The development and validation of 3D skin models represent pivotal advancements in dermatological research and cosmetic testing. These models offer a viable and ethical alternative to traditional animal testing, which faces increasing regulatory and ethical scrutiny. This article provides a comprehensive review of the history, development, and specific applications of 3D skin models within the cosmetic industry. The transition from 2D cell cultures to advanced 3D constructs has mitigated many limitations inherent in earlier models, such as the inability to replicate the complex architecture and interactions of human skin. Innovations, including bioprinting, personalized skin models, and integration with microfluidics, have enhanced the physiological relevance and application scope of these models. Despite these advancements, 3D skin models continue to face challenges related to their complexity, variability, high production costs, and ability to simulate long-term and environmental conditions. This review underscores the need for ongoing innovation and collaboration to address these challenges and to expand the utility of 3D skin models in cosmetics and beyond. Future directions include enhancing model complexity by incorporating immune components, vascularization, and advanced scaffold materials, by developing standardized protocols and stringent quality control measures, and by leveraging big data analytics and machine learning to improve the predictive power and utility of 3D skin models in both research and regulatory settings.
In this study, the validity of a questionnaire, combined with a stinging test, was evaluated to identify sensitive skin among Koreans and to determine its effectiveness in distinguishing individuals who had sensitive skin with objective skin irritation. A total of 113 female participants were assessed using a sensitive skin questionnaire, a lactic acid stinging test, and sodium lauryl sulfate patch testing. Results showed that the questionnaire had high reliability. A receiver operating characteristic analysis indicated that the questionnaire exhibited strong discriminative ability in identifying sensitive skin. Correlation analysis with sodium lauryl sulfate patch testing revealed that the combined use of the questionnaire and stinging test provided the highest correlation for sensitive skin detection. Therefore, this combination can effectively identify sensitive skin with objective skin irritation and provide valuable insights into the development and marketing of cosmetic products targeting consumers with sensitive skin.
We aimed to apply an oleogel emulsion formulation using ceramide and sucrose stearate as mixed gelators in the development of sunscreen stick products. Changes in gel stability, appearance, hardness, spreadability, and in vitro SPF value were examined in varying compositions of the sunscreen sticks. The incorporation of sodium carboxymethyl cellulose or titanium dioxide powder into the oleogel emulsion formulation was found to be crucial for maintaining a stable gel state. Increasing the amount of water and ceramide enhances hardness and SPF value but reduces gloss. Sunscreen sticks formulated with the oleogel emulsion exhibited greater gloss, lower hardness, improved spreadability, and elevated SPF values compared to those made with beeswax or polyethylene. The bound water ratio in the oleogel emulsion formulation was determined to be approximately 3.83%.
Surfactants in cosmetic formulations can irritate the eye and cause discomfort when the eye is exposed to these formulations, especially for infant formulations. Sensitive in vitro models to predict in vivo eye irritation potential are beneficial for the development of consumer-friendly formulations. In this study, the effects of selected surfactant formulations (e.g., sodium methyl cocoyl taurate and sodium lauroyl glutamate) on the corneal barrier were evaluated using a recently developed EpiCornealTM model in vitro and in a human clinical study. The changes in the corneal barrier function were determined using the electrical conductance of EpiCornealTM to identify the surfactant formulations that would not significantly impact the corneal barrier. The EpiCornealTM results showed that the tested formulations did not significantly affect the corneal barrier. The sodium lauroyl glutamate-based formulations had the least effect on the tissue barrier. The presence of a nonionic capryloyl/caproyl methyl glucamide and cationic hydroxyethyl cellulose (polyquaternium-10) decreased the effects of the sodium methyl cocoyl taurate-based formulations on the epithelial barrier. The in vitro experiments were validated by the human study of the prototype formulations via direct instillation of diluted formulations in human volunteers. The EpiCornealTM conductance model provided quantitative in vitro assessments on potential eye-irritating chemicals and could be an alternative to in vivo testing.
This review will cover sources of human skin for research, the methodology used for separating the epidermis from the dermis, and isolating the stratum corneum. In the development of cosmetic products and ingredients, it is generally necessary to determine the extent of partitioning and penetration from the skin surface. In such studies, it may be useful to be able to separate the epidermis, dermis, and stratum corneum. This separation enables determination of ingredient concentrations in each of these skin sections, and it permits the investigation of the effects of the vehicle formulation on the extent of partitioning. This can also be useful in studies of metabolism, mechanisms of action, and potentially for local or systemic toxicity. The uses of skin, epidermis, and stratum corneum in permeability studies, cell culture, and biochemical studies are also cited. The main separation methods to be discussed are heat separation, suction blister formation, and dispase (a neutral protease) treatment. The overall purpose of this review is to assist investigators, new or established, to venture into the use of ex vivo human skin, epidermis, and/or stratum corneum in their research. The main messages of this review are: human skin is usually obtained by arrangement with local hospitals, biobanks, or through commercial vendors where fresh or frozen human skin is available; each method for separation of epidermis from dermis has its own unique advantages and limitations; and stratum corneum for physical or biochemical studies can be prepared by treatment of epidermis with trypsin.
