CAS 1338-41-6 Sorbitan Stearate - Vaccine Lab / Alfa Chemistry

The Role of Sorbitan Stearate in Vesicle Formation and Interactions with Trehalose

Influence of trehalose on the interaction of curcumin with surface active ionic liquid micelle and its vesicular aggregate composed of a non-ionic surfactant sorbitan stearate Roy A, et al. Chemical Physics Letters, 2016, 665, 14-21.

This study reveals that Sorbitan Stearate (Span 60), in combination with 1-hexadecyl-3-methylimidazolium chloride ([C16mim]Cl), effectively forms stable vesicular assemblies that interact dynamically with trehalose. The trehalose-modified vesicles alter the microenvironment and hydrogen bonding of encapsulated curcumin, enhancing its stability and photophysical properties. The findings highlight important aspects of sugar-nonlipidic membrane interactions, providing insights into designing novel vesicle-based delivery systems using nonionic surfactants like Sorbitan Stearate.
Methodology: [C16mim]Cl micellar solutions were prepared at a concentration of 0.02 M. Different ratios of Sorbitan Stearate (Span 60) were added to the micellar solution to create vesicular assemblies, with varying molar ratios (R values ranging from 0 to 0.9). The vesicular solutions were formed by sonication at 298 K. Dynamic light scattering (DLS) and transmission electron microscopy (TEM) were employed to study the vesicle size and morphology, while fluorescence spectroscopy was used to analyze the dynamic properties of curcumin within these systems.
Results: The study confirms that trehalose significantly influences the characteristics of [C16mim]Cl-Span 60 vesicles. DLS and TEM measurements reveal that the presence of Sorbitan Stearate in [C16mim]Cl solutions facilitates vesicle formation, and the addition of trehalose leads to a substantial increase in vesicle size. Trehalose molecules interact with the bilayer surface of the SAIL-Span 60 vesicles, enhancing the vesicle stability and influencing their structural properties.

Sorbitan Stearate for Improving Cold Flow Properties of Shea Butter Biodiesel

Improving the cold-flow properties of shea butter biodiesel by additive winterization Simon Ubengi Elnour Bagini, et al. Industrial Crops and Products, 2024, 210, 118156.

The use of sorbitan stearate (Span 60) as an additive was effective in enhancing the low-temperature flow properties of shea butter biodiesel. Compared to sorbitan palmitate (Span 40), sorbitan stearate showed a higher efficiency in reducing the cloud point while increasing the liquid recovery rate.
Methodology: Shea butter biodiesel was produced via transesterification of shea butter with methanol, using sulfuric acid (H₂SO₄) as a catalyst. The optimum conditions for methyl ester conversion, with a yield of 99.54 wt%, were achieved using 0.5 wt% H₂SO₄ and 1.2 wt% potassium hydroxide (KOH). The esterification process involved preheating the feedstock, adding methanol and H₂SO₄ to the mixture, and agitating it at 333 K for 1 hour. After settling and separation, the neutralized esterified mixture underwent further reaction with KOH-methanol to complete the transesterification process.
This nonionic surfactant, at concentrations of 0.5-1.0 wt%, was added to the biodiesel, and the mixture was cooled to temperatures between the cloud point (CP) and pour point (PP) of the biodiesel. A significant improvement was observed in the cold-flow properties, with a reduction in CP by 8-10 K at a cooling temperature of 294 K.
Results and Conclusion: The use of sorbitan stearate as an additive was effective in enhancing the low-temperature flow properties of shea butter biodiesel. Compared to sorbitan palmitate (Span 40), sorbitan stearate showed a higher efficiency in reducing the cloud point while increasing the liquid recovery rate. The findings suggest that converting shea butter to biodiesel using a two-step acid-alkali reaction, followed by additive winterization with 0.5-1.0 wt% sorbitan stearate, is a promising strategy for producing biodiesel with improved cold-flow properties suitable for colder climates.

Sorbitan Stearate for Surface Modification of Tourmaline Powder

The surface organic modification of tourmaline powder by span-60 and its composite. Hu Y, et al. Applied Surface Science, 2012, 258(19), 7540-7545.

The use of sorbitan stearate (Span-60) effectively modified the surface of tourmaline, significantly enhancing its hydrophobic properties and compatibility with polymer matrices like polypropylene. This modification not only improved the dispersion stability of tourmaline in the polymer but also increased the release of beneficial negative ions, making Span-60 an effective surfactant for such applications.
Methodology: The surface modification of superfine tourmaline powder was performed by reacting 5 g of tourmaline with 3% (by mass) of Span-60 in 50 ml of toluene at 60 °C for 1 hour. After the reaction, the mixture was separated by centrifugation, washed with ethanol and acetone, and then dried. The modification effects were analyzed by measuring the activation index and contact angle. The activation index approached 100%, and the contact angle increased from 0° to approximately 125°, indicating enhanced hydrophobic properties.
Reaction Mechanism: Span-60 modifies tourmaline through a transesterification reaction with the hydroxyl groups on the surface of the tourmaline particles. This reaction introduces long hydrophobic alkyl groups onto the tourmaline surface, reducing its polarity while preserving the original crystal structure. The modified tourmaline exhibited a 2.4-fold increase in the release of negative ions compared to unmodified tourmaline.
Results and Discussion: The hydrophobic modification significantly improved the dispersion stability of tourmaline in polypropylene. Scanning Electron Microscope (SEM) images of the modified tourmaline/PP composite demonstrated a much better dispersancy than that of the unmodified tourmaline composite. Additionally, the amount of negative ions released from the modified tourmaline/PP composite was greater than that from the unmodified one, enhancing its functional properties.

Sorbitan Stearate (Span 60) in Niosome Formulation for α-Tocopherol Delivery

Physicochemical properties and release behavior of Span 60/Tween 60 niosomes as vehicle for α-Tocopherol delivery Basiri L, et al. LWT, 2017, 84, 471-478.

This study explores the use of Span 60 in niosomes as vehicles for α-Tocopherol (α-Toc) to enhance its availability and stability. The study concludes that the combination of Span 60 and Tween 60 in a 3:1 molar ratio, along with Chol and DCP, provides an optimal formulation for the encapsulation of α-Tocopherol in niosomes. The formulation exhibited high encapsulation efficiency, improved stability, and controlled release properties, making it suitable for enhancing the bioavailability of α-Toc in pharmaceutical applications.
Methodology: Niosomes were prepared using a modified thin-film hydration method. A specific molar ratio of Span 60 and Tween 60, dissolved in a 1:2 ethanol mixture, was used as the wall material. The solvent was evaporated under reduced pressure using a rotary evaporator, and the resultant thin film was hydrated with phosphate-buffered saline. The vesicle suspension was then sonicated to form unilamellar vesicles.
Results and Discussion: The optimal formulation of α-Toc-loaded niosomes was achieved with a 3:1 molar ratio of Span 60 to Tween 60, along with a 25:12.5:2.5 M ratio of surfactant:Chol
, and 4 mg/mL of α-Toc. This combination provided the highest encapsulation efficiency (83.22% to 99.07%) and smallest mean particle size (106.8 to 190 nm). The presence of Chol and DCP significantly enhanced the physicochemical stability and reduced the size distribution. However, increasing the hydrophilic-lipophilic balance (HLB) by altering the surfactant ratio led to a decrease in both EE and niosome stability.
The in vitro release study demonstrated an initial burst release of α-Toc, followed by a sustained release profile, which is advantageous for controlled drug delivery systems. The use of Span 60 in the optimized formulation resulted in niosomes with excellent stability, narrow size distribution, and high encapsulation efficiency.

Sorbitan Stearate in Perfluorocarbon-Filled Microbubble Formulations

Novel ultrasound contrast agent based on microbubbles generated from surfactant mixtures of Span 60 and polyoxyethylene 40 stearate Xing Z, et al. Acta Biomaterialia, 2010, 6(9), 3542-3549.

