio) and with overall OA concentration.

Llanos S, Giraldo LJ, Santamaria O, Franco CA, Cortés FB. Effect of Sodium Oleate Surfactant Concentration Grafted onto SiO2 Nanoparticles in Polymer Flooding Processes. ACS Omega. 2018 Dec 28;3(12):18673-18684. doi: 10.1021/acsomega.8b02944.

Abstract. The nanotechnology has been applied recently to increase the efficiency of enhanced oil recovery methods. The main objective of this study is to evaluate the effect of SiO2 nanoparticle functionalization with different loadings of sodium oleate surfactant for polymer flooding processes. The sodium oleate surfactant was synthesized using oleic acid and NaCl. 

Barter PJ, Chang LB, Rajaram OV. Sodium oleate promotes a redistribution of cholesteryl esters from high to low density lipoproteins. Atherosclerosis. 1990 Sep;84(1):13-24. doi: 10.1016/0021-9150(90)90003-2. 

Abstract. Cholesteryl esters readily exchanges between the low density lipoproteins (LDL) and high density lipoproteins (HDL) in human plasma in a process of equilibration catalysed by the cholesteryl ester transfer protein (CETP). In the present studies, in which mixtures of human LDL and HDL have been incubated in vitro with partially pure CETP, it has been found that Na oleate disrupts the CETP-mediated equilibrium between LDL and HDL and promotes a concentration dependent redistribution of cholesteryl esters from HDL to LDL.

Beneventi D, Pugh RJ, Carré B, Gandini A. Surface rheology and foaming properties of sodium oleate and C12(EO)6 aqueous solutions. J Colloid Interface Sci. 2003 Dec 1;268(1):221-9. doi: 10.1016/s0021-9797(03)00724-0. 

Abstract. The dynamic surface tension (DST) and the surface viscoelastic modulus of sodium oleate aqueous solutions at different concentrations were measured using an image analysis tensiometer based on the oscillating bubble technique. The diffusion coefficient of oleate moieties was calculated from DST measurements and the surface viscoelastic modulus using the Langmuir-Szyszkowski and the diffusion-controlled adsorption models. 

Okumura T, Suzuki K, Kumada K, Kobayashi R, Fukuda A, Fujii C, Kohama A. Severe respiratory distress following sodium oleate ingestion. J Toxicol Clin Toxicol. 1998;36(6):587-9. doi: 10.3109/15563659809028053. 

Abstract. Oleic acid and oleate are pulmonary toxins used to create laboratory models of acute respiratory distress syndrome, but there is little information on human toxicity. We report the intentional ingestion of 50 mL sodium oleate 20% by a 22-year-old woman with no symptoms for the first 2 days after ingestion.

Kameshima Y, Sasaki H, Isobe T, Nakajima A, Okada K. Synthesis of composites of sodium oleate/Mg-Al-ascorbic acid-layered double hydroxides for drug delivery applications. Int J Pharm. 2009 Oct 20;381(1):34-9. doi: 10.1016/j.ijpharm.2009.07.021. 

Abstract. Mg-Al-ascorbic acid (ASA)-layered double hydroxides (ASA-LDHs) with Mg/Al=3 were synthesized by ion-exchange, coprecipitation and reconstruction methods. Composites with sodium oleate (SOA)/ASA-LDH were prepared by an ion-exchange method using various concentrations of SOA solutions. 

Guedes IS, Stencel M, Campello AD, do Nascimento AJ. Effect of sodium oleate on oxidative metabolism of isolated mitochondria and submitochondrial particles. An Acad Bras Cienc. 1982 Mar;54(1):233-9. 

Abstract. Using conventional polarographic and spectrophotometric methods, the effect of sodium oleate on isolated mitochondria dn submitochondrial particles was analysed. A loose coupling was developed in isolated mitochondria in the presence of about 10 nmoles oleate per mg protein. Oleate stimulates and activity of bovine heart mitochondrial Mg-ATPase, and it was found to be dependent on substrate concentration. Investigation of the membrane potential showed that the delta psi is abolished at high concentration of oleate. The deterioration of the morphological appearance of mitochondria, occurring on addition of oleate, is also described.