This study aims to develop a cosmetic hydrogel facial mask designed to enhance skin hydration and elasticity. The optimized formulation was evaluated for its rheological, swelling, and mechanical characteristics, followed by long-term stability testing. Acetylhexapeptide-8, the main bioactive compound in the hydrogel, was quantified using UPLC-HRMS. The neutral pH condition provided the most stable swelling behavior, while diffusion coefficient analysis revealed a non-Fickian (n > 0.5) mechanism. The formulation containing 0.05% acetylhexapeptide-8, identified as the optimal concentration, was selected as the most thermally stable. No organoleptic changes occurred in formulations stored at refrigerated or ambient conditions. The developed hydrogel mask demonstrated significant efficacy in reducing fine lines and wrinkles. Overall, acetylhexapeptide-8-loaded hydrogel masks exhibit strong potential as advanced anti-aging products, offering performance comparable to botulinum toxin
This study investigated the synergistic effects of polyols and raspberry ketone (RK) on antimicrobial activity in oil-water emulsion. The amount/distribution ratio of RK in water phase, with different polyols, 1,3-Propanediol/ 1,3-Butanediol/ 1,2-Pentanediol /1,2-Hexanediol, and four commercially available oils (squalane, silicone oil, caprylic/capric triglyceride, and isononyl isononanoate), was measured by high performance liquid chromatograph. The antimicrobial synergy between RK and polyols was determined via minimum inhibitory concentration and fractional inhibitory concentration, which was also studied in oil-water emulsions. The relative concentrations of RK in water phase of emulsion with squalane and silicone oil were significantly higher, as compared to caprylic/capric triglyceride and isononyl isononanoate. The addition of polyols effectively facilitated the migration of RK into the water phase in all oil-water systems. All the fractional inhibitory concentration values of RK and polyols against Candida albicans were greater than 1, indicating there is no synergistic effect, while RK exhibited a stronger antimicrobial effect with hexanediol and non-polar oils. This study showed the stronger antimicrobial effect is due to the increase of solubility and distribution ratio of RK in the water phase or water-oil interface of emulsion.
Most skin aging signs result from the cumulative effects of environmental stresses and chronological factors, leading to the formation of radical oxygen species and inflammatory mediators. It was shown that crocin endows antioxidant potential against reactive oxygen species and prevents inflammation. Considering that Crocus sativus (saffron) contains a high concentration of crocin, the goal was to develop a new extract of Crocus sativus complying with cosmetic regulation and obtain an efficient cosmetic ingredient on skin inflammation and oxidation to protect skin. Quantification tools (high-performance liquid chromatography (HPLC)/ DAD, spectrophotometry) were used to analyze the presence of crocin, picrocrocin, and polyphenols. The selected extract is obtained from the Crocus sativus stigma sourced from the Ourika valley in Morocco. Light exposure played a crucial role in optimizing the concentration of crocin. The resulting extract is a powdered pure extract that contains a minimum of 20% crocin, with the remaining 80% consisting of polyphenols, carbohydrates, and amino acids that can be easily solubilized in water. The in vitro tests provided good results on antioxidant effects and anti-inflammation effects by protecting against IL-1 stress, UV, and pollutant exposure. In addition, the saffron extract demonstrated pro-migration effect on keratinocytes.
Solid perfume is a cosmetic product that is made from wax, carrier oil, and essential oil and hardens at room temperature. Cacao butter in solid perfume contains vitamin E that provides a moisturizing effect. Essential oils, as fragrances, have aromatherapy effects. To preserve the fragrance, patchouli oil is used as a fixative agent. This study aims to investigate the effect of patchouli oil on physical properties, chemical functional groups, and volatile constituents of solid perfume during five weeks of storage. The solid perfume showed stability in physical properties, and the chemical functional group showed intensity reduction in accordance with the change of volatile constituent after five weeks. The presence of patchouli oil as fixative agent could retain volatile constituents for middle notes and base notes essential oils. Based on Fourier Transform Infra-Red analysis, the solid perfume which comprised high base note concentration was chemically more stable as formulated in the study. However, based on organoleptic tests, the solid perfume still released its fragrance characteristics. This result supported that the solid perfume products in this study were feasible to be used in a long term as a long-lasting cosmetic product.
Cellulose is an emerging new material used in various cosmetic applications, but its common designation as a single International Nomenclature of Cosmetic Ingredients term fails to capture diversity among its many forms. To make informed choices about cellulose usage, a deeper understanding of its characteristics is essential. This study evaluates 10 different ingredients, all labeled with "cellulose" in their International Nomenclature of Cosmetic Ingredients names, to elucidate the relationship between the physical properties of cellulose powders-such as particle size, shape, and absorption profile-and their functional benefits. Testing conducted includes particle size analysis using laser scattering, oil uptake, and soft focus assessment via spectrophotometry, and optical assessment utilizing Biody (R) artificial skin discs. Additionally, in vivo tests on color intensity and sensory perception were performed using a statistically analyzed panel. Results indicate that optical effects are significantly influenced by particle size and shape, with smaller cellulose particles providing immediate soft focus benefits. The primary differences among the 10 celluloses examined stem from their morphological characteristics resulting from their manufacturing processes. This study demonstrates that a "one size fits all" approach is inadequate for cellulose. A comprehensive consideration of its full range of characteristics and production method is necessary to effectively leverage its performance benefits and sustainability.
Keratin plugs, which block pores, are a common issue facing young individuals. Keratin plugs are complex structures composed of multiple layers of proteins and lipids, and their composition varies between individuals. To safely remove keratin plugs, there is a need to develop an index for assessing their solubility. In this study, we focused on the Hansen solubility parameter (HSP) as an indicator of solubility. The HSP is an extension of Hildebrand's solubility parