Stabilization of ferulic acid in topical gel formulation via nanoencapsulation and pH optimization

Abstract

Ferulic acid is a potent anti-oxidant with scientifically proven skin care efficacies. However, instability of this active in the skin care products restricted its wide application in beauty and skin care industries. This study aimed to stabilize ferulic acid in topical hydrogel formulation via nanoencapsulation technique. ferulic acid loaded nanocapsules were prepared via high pressure homogenization method and physicochemically characterized. Mean particle size of ferulic acid loaded nanocapsules was < 300 nm. TEM and SEM images exhibited spherical particles with smooth surface. DSC and XRD results indicated that ferulic acid was completely dissolved in the lipid matrix of the nanocapsules and remained in amorphous form. Two types of hydrogel formulations containing ferulic acid loaded nanocapsules were prepared: Gel A with pH higher and Gel B with pH lower than pKa of ferulic acid. cross-polarized microscopic image of the gel formulations did not show presence of any un-encapsulated and un-dissolved crystal. Gel B showed slower and controlled release of ferulic acid than Gel A. Ferulic acid permeation through skin mimic from the gel formulation demonstrated controlled permeation. Color stability of the gel and chemical stability of ferulic acid were very good in Gel B, while poor in Gel A (although significantly better than the gel with un-encapsulated ferulic acid). The result clearly indicates that together with nanoencapsulation, low pH (less than pKa of ferulic acid) of the hydrogel was crucial for both product appearance and chemical stability of ferulic acid. In fact, it has been proved that skin care product with low pH is good for skin as it can maintain skin homeostasis and microbiome. Furthermore, the permeation result suggests that ferulic acid may penetrate into deep skin layers and at the same time avoid systemic circulation. Overall, this low pH hydrogel formulation containing nanoencapsulated ferulic acid demonstrates great promise for commercialization. Antioxidants are among the most abundant actives in skin care products, such as anti-aging, anti-pollution products. Antioxidants are used to prevent/delay skin aging caused by environmental aggressors like pollution, infrared (IR) radiation, and ultraviolet (UV) rays 1-4. However, antioxidants are often associated with stability challenges when incorporated in the skin care products 3,5. Antioxidants may partially or fully degrade into inactive forms during product shelf-life 6-8. The degradation usually accelerates at high temperature (e.g., 40 °C) and under light (e.g., UV and fluorescent) 5,7,8. This instability of the antioxidant actives ultimately reduces product's efficacy and most of the time leads to product color change during storage 9,10. Hence, consumer acceptance of the products also decreases. In recent years, there is a huge interest on naturally occurring active ingredients for skin care products. One of the potent natural antioxidant is ferulic acid which is 4-hydroxy-3-methoxycinnamic acid 11. Ferulic acid is a phytochemical w...

Rapid determination of L‐ascorbic acid content in vitamin C serums by ultra‐high‐performance liquid chromatography–tandem mass spectrometry

“…For this reason, one strategy that can be applied to overcome this limitation is the addition of preservatives in the formulation [12]. According to the product marketing materials of the samples analysed in this study, many antioxidant additives are added to the vitamin C serum, to improve the stability of the product [4], including vitamin E (α‐tocopherol), phloretin, ferulic acid, neohesperidin dihydrochalcone and tocopheryl acetate (Table 1). In addition, samples AH1, AH3 and CL2 present in their composition plant extracts with antioxidant characteristics [36–38], such as flavonoids of Ginkgo biloba leaf extract, pinus pinaster bark/bud extract and Salvia officinalis L. leaf extract, respectively.…”

“…Skin is an external organ that is often exposed to environmental factors such as ultraviolet (UV) radiation, smoke and air pollution, which accelerate skin ageing [1]. A recommended technique to protect and treat the human skin against the action of these environmental aggressors is the topical administration of moisturizers [2] and facial serum [3] composed of antioxidants such as ferulic acid [4], L-ascorbic acid (L-AA, vitamin C) [3,5] or melatonin [6].…”

Design and Synthesis of Novel Peptides to Protect Ferulic Acid against Ultraviolet Radiation Based on Domain Site IIA of Bovine Serum Albumin

“…It was shown that almost half of the FA was destroyed in this period. Because FA is unstable under neutral/alkaline conditions, UVA depredates FA easily [ 14 , 21 ]. On maintaining the UVA irradiation up to 12 h later, the solution became stable and its RR value held at 29.6%.…”

Gamma oryzanol niosomal gel for skin cancer: formulation and optimization using quality by design (QbD) approach

“…The neutral pH value indicates that the niosomal gel of OZ can avoid any possible skin irritation rendering the niosomal formulation to be safe. Furthermore, pH optimization can also improve the stabilization of active pharmaceutical ingredients in gel formulation for topical use (Das and Wong 2020). The torque obtained was more than 85%.…”