Diethyl sinapate-grafted cellulose nanocrystals as nature-inspired UV filters in cosmetic formulations

Abstract

Inspired by nature’s photoprotection mechanisms, we report an effective UV-blocking nanomaterial based on diethyl sinapate-grafted cellulose nanocrystals (CNC-DES). The colloidal stability and UV-blocking performance of CNC-DES in aqueous glycerol (a common humectant in petroleum-free cosmetic formulations) and in a commercially available moisturizing cream were studied. Grafting the water-insoluble DES onto CNCs renders it dispersible in these water-based formulations, thanks to the excellent water-dispersibility of CNC nanoparticles. Glycerol dispersions containing 0.1 to 1.5 wt% CNC-DES display very high UV-blocking activity owing to the anti-UV DES moieties anchored onto CNCs. A facial cream blended with 1.5 wt% CNC-DES exhibits an SPF of 5.03, which is higher than a commercially available sunscreen with the same active ingredient concentration (SPF = 3.84). DPPH radical scavenging assay also showed the antioxidant potential of CNC-DES, albeit coinciding with a significant reduction in antioxidant activity after grafting DES onto CNCs. Cytotoxicity measurements revealed the CNC-DES not to cause significant cytotoxicity to murine fibroblast cells after 24 h of exposure. Overall, CNC-DES exhibits strong anti-UV and antioxidant properties and is water-dispersible, biocompatible, non-greasy, and lightweight. This study demonstrates the exceptional potential of DES-grafted CNCs as nature-inspired UV filters in the next generation of cosmetic formulations, including those for sensitive skins.

Thermoresponsive Poly(N-isopropylacrylamide) Grafted from Cellulose Nanofibers via Silver-Promoted Decarboxylative Radical Polymerization

“…Figure b,c shows the XPS C 1s spectra of TEMPO-oxidized CNF and PNIPAM-g-CNFs (1 equiv Ag). Both materials exhibit four characteristic peaks typical for carboxylated cellulose: C1: C–C and C–H at 285 eV, C2: C–O at 286.5 eV, C3: O–C–O, CO, and COO– at 288 eV, and C4: −COOH at 289 eV. − PNIPAM-g-CNFs showed two new peaks at 285.5 and 287.5 eV associated with the C–N and N–C–O binding energies of PNIPAM, respectively. This was accompanied by a significant increase in %C1 as PNIPAM chains were grafted from CNFs.…”

From Biomass-Derived p-Hydroxycinnamic Acids to Novel Sustainable and Non-Toxic Phenolics-Based UV-Filters: A Multidisciplinary Journey

“…Such molecules turned out to provide a full coverage of the UV-A and UV-B regions of the electromagnetic spectrum, by increasing the conjugation throughout a longer backbone. It is noteworthy to mention that the free phenol can also be functionalized in order to be grafted onto materials—providing them with anti-UV properties ( Peyrot et al, 2020a ; Joram Mendoza et al, 2020 ; Mendoza et al, 2021a ; Mendoza et al, 2021b )—or even be used for polymerization to directly provide anti-UV materials ( Sasiwilaskorn et al, 2008 ). As previously mentioned, an increased steric hinderance on the β position is a key factor to improve absorption and stability against UV radiation exposure.…”

Nanocarriers as Active Ingredients Enhancers in the Cosmetic Industry—The European and North America Regulation Challenges

“…Nanoemulsions Astaxanthin Anti-ageing [187] Dendrimers Resveratrol Anti-ageing [135] Solid lipid nanoparticles Nanostructured lipid carriers Nanoemulsion Lutein Anti-ageing [188] Nanostructured lipid carriers Finasteride Anti-alopecia [189] Nanoemulsions Minoxidil Anti-alopecia [190] Nanocapsules Hinokitiol Anti-alopecia [191] Lipid nanoparticles Hinokitiol Anti-alopecia [192] SLN-Silica particles Octyl methoxycinnamate Sunscreen [193] Nanostructured lipid carriers Quercetin Sunscreen [104] Gold nanoparticles Snail slime Sunscreen [194] Cellulose nanocrystals Diethyl sinapate Sunscreen [195] Nanoemulsions Sunflower oil Sunscreen [77] Nanocapsules Octyl dimethyl para-aminobenzoic acid Sunscreen [119] Liposomes Nanostructured lipid carriers Solid lipid nanoparticles Avobenzone Omega-3 UV blocking sunscreen [196] Cubosomes Erythromycin Anti-acne [136] Microemulsions Curcumin Anti-acne [197] Microemulsions Thai basil oils Anti-acne [198] Liposomes Lauric acid Anti-acne [199] Keratin: Zein nanoparticles Fragrances (linalool and menthol) Hair cosmetic [200]…”