Lanolin

The main derivatisation routes include hydrolysis, fractional solvent crystallisation, esterification, hydrogenation, alkoxylation and quaternisation.

Lanolin alcohols are a rich source of cholesterol (an important skin lipid) and are powerful water-in-oil emulsifiers; they have been used extensively in skincare products for over 100 years.

The wool grease is continuously removed during this washing process by centrifuge separators, which concentrate it into a waxlike substance melting at approximately 38 °C (100 °F).

Commercial products (e.g. Lanocote) containing up to 85% lanolin[12] are used to prevent corrosion in marine fasteners, especially when two different metals are in contact with each other and saltwater.

Anhydrous liquid lanolin, combined with parabens, has been used in trials as artificial tears to treat dry eye.

Lanolin can also be restored to woollen garments to make them water and dirt repellent, such as for cloth diaper covers.

This requirement, which is generally regarded as the new quality standard, extends the list of pesticides to 40 and imposes even lower concentration limits.

These ultra-high-purity grades of lanolin are ideally suited to the treatment of dermatological disorders such as eczema and on open wounds.

[17] A study carried out at New York University Hospital in the early 1950s had shown about 1% of patients with dermatological disorders were allergic to the lanolin being used at that time.

By one estimate, this simple misunderstanding of failing to differentiate between the general healthy population and patients with dermatological disorders exaggerates the sensitising potential of lanolin by 5,000–6,000 times.

Modern analytical methods have revealed lanolin possesses a number of important chemical and physical similarities to human stratum corneum lipids; the lipids which help regulate the rate of water loss across the epidermis and govern the hydration state of the skin.

[2][19][20] Cryogenic scanning electron microscopy has shown that lanolin, like human stratum corneum lipids, consists of a mass of liquid crystalline material.

[3] When applied daily at around 4 mg/cm2 for five consecutive days, the positive moisturizing effects of lanolin were detectable until 72 hours after final application.

[2] In a small clinical study conducted on volunteer subjects with terribly dry (xerotic) hands, lanolin was shown to be superior to petrolatum in reducing the signs and symptoms of dryness and scaling, cracks and abrasions, and pain and itch.

In another study, a high purity grade of lanolin was found to be significantly superior to petrolatum in assisting the healing of superficial wounds.