Eco-friendly sunscreen formulation based on starches and PEG-75 lanolin increases the antioxidant capacity and the light scattering activity in the visible light

Author(s)

Infante, Victor Hugo Pacagnelli ^{[1, 2, 3, 4, 5]} ; Lohan, Silke B. ^{[2, 3, 4, 5]} ; Schanzer, Sabine ^{[2, 3, 4, 5]} ; Campos, Patricia Maria Berardo Gonsalves Maia ^[1] ; Lademann, Juergen ^{[2, 3, 4, 5]} ; Meinke, Martina C. ^{[2, 3, 4, 5]}

Affiliation

^[1] Univ Sao Paulo, Sch Pharmaceut Sci Ribeirao Preto, Av Cafe S-N, BR-14040900 Ribeirao Preto, SP - Brazil

^[2] Charite Univ Med Berlin, Charite Pl 1, D-10117 Berlin - Germany

^[3] Free Univ Berlin, Charite Pl 1, D-10117 Berlin - Germany

^[4] Humboldt Univ, Charite Pl 1, D-10117 Berlin - Germany

^[5] Berlin Inst Hlth, Dept Dermatol Venereol & Allergol, Charite Pl 1, D-10117 Berlin - Germany

• Document type: Journal article
• Source: JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY; v. 222, SEP 2021.
• Web of Science Citations: 0

Abstract

Most modern sunscreens contain physical filters, which scatter the sunlight, increasing the photons' pathway in the upper stratum corneum. This effect can lead to a better efficacy of the UV filters and improve the diffuse reflection. However, the addition of nanosized inorganic UV filters reduces the antioxidant capacity of sunscreen formulations. Two cream formulations (F1, F2) which differ in the ingredient PEG75 Lanolin (F2), have been characterized for their radical protection factor (RPF) and their optical properties in vitro using electron paramagnetic resonance (EPR) spectroscopy and UV/VIS spectrometry. The RPF for PEG-75 Lanolin was also determined. Furthermore, their radical protection properties were analyzed on porcine skin ex vivo after visible light irradiation by EPR. The structure of each formulation in the skin surface was determined by reflectance confocal microscopy in vivo. The addition of lanolin increased the reflectance and reduced the transmittance for visible light, improving the scattering drastically. Besides, the antioxidant capacity was also increased for F2, something unpublished until now. F1 presented a lower scattering provided by starches. The sunscreens showed high scattering properties and antioxidant capacity, especially for F2, which presented the lowest radical formation in the skin model. These results are consistent with the RPF measurements where F2 has a higher RPF value (193 + 3 x 10(14) radicals/mg) than F1 (155 + 4 x 10(14) radicals/mg) and for PEG-75 Lanolin (37 + 1 x 10(14) radicals/mg). The combination of starches and PEG-75 Lanolin is the first solution to provide both, light scattering and antioxidant capacity, in sunscreens. (AU)

• FAPESP's process: 16/13705-0 - Research and development of cosmetic products for the male audience with essential oils: characterization of skin, clinical efficacy, consumer profile and influence of advertising
• Grantee: Victor Hugo Pacagnelli Infante
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 19/12452-0 - Raman microscopy and spectroscopy: non-invasive techniques to evaluate skin penetration and free radical formation of cosmetic formulations
• Grantee: Victor Hugo Pacagnelli Infante
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate (Direct)