1-Hexadecanol (Cetyl Alcohol) is a long chain fatty alcohol. It is a long chain fatty alcohol and it is also called palmityl alcohol, discovered by the chemist Michel Chevreul in France in 1817.

The name describes the structure of the molecule:

• Cetyl is derived from the Latin "cetus", meaning whale. Cetyl alcohol was originally isolated from whale oil, but today it is primarily produced from vegetable oils and petroleum.

Raw Materials Used in Production.

• Oils and fats, notably palm oil or coconut oil, are often the primary source for cetyl alcohol.

Step-by-step Summary of Industrial Production Process.

• Hydrogenation: Fatty acids obtained from oils and fats are subjected to a hydrogenation process.
• Reduction: The resulting fatty acid esters are then reduced with hydrogen in the presence of a catalyst to form alcohols, including cetyl alcohol.
• Distillation: Cetyl alcohol is then separated from the other alcohols via distillation.
• Refinement: It is further purified to remove any remaining impurities.

Form and Color.

Cetyl alcohol typically appears as a white wax or flakes.

 What is it for?

It is a chemical substance frequently used in cosmetics as a non-ionic emollient, emulsifier or thickening agent as a pharmaceutical excipient and in medicine.

Cosmetics

Skin conditioning agent - Emollient. Emollients have the characteristic of enhancing the skin barrier through a source of exogenous lipids that adhere to the skin, improving barrier properties by filling gaps in intercorneocyte clusters to improve hydration while protecting against inflammation. In practice, they have the ability to create a barrier that prevents transepidermal water loss.  Emollients are described as degreasing or refreshing additives that improve the lipid content of the upper layers of the skin by preventing degreasing and drying of the skin. The problem with emollients is that many have a strong lipophilic character and are identified as occlusive ingredients; they are oily and fatty materials that remain on the skin surface and reduce transepidermal water loss. In cosmetics, emollients and moisturisers are often considered synonymous with humectants and occlusives.

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.

Emulsion stabiliser. Emulsions are thermodynamically unstable. Emulsion stabilisers improve the formation and stability of single and double emulsions. as well as their shelf-life. It should be noted that in the structure-function relationship, the molar mass of the ingredient used plays an important role.

Surfactant - Foam booster. It has the effect of introducing gas bubbles into the water and affects the cleaning process by helping to spread the cleanser. Since sebum has an inhibiting effect on the bubble, more foam is produced in the second shampoo.

Fragrance. It plays a very important role in the formulation of cosmetic products as it provides the possibility of enhancing, masking or adding fragrance to the final product, increasing its marketability. It is able to create a perceptible pleasant odour, masking a bad smell. The consumer always expects to find a pleasant or distinctive scent in a cosmetic product. 

Opacifying agent. It is useful into formulations that may be translucent or transparent to make them opaque and less permeable to light.

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. 

Commercial Applications:

Cosmetics Industry. Cetyl alcohol is widely used in cosmetics as an emollient, emulsion stabilizer, and thickener. It's often found in creams, lotions, and hair conditioners.

Pharmaceutical. It can be used as an auxiliary agent in the formulation of medicinal creams and ointments.

Soap Production. Cetyl alcohol can be used to enhance the consistency and emulsifying properties of soaps.

Food Industry. While less common, it can be used as an additive in some food formulations.

Most significant studies

Cetyl alcohol has been used to produce soporolipids, glycolipid biosurfactants that have been shown to exhibit antitumor activity (1).

Drug release. Based on this study, it can be concluded that cetyl alcohol microspheres and indomethacin capsule (Microcid SR) capsule are bioequivalent in terms of the rate and extent of absorption (2).

The protective effects of synthetic lung surfactant Exosurf® (containing cetyl alcohol) against endotoxin-induced inflammation have been demonstrated (3).

• Molecular Formula   C₁₆H₃₄O   or   [CH₃(CH₂)₁₄CH₂OH]
• Molecular Weight   242.447 g/mol
• CAS 36653-82-4
• EINECS 253-149-0

Synonyms

• cetylalcohol
• 1-Hexadecanol
• Hexadecan-1-ol
• Normal primary hexadecyl alcohol
• N-Hexadecanol
• n-Hexadecyl alcohol
• n-1-Hexadecanol
• Loxanwachs SK
• Crodacol C

References_______________________________________________________________________

(1) Nawale L, Dubey P, Chaudhari B, Sarkar D, Prabhune A. Anti-proliferative effect of novel primary cetyl alcohol derived sophorolipids against human cervical cancer cells HeLa.  PLoS One. 2017 Apr 18;12(4):e0174241. doi: 10.1371/journal.pone.0174241. eCollection 2017.

