Historically, cosmetics and personal care products have been made with naturally occurring organic compounds. However, many inorganic compounds have found a place in the personal care product industry. Inorganic compounds are now common ingredients in sunscreens, shampoos, and makeup. In regards to inorganic materials enhanced longevity, increased product performance, preservative applications, and decreased health risks are possible attributes. Inorganic materials have so far been very advantageous in cosmetic and personal care formulation and have been used in various applications. One of the biggest successes could arguably be the use of ZnO and TiO2 in sunscreens. Despite successes researchers …show more content…
Since then nanoparticles have become increasingly used in the cosmetic industry. In 2013 it was estimated that over 1300 products worldwide were formulated with nanotechnology. Nanoparticles are currently used worldwide in the formulation of products such as lipsticks, moisturizers, shampoos, and sunscreens. In the cosmetic industry three main forms of nanotechnology are used: nanoparticles, nanocapsules, and nanospheres. The definition of nanoparticles is debated but they can be loosely classified as particles in the nanoscale region. Nanocapsules consist of a cosmetic ingredient enclosed by a polymeric membrane, and nanospheres are composed of a cosmetic ingredient dispersed through a sphere (see above picture) [4]. Solid lipid nanoparticles (SLN) have also been found to be especially useful in the formulation industry. Solid lipid nanoparticles differ in their composition and preparation methods. In the most general terms they are composed of solid lipid, emulsifiers, and water/solvent [7]. They can be prepared by various techniques including, but not limited to, high shear homogenization, hot homogenization, cold homogenization, high speed homogenization, solvent emulsification/evaporation, micro emulsion, supercritical fluid, spray drying, or double emulsion. Currently, solid lipid nanoparticles are being increasingly used as a topical delivery method for drugs, and active ingredients in cosmetic products …show more content…
Smaller particle sizes of titanium dioxide and zinc oxide (approximately 20nm) have proven to be more effective at reflecting and scattering UV radiation [4]. In order to determine that the SPF increases when nanosized particles of ZnO and TiO2 are used, spectral scans of ZnO and TiO2 were performed using a UV-2000S Ultraviolet Transmittance Analyzer [6]. A transpore tape substrate was used as a blank, and then the sunscreen was applied before obtaining another spectra. This method allows quantification of the changes in SPF from micro particle to nanoparticle formulas. The results obtained from these scans show that the SPF did increase with nanosized particles of ZnO and TiO2 (Figure 6.1). In this study ZnO increased by about one SPF factor, while the TiO2 SPF more than doubled when using nanosized particles. In addition to increased SPF results, nanosized particles decreased the traditional “white look” sunscreen gives when applied to the skin