GLYCERYL STEARATE

Innovation is considered a determining factor in the highly competitive environment of the cosmetic industry to introduce products while creating new needs. The goal of the study consisted of developing a highly natural and minimalist emulsion with sensorially pleasant skin application highlighted by an innovative ingredient based on a Ca 2+ double cone vector system. The desired product characteristics include a creamy, white texture that is not too greasy or excessively whitening, with rapid skin penetration to facilitate its use for skin treatment. To determine the ideal composition of the emulsion, a design of experiment (DoE) based strategy was applied in two steps: a screening step followed by optimisation. The screening step aimed to identify the key potential ingredients and process parameters that have a significant impact on the rheological and textural properties of the emulsion. The optimisation step provided the final emulsion formula with the desired physicochemical parameters and sensory characteristics. After rheological and sensory analysis, the screening of different ingredients revealed that the combination of 0.8% xanthan gum as the thickening agent (TA), glyceryl stearate citrate and polyglyceryl-3 stearate and hydrogenated lecithin as surfactant S1, and 1% of a mixture of C15-19 alkane (plant-based and renewable) - coco-caprylate/caprate as the sensory agent (SA1) provided the best sensorial qualities for the emulsion. The study demonstrated that the deflocculating rod met one of optimisation's target criteria through its process effect. Based on DoE, the final formulation resulted in a visually white formulation that was neither too greasy nor excessively whitening and highly penetrative of the skin, offering a comfortable face or body cream application for adults and children. L'innovation est considérée comme un facteur déterminant dans l'environnement hautement concurrentiel de l'industrie cosmétique, permettant d'introduire de nouveaux produits tout en créant de nouveaux besoins. L'objectif de cette étude est de développer une émulsion très naturelle et minimaliste, offrant une application sensorielle agréable sur la peau, mise en valeur par un ingrédient innovant basé sur un système vecteur en double cône de Ca 2+ . Les caractéristiques recherchées pour le produit incluent une texture crémeuse et blanche, pas trop grasse, ni excessivement blanchissante, avec une pénétration cutanée rapide facilitant son utilisation dans les soins de la peau. MÉTHODES: Pour déterminer la composition idéale de l'émulsion, une stratégie basée sur la méthodologie du plan d'expériences (Design of Experiment, DoE) a été appliquée en deux étapes: une étape de criblage suivie d'une optimisation. L'étape de criblage visait à identifier les principaux ingrédients potentiels et les paramètres du procédé ayant un impact significatif sur les propriétés rhéologiques et texturales de l'émulsion. L'étape d'optimisation a permis d'obtenir la formule finale de l'émulsion avec les paramètres physico‐chimiques et les caractéristiques sensorielles souhaités. RÉSULTATS: Après les analyses rhéologiques et sensorielles, le criblage des différents ingrédients a révélé que la combinaison de 0,8 % de gomme xanthane comme agent épaississant (TA) (glycéryl stéarate citrate (et) polyglycéryl‐3 stéarate (et) lécithine hydrogénée) comme tensioactif S1, et 1 % d'un mélange d'alcane C15‐19 (d'origine végétale et renouvelable) ‐ coco‐caprylate/caprate comme agent sensoriel (SA1) apportait les meilleures qualités sensorielles à l'émulsion. L'&#

Traditionally, cosmetic emulsions have been developed using trial-and-error approaches, which can be ineffective and time-consuming. This study employed a Quality by Design approach to determine how formulation ingredients impact the physical stability of a sustainable sunscreen. A 2 3 full factorial design assessed the effects of the concentrations of polyglyceryl-2 stearate, glyceryl stearate, stearyl alcohol (self-emulsifier), brassica glycerides (co-emulsifier), and xanthan gum (gelling agent) on the apparent viscosity and instability index of the emulsified vehicle. Another 2 3 full factorial design evaluated the effects of the concentration of zinc oxide, titanium dioxide, and phytic acid on the instability index of the sustainable sunscreen formulation. The instability index of the emulsified vehicle was influenced by self-emulsifier and co-emulsifier concentrations. In contrast, its apparent viscosity was influenced by self-emulsifier and gelling agent concentrations, and by interactions among self-emulsifier, co-emulsifier, and gelling agent. The instability index of the sunscreen formulation was mainly influenced by zinc oxide and phytic acid concentrations. Robust mathematical models were developed and used to predict the optimal compositions of the emulsified vehicle and sunscreen formulation within the experimental domains. The optimal compositions predicted by the mathematical models developed were 8% self-emulsifier, 3% co-emulsifier, and 0.3% gelling agent for the emulsified vehicle, and 6.3% zinc oxide, 2% titanium dioxide, and 1% phytic acid for the sunscreen formulation. These optimized formulations met the Quality Target Product Profiles, ensuring appropriate physical stability, rheological performance, antioxidant properties, and the desired SPF, water resistance, and UVA-PF characteristics.

