Improving the stability of retinol: Overcoming obstacles through solid lipid particle technology.

Summary: Abstract Body: Retinol, while powerful in anti-aging skincare, is known for its instability due to oxidation, its poor bioavailability and its potential to cause skin irritation. To tackle these challenges, we developed an innovative specific Solid Lipid Particle(SLP) technology. SLPs offer distinct advantages over other particle types by effectively protecting active ingredients while facilitating the release of the encapsulated molecules. To prove the efficacy of this specific SLP technology regarding retinol, we evaluated its stability formulated in a cream in a real-life study (product opened every day, for 4 months) versus a market benchmark(closely related particle technology). The bioavailability of encapsulated retinol was evaluated through the measurement of collagen I (immunostaining) on skin explants vs non-encapsulated retinol. Additionally, irritation potential was monitored by measuring pro-inflammatory response (IL-8 by Elisa) on fibroblasts. After 4 months of real-life use, the SLP formulation achieved an 83% retinol retention rate, significantly surpassing the 46% of the benchmark. Retinol is also bioavailable as collagen I was increased by 43% after SLP application, matching the level of non-encapsulated retinol. Furthermore, retinol irritation potential was avoided with the SLP technology. No stimulation of Il-8 secretion was observed with encapsulated retinol whereas the non-encapsulated retinol (free Retinol and empty solid lipid particles in solution) significantly induced IL-8 by 47% vs untreated control. In conclusion, the SLP encapsulation technology effectively addresses the main drawbacks of retinol by enhancing its stability, bioavailability, and minimizing skin irritation. This ultimate encapsulation solution enables the use of retinol without any formulation and packaging constraints. This advancement better addresses consumer demand for effective retinol formulations that provide visible anti-aging benefits. Philip Ludwig¹, Isabelle Bonnet², Ginger Zhang³, Corinne Thiel⁴, Chiung-Yueh Hsu⁴, Valérie André² 1. BASF Corp Tarrytown, Tarrytown, NY, United States. 2. BASF Beauty Care Solutions France SAS, Lyon, Auvergne-Rhône-Alpes , France. 3. BASF Advanced Chemicals, Shangai, China. 4. BASF Beauty Care Solutions SAS, Essey-lès-Nancy, Alsace-Champagne-Ardenne-Lorraine, France. Stem Cell Biology, Tissue Regeneration and Wound Healing