Enhancing Formulation Stability: A Comparative Study of Ascorbic Acid and Ascorbyl Palmitate as Antioxidants in Nanoemulsions of Natural Products

Article Article scientifique Article Enhancing Formulation Stability: A Comparative Study of Ascorbic Acid and Ascorbyl Palmitate as Antioxidants in Nanoemulsions of Natural Products eng 2025-06-04 author Majchrzak Oliwia Barbara 0009-0002-4532-1134 938120 Section des sciences pharmaceutiques (FARMA) author Makiej Aleksandra author Lopes Silva Carolina 939521 author Jordan Olivier 0000-0003-3752-2198 133859 Section des sciences pharmaceutiques (FARMA) author Borchard Gerrit 0000-0001-6268-2586 635281 Section des sciences pharmaceutiques (FARMA) author Marcinkowska Agnieszka author Platkiewicz Julia author Zgola-Grzeskowiak Agnieszka author Kaczorek Ewa author Smulek Wojciech 12306-12313 10.1021/acsanm.5c02114 Ascorbic acid is a well-known antioxidant widely used in cosmetics, pharmaceuticals, and food products. However, its hydrophilic nature limits its effectiveness to the aqueous phase, making it challenging to harness its full potential in complex formulations. To overcome these limitations, lipophilic derivatives such as ascorbyl palmitate have been developed to extend its antioxidant activity beyond monophasic systems. Despite the known antioxidant benefits of vitamin C, only a limited number of studies has directly compared the impact of its hydrophilic and lipophilic forms on emulsion stability and oxidative resistance. This study investigates the effects of hydrophilic (ascorbic acid, AA) and lipophilic (ascorbyl palmitate, AP) forms of vitamin C on the oxidative stability, physicochemical properties, and cytocompatibility of oil-in-water nanoemulsions of natural products designed for topical applications. Nanoemulsions were formulated with poppyseed oil as the oil phase, incorporating standardized concentrations of AA or AP. The emulsions were characterized for droplet size (∼200 nm, PDI < 0.3), zeta potential (below −30 mV), Newtonian rheological behavior, antioxidant activity, and thermal stability. Additionally, <i>in vitro</i> cytocompatibility was assessed using THP-1 monocytes to evaluate immunogenic responses. Our findings demonstrate that the antioxidative potency of ascorbic acid exceeds that of ascorbyl palmitate when assessed using the DPPH assay. This study highlights the importance of carefully controlling formulation parameters to maintain the beneficial properties of natural oils. Furthermore, it shows that both antioxidant forms are suitable for the topical application of the poppy seed oil-based nanoemulsion. Ascorbic acid Ascorbyl palmitate Nanoemulsion Lipophilic derivative Bioactive compound Drug delivery Nanocharacterization Dewey 615 31 Section des sciences pharmaceutiques 17 false 879 Biopharmacie ACS Applied Nano Materials 8 23 c33ab263-e9cb-448c-8da7-4572281aee8d Article (Published version) Public enhancing-formulation-stability-a-c.pdf 4204677 application/pdf CC BY-4.0 1281924d109b1faf3c30b750ca7193971b2efaf9b534ec1f81ca2496712ef0b5 Vignette Public images_large_an5c02114_0008.jpeg 259428 image/png openAccess Faculté des sciences / Section des sciences pharmaceutiques

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Enhancing Formulation Stability: A Comparative Study of Ascorbic Acid and Ascorbyl Palmitate as Antioxidants in Nanoemulsions of Natural Products	ACS Applied Nano Materials			2025	27	69

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Lopes Silva, Carolina