Abstract. Sophorolipids (SLs) are glycolipid biosurfactants that have been shown to display anticancer activity. In the present study, we report anti-proliferative studies on purified forms of novel SLs synthesized using cetyl alcohol as the substrate (referred as SLCA) and their anticancer mechanism in human cervical cancer cells. Antiproliferative effect of column purified SLCA fractions (A, B, C, D, E and F) was examined in panel of human cancer cell lines as well as primary cells. Among these fractions, SLCA B and C significantly inhibited the survival of HeLa and HCT 116 cells without affecting the viability of normal human umbilical vein endothelial cells (HUVEC). The two fractions were identified as cetyl alcohol sophorolipids with non-hydroxylated tail differing in the degree of acetylation on sophorose head group. At an IC50 concentration SLCA B (16.32 μg ml-1) and SLCA C (14.14 μg ml-1) blocked the cell cycle progression of HeLa cells at G1/S phase in time-dependent manner. Moreover, SLCA B and SLCA C induced apoptosis in HeLa cells through an increase in intracellular Ca2+ leading to depolarization of mitochondrial membrane potential and increase in the caspase-3, -8 and -9 activity. All these findings suggest that these SLCAs could be explored for their chemopreventive potential in cervical cancer.

(2) Gupta NV, Gowda DV, Balamuralidhara V, Khan MS. Preparation and Comparative Bioavailability Studies of Indomethacin-Loaded Cetyl Alcohol Microspheres.  J Pharm (Cairo). 2013;2013:109837. doi: 10.1155/2013/109837. 

Abstract. The purpose of the present study was to compare the in vitro release and to find out whether the bioavailability of a 75 mg indomethacin capsule (Microcid SR) was equivalent to optimized formulation (indomethacin-loaded cetyl alcohol microspheres). Indomethacin-loaded cetyl alcohol microspheres were prepared by meltable emulsified cooling-induced technique. Surface morphology of microspheres has been evaluated using scanning electron microscopy. A single dose, randomized, complete cross over study of IM microspheres was carried out on 10 healthy male and female Albino sheep's under fasting conditions. The plasma was separated and the concentrations of the drug were determined by HPLC-UV method. Plasma indomethacin concentrations and other pharmacokinetic parameters obtained were statistically analyzed. The SEM images revealed the spherical shape of fat microspheres, and more than 98.0% of the isolated microspheres were in the size range 12-32 μm. DSC, FTIR spectroscopy and stability studies indicated that the drug after encapsulation with fat microspheres was stable and compatible. Both formulations were found to be bioequivalent as evidenced by in vivo studies. Based on this study, it can be concluded that cetyl alcohol microspheres and Microcid SR capsule are bioequivalent in terms of the rate and extent of absorption.

(3) Bi L, Wehrung D, Oyewumi MO. Contributory roles of innate properties of cetyl alcohol/gelucire nanoparticles to antioxidant and anti-inflammation activities of quercetin.  Drug Deliv Transl Res. 2013 Aug;3(4):318-29. doi: 10.1007/s13346-013-0130-6.

Abstract. The protective effects of synthetic lung surfactant Exosurf® (containing cetyl alcohol) against endotoxin-induced inflammation have been demonstrated in the literature. Thus, it is envisioned that nanoparticles loaded with quercetin (Q-NPs) prepared with binary mixtures of cetyl alcohol (CA) and Gelucire 44/14® (gelucire) as matrix materials will be capable of overcoming some of the protracted challenges confronting clinical application of quercetin and possess innate protective activity against inflammatory responses, which could be synergistic with quercetin. The NPs were stable in simulated biological media while retaining their particle size and spherical morphology. Further analysis by gel permeation chromatography, spectroscopic analysis (ultraviolet-visible, fluorescence, and Fourier transform infrared spectroscopy) indicated entrapment of quercetin in NPs. Q-NPs effectively enhanced xanthine oxidase inhibitory and free radical scavenging effect of quercetin. Furthermore, Q-NPs showed marked reduction (compared to quercetin alone) in production of nitric oxide and cytokine (interleukin-6 and tumor necrosis factor alpha) from lipopolysaccharide-activated macrophages. Superiority of Q-NPs over quercetin alone was confirmed from in vivo anti-inflammatory efficacy studies in BALB/c mice. Data from additional studies with blank NPs (without quercetin) showed that the NPs reported herein most likely possessed intrinsic protective properties against LPS-induced inflammation. Although further mechanistic studies are warranted, the overall work depicted a novel approach of possible exploiting innate protective properties of NPs in quercetin delivery for treating oxidative stress and inflammation.