Novel perfluorocarbon (PFC)-filled microbubbles were developed using ultrasonication of a surfactant mixture containing sorbitan stearate (Span 60) and polyoxyethylene 40 stearate (PEG40S) in aqueous media. The combination of these surfactants produced microbubbles with optimal size, stability, and echogenicity, suitable for ultrasound imaging applications. Further research is warranted to explore dose-response curves and potential applications in tumor vascularity imaging.
Methodology: The microbubbles were prepared by dissolving Span 60 (900 mg), PEG40S (475 mg), and NaCl (900 mg) in 30 mL of phosphate-buffered saline (PBS, pH 7.4). After mixing and autoclaving, the solution was sonicated at the air-water interface with constant purging of PFC gas in an ice bath for 3 minutes. The sonication resulted in a polydisperse suspension, which was then allowed to stand for 60 minutes. This process led to the formation of three distinct layers: a top foam layer of large bubbles, a middle opaque layer of microbubbles, and a bottom layer of residual surfactants. The microbubbles, with an average diameter of 2.08 ± 1.27 μm, were separated, washed, and stored in PBS buffer solution under a gas headspace.
Results and Discussion: More than 99% of the prepared microbubbles exhibited a mean particle diameter of less than 8 μm, making them suitable for intravenous administration as ultrasound contrast agents. The surface pressure-area (π-A) isotherms indicated strong interactions between Span 60 and PEG40S, forming a monolayer shell that significantly reduced surface tension and provided a mechanical surface pressure. This shell hindered gas escape from the microbubble core, enhanced stability, and prevented aggregation.
The study demonstrated that Span 60 forms a condensed monolayer with low surface tension and high surface pressure, which is crucial in stabilizing microbubbles against dissolution.

Catalog Number	ACM1338416-2
CAS	1338-41-6
Structure
Description	Emulsifying agent derived from sorbitol and stearic acid. Saponification value 147-157. HLB value 4.7 (gives water-in-oil emulsions).
Synonyms	Span 60;Sorbitan, esters, monooctadecanoate;Sorbitan, monooctadecanoate;Sorbitan, monostearate;Sorbitan monostearate;Anhydrosorbitol monostearate
IUPAC Name	[(2R)-2-[(2R,3R,4S)-3,4-dihydroxyoxolan-2-yl]-2-hydroxyethyl] octadecanoate
Molecular Weight	430.62
Molecular Formula	C24H46O6
Canonical SMILES	CCCCCCCCCCCCCCCCCC(=O)OC[C@H]([C@@H]1[C@@H]([C@H](CO1)O)O)O
InChI	HVUMOYIDDBPOLL-XWVZOOPGSA-N
InChI Key	InChI=1S/C24H46O6/c1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-22(27)29-19-21(26)24-23(28)20(25)18-30-24/h20-21,23-26,28H,2-19H2,1H3/t20-,21+,23+,24+/m0/s1
Boiling Point	465 °C
Melting Point	54-57 °C(lit.)
Purity	99%+
Density	1.0g/ml
Solubility	Partly soluble in alcohols, insoluble in water & oils
Appearance	Pale-yellow pellets, odorless
Application	Lotions, creams, ointments, various makeup products.
Storage	Store in a closed container at a dry place at room temperature
Complexity	417
Composition	Sorbitan monostearate
Covalently-Bonded Unit Count	1
Defined Atom Stereocenter Count	4
Exact Mass	430.32943918
Heavy Atom Count	30
Hydrogen Bond Acceptor Count	6
Hydrogen Bond Donor Count	3
Isomeric SMILES	CCCCCCCCCCCCCCCCCC(=O)OC[C@H]([C@@H]1[C@@H]([C@H](CO1)O)O)O
Monoisotopic Mass	430.32943918
Physical State	Solid
Rotatable Bond Count	20
Topological Polar Surface Area	96.2 Å²