The development of an optimal material design is crucial for rice bran wax (RBW) to achieve significant advancements in value-added byproducts. In this study, emulsifier-free, submicron-sized, monodisperse RBW particles were prepared via melt emulsification using a combination of a high-HLB emulsifier-decaglycerin stearate or Tween 20-and a low-HLB emulsifier-glyceryl stearate or Span 20. High dispersibility was achieved due to the zeta-potential generated by the surrounding surfactants, resulting in monodispersed submicron-sized RBW particles. Surface cleaning with ethanol effectively removed surface-adsorbed emulsifiers, yielding emulsion-free RBW particles. Due to the hydrophobic nature of the wax particles, high solvent repellencies were observed, along with the formation of colloidal assemblies such as liquid marbles and W/O Pickering emulsions using cosmetics-applicable liquids. Based on X-ray diffraction analysis and differential scanning calorimetry, RBW was identified as a promising candidate for emulsifier-free submicron-sized particles due to its high crystallinity, which facilitates the effective elimination of emulsifiers.

Pseudohypertriglyceridemia is an overestimation of serum triglyceride levels, potentially leading to an inaccurate diagnosis of hypertriglyceridemia. This can result from hyperglycerolemia, which interferes with enzymatic measurement methods. Hyperglycerolemia may arise from drugs or genetic glycerol kinase defects. We present a case of a severely burned patient with very high triglyceride levels (up to 5696 mg/dL) that was resistant to lipid-lowering treatment, identified during the work up for pancreatitis associated with elevated lipase levels. Despite the very high triglyceride levels reported in the laboratory results, the standing plasma showed clear plasma, with no significant peak of pre-beta lipoprotein observed on serum lipoprotein electrophoresis. Serum apolipoprotein B levels were low, and urine triglyceride levels were high. This case confirms that very high serum glycerol levels caused the false elevations of triglyceride and lipase levels, resulting from hyperglycerolemia induced by the massive topical application of silver sulfadiazine cream (containing glycerine and glyceryl stearate) to the severely burned wound, which interfered with the laboratory assays. Triglyceride and lipase levels dramatically decreased after reducing the dose of silver sulfadiazine cream. No genetic defects related to glycerol kinase deficiency were identified.

The Expert Panel for Cosmetic Ingredient Safety reviewed newly available studies since their original assessment in 2002, along with updated information regarding product types and concentrations of use, and confirmed that these 17 glyceryl diesters are safe as cosmetic ingredients in the practices of use and concentration as described in this report.

Modified Leeming and Notman agar medium (mLNA) has been widely utilized to grow lipophilic fungi belonging to the genus Malassezia. We developed a new artificial-sebum-containing mLNA to obtain higher yields of Malassezia species. The olive oil in mLNA was replaced with an artificial sebum composed of triglyceride (triolein), diglyceride (glyceryl distearate), fatty acids (palmitic acid, myristic acid, pentadecanoic acid, and oleic acid), and squalene. Furthermore, the Tween 60 was replaced with self-emulsifying glyceryl stearate. Nine human-associated Malassezia species grew well on the artificial-sebum-containing mLNA, and the most predominant fungus on human skin, Malassezia restricta, exhibited double wet cell weight in artificial sebum-containing mLNA compared to wet cell weight in standard mLNA.

A sunscreen should form a stable and homogeneous film over the skin surface, which can improve its photoprotective activity and avoid adverse effects. For this purpose, the definition of the appropriate vehicle is of fundamental importance since emulsifying agents are known to directly influence the stability, sensorial properties and surface tension of sunscreens, modulating their film-forming performance. In this context, the objective of the present study was to systematically develop formulations with UVB/UVA protection and evaluate the effect of wax concentration on the rheological behaviour. A 2-level full factorial design was applied for the development of four formulations. Two categorical factors were evaluated, glyceryl stearate plus PEG-75 stearate (Wax 1) and methyl glucose sesquistearate (Wax 2). Rheological behaviour was determined in triplicate and rheograms were analysed using the Ostwald model. Rheological parameters were correlated by the Spearman rank correlation test and effects were evaluated by Pareto chart and surface response methodology (SRM). It was possible to identify the pseudoplastic and thixotropic behaviour of all formulations exhibiting a thinning effect on higher shear stress. Factorial analysis showed that both waxes significantly influenced consistency and thixotropic behaviour. The effect of Wax 2 concentration in thixotropy was positive and of higher magnitude and a synergistic effect was also observed. Spearman correlation coefficient of consistency index and apparent viscosity was significantly strong and positive. Finally, factorial analysis allowed the determination of the effects of waxes on the rheological parameters of the formulations. A quantitative relationship between wax concentration and significant responses was established, permitting the prediction of desirable rheological properties for improved sunscreen efficacy.

The main aims of the present study were to formulate an anti-age cream based on vegetal ingredients and ferulic acid and to evaluate the physical characteristics and the efficacy of the cream. The active ingredients were Centella asiatica oil, Spilanthes acmella oil, Zingiber officinale extract and ferulic acid. Formulation 1 (F1) was prepared using glyceryl stearate and Ceteareth-25® as emulsifiers and Formulation 2 (F2) using glyceryl stearate and potassium cetyl phosphate, all other ingredients remaining the same. The physical characterization of the creams was performed and the following parameters were analyzed: viscosity, oil droplet size, polydispersity index; also, texture analysis was performed. The anti-aging effect of the F2 was evaluated by assessing the cutaneous density before and after cream application using DUB-cutis® scanner. The mean diameter of oil drops was 10.26±4.72 mm (F1) and 22.72±7.93 mm (F2) and the polydispersity index was 35.4% and 45.7%, respectively. The mean values for consistency were 594.7±10.3 g (F1) and 300.5±14.5 g (F2), the average values for adhesion were 15.61±0.8 mJ (F1) and 22.25±4.3 mJ (F2), for firmness were 51.2±0.8 g (F1) and 30.3±4.3 g (F2) and the spreadability had values between 72.63 mm2 (F1) and 73.3 mm2 (F2). In vivo study revealed that the mean values of the cutaneous density increased from 9.21±1.39 % to 12.50±1.44 % after 8 weeks of cream application. The herbal ingredients incorporated in the O/W cream base for the antioxidant activity and anti-wrinkle effect, induced changes of the cutaneous density, an important parameter which quantifies the regeneration process of the skin. An anti-age cream containing herbal active ingredients and ferulic acid with appropriate physical characteristics was obtained. In vivo study of clinical efficacy revealed a positive effect on skin density, which increased after 8 weeks of cream application.

Allergic contact dermatitis commonly occurs on the face. Facial cleansing wipes may be an underrecognized source of allergens. The aim of this study was to determine the frequency of potentially allergenic ingredients in facial wet wipes. Ingredient lists from name brand and generic facial wipes from 4 large retailers were analyzed. In the 178 facial wipes examined, a total of 485 ingredients were identified (average, 16.7 ingredients per wipe). Excluding botanicals, the top 15 potentially allergenic ingredients were glycerin (64.0%), fragrance (63.5%), phenoxyethanol (53.9%), citric acid (51.1%), disodium EDTA (44.4%), sorbic acid derivatives (39.3%), tocopherol derivatives (38.8%), polyethylene glycol derivatives (32.6%), glyceryl stearate (31.5%), sodium citrate (29.8%), glucosides (27.5%), cetearyl alcohol (25.8%), propylene glycol (25.3%), sodium benzoate (24.2%), and ceteareth-20 (23.6%)/parabens (23.6%). Of note, methylisothiazolinone (2.2%) and methylchloroisothiazolinone (1.1%) were uncommon. The top potential allergens of botanical origin included Aloe barbadensis (41.0%), chamomile extracts (27.0%), tea extracts (21.3%), Cucumis sativus (20.2%), and Hamamelis virginiana (10.7%). Many potential allergens are present in facial wet wipes, including fragrances, preservatives, botanicals, glucosides, and propylene glycol.

Compared with ordinary emulsified cosmetics, liquid crystal emulsified cosmetics have obvious advantages. In this paper, an ultra-micro liquid crystal (ULC) emulsion with particle size less than 4 μm was successfully synthesized using a simple oil-in-water emulsification method, and large liquid crystal (LLC) and non-liquid crystal (NLC) emulsions were also prepared as controls. Three kinds of emulsions were examined by polarizing microscopy, X-ray diffraction (XRD), small-angle X-ray scattering (SAXS) and cryo-transmission electron microscopy (cryo-TEM). Rheological tests, in vivo experiments, reconstructed Raman maps tracking selected markers and thermogravimetric (TG) results showed that the ULC emulsion expressed excellent viscoelasticity, long-term moisturizing property with barrier function and better selective delivery of active substances compared with LLC and NLC emulsions. Molecular dynamics simulation on the ULC system and deuterium order parameter plots respectively indicated that GYY (glyceryl stearate citrate) showed a tendency to form a stable structure by reducing the total interaction energy and enhancing system lamellar ordering. This work not only demonstrates the great potential of ultra-micro liquid crystals in for commercial applications in cosmetics but also offers a deeper understanding of the intrinsic properties and growth mechanisms of ultra-micro liquid crystals at the microscopic level.

Double hydrophilic, random, hyperbranched copolymers were synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization of oligo(ethylene glycol) methyl ether methacrylate (OEGMA) and 2-(dimethylamino)ethyl methacrylate (DMAEMA) utilizing ethylene glycol dimethacrylate (EGDMA) as the branching agent. The resulting copolymers were characterized in terms of their molecular weight and dispersity using size exclusion chromatography (SEC), and their chemical structure was confirmed using FT-IR and 1 H-NMR spectroscopy techniques. The choice of the two hydrophilic blocks and the design of the macromolecular structure allowed the formation of self-assembled nanoparticles, partially due to the pH-responsive character of the DMAEMA segments and their interaction with -COOH end groups remaining from the chain transfer agent. The copolymers showed pH-responsive properties, mainly due to the protonation-deprotonation equilibria of the DMAEMA segments. Subsequently, a nanoscopic polymer-lipid (lipomer) mixed system was formulated by complexing the synthesized copolymers with cosmetic amphiphilic emulsifiers, specifically glyceryl stearate (GS) and glyceryl stearate citrate (GSC). This study aims to show that developing lipid-polymer hybrid nanoparticles can effectively address the limitations of both liposomes and polymeric nanoparticles. The effects of varying the ionic strength and pH on stimuli-sensitive polymeric and mixed polymer-lipid nanostructures were thoroughly investigated. To achieve this, the structural properties of the hybrid nanoparticles were comprehensively characterized using physicochemical techniques providing insights into their size distribution and stability.

Glyceryl stearate and cassava starch (CS) composites were prepared by an esterification process. Formulations containing starch at various concentrations were prepared, being 1, 1.5, 3, 5, 10, 15, 20, and 30 % by weight, respectively. The characteristics of pH, moisture content, FTIR, melting point, latent heat, thermal energy storage, and specific heat capacity of composites were elucidated. The optimal formulation contained 1 % w/w CS, this indicated that the composite was able to maintain its temperature for 9.4 ± 0.5 min, with a melting temperature of 51.9 ± 0.3 °C, solidification temperature of 36.1 ± 1.6 °C, latent heat of fusion of 120 ± 10 J/g, and latent heat of solidification of 126 ± 3 J/g, and specific heat capacity of 2.6 ± 0.2 J/g.K. New bonds were formed in the composite structure of glyceryl stearate and CS at these levels. The composite had a pH that was safe for contact with human skin and a moisture content that could be kept stable for a prolonged time. The innovation and the advantages of a composite materials: 1. The main components are derived from natural materials. 2. Costs effective 3. Sustainability 4. Safety, and 5. Efficacy. Therefore, composites have a high potential as are replacement for paraffin wax bath therapy.