Introduction
Nanotechnology has been widely used in many branches like the cosmetics, medical, pharmaceutical, and food sectors because of its effectiveness, product stability, and safety. Nanoemulsion is a mixture of small particles of liquid in a dispersed phase (oil or water) in another base liquid in dispersing medium (surfactant) mainly used to deliver compact active, reagents in the controlled process, these liquids are stable containing a combination of oil, water phase with surfactant.
What Are the Preparation Methods and Composition of Nanoemulsions?
Nanoemulsion can be prepared by using high-pressure homogenization. It is a method in which high pressure is passed in the tank of product, which creates a small particle of uniform size of approximately 1 nm. The other method is microfluidization which is a mixing device with high pressure. It consists of microchannels. The product is passed through it, which is then filtered to create the small uniform size of nanoemulsion. The emulsion can be composed of oil, surfactants like solubilizing agents, adsorption enhancers, and aqueous media like water, glycerine, ethanol, and propanol.
What Is the Use of Nanoemulsion in Cosmetics?
Nanoemulsions have gained much popularity by the manufacturers as they help maintain the stability of the product. Because of the fine droplet particles, they can spread in the larger area easily. The active ingredient can penetrate the skin better and reduce water loss from the body through the skin. Nanoemulsion helps in increased absorption of the product. They are available in water-oil concentrations and helpful in topical, oral, and injectable mode for product use. They are insoluble in water. The fine particles help them to give the product a transparent look; they require less amount of surfactant compared to microemulsion, help in increasing the bioavailability of the product, and the absorption of active ingredient is faster and efficient and can be easily used by the consumer.
They are widely known for their property of spreading to large surface areas with small volumes; because of these properties, they are widely used in sunscreen creams and moisturizing creams. Nanoemulsions help in increasing the shelf life of products with controlled release of the active ingredient. They are available in a variety of formulations in the form of cream, liquid, gel, foam, and sprays. These formulations are made without irritation and toxicity that can be easily applied to the skin without itching and burning sensation on the mucous membrane.
What Are the Types of Nanoemulsions Used in Cosmetics?
A variety of nanoemulsions are used in beauty products like fairness cream, makeup base products, and lipsticks. Nanoemulsions are used to make colored makeup products. Like gold nanoparticles give red or blue coloration, silver nanoparticles give yellow coloration, and gold-silver nanocomposites give orange color. They are also used in skin whitening cosmetic products giving desired skin tone.
Nanoemulsions are used in lip care products like lip gloss, lipstick, lip balm, and liner to retain moisture in lips. Silver and gold nanoemulsions are used to give color to lipstick in various modulations for long-lasting lipstick.
Nanoemulsions are also used in hair care products like oil, shampoo, conditioner, serum, gel, and spray to prevent hair fall and hair growth, improving the texture of hair, ammonium salts are added to give shine, softness, and smoothness to hair, silver, gold, copper, and other nanoparticles are used for hair coloring.
How Are Nanoemulsions Delivered?
Nanoemulsions have many properties and advantages, and because of that, they are used extensively; nanoemulsions are available in various forms, like parenteral drugs, oral and topical modes, and ocular and pulmonary modes. Nanoemulsions are used in biotechnology for an enzymatic chain reaction and the synthesis of ester, peptides, and sugar acetyl. Also used in hydrolysis reactions, steroid reactions, and used in disinfectant cleaners used in hospitals, and healthcare centers; as the particles are fine, they are less or no irritant to eyes and skin.
-
The parenteral mode of drug administration with nanoemulsion is far more effective than macro and microemulsion, as nanoemulsion particles are fine; they are easily absorbed and transported into the system and are much more effective as they are slowly cleared out. They are also used in vaccines as a vehicle to transport protein to the mucosal surface to fasten the absorption of antigens in cells.
-
Oral and topical mode of delivery helps in easy absorption with less drug toxicity with efficient potency. They are ideally used with steroids, antibiotics, diuretics, and hormone formulations. They are easily penetrated through the skin because of the fine droplet size and are absorbed better.
-
Ocular and pulmonary mode for eye and lung diseases in the form of eye drops and nasal spray. The fine drop of nanoemulsion is easily absorbed, helping in the solubility of carrier drugs that are poorly dissolved.
What Is the Disadvantage of Nanoemulsion?
Due to the extensive use of nanoemulsion in multisector giving promising results, a concern has been raised by several governments and non-government bodies on use. Guidelines have been proposed by the European Commission and Food and Drug Administration on use. The use of nanoemulsion is registered under research, evaluation, authorization, and restriction of chemicals aiming to utilize safe usage.
-
A large concentration of surfactant is a must for balancing nanodroplets to avoid toxicity.
-
Because of its property to cover the high surface area to the volume of nanoparticle ratio and small particles, it becomes highly reactive, which can raise toxicity.
-
Due to the excellent penetration properties, the toxicity spreads fast into the system, leading to adverse effects.
-
The nanoparticles can permeate through the skin into the bloodstream and are absorbed into the skin. Blood supplying organs, the pulmonary tract, and the brain, which can be advantageous or disadvantageous depending upon the toxicity of surfactant present in it, causing benefit or harm to the body.
-
Studies have shown titanium oxide and zinc oxide nanoparticles used in sunscreen can absorb ultraviolet rays and cause harm to the skin leading to cell destruction and skin cancer; traces of titanium dioxide nanoparticles were also found in brain cells, which leads to brain damage.
-
Research has also found free radicals of aluminum oxide nanoparticles lead to stem cell toxicity and the destruction of brain blood vessel cells.
Conclusion
Cosmetic nanoemulsion has shown promising results over the years and is used extensively by manufacturers for its benefits, but still, there is not much data available on its adverse effect, so one must use these products mindfully with the advice of a healthcare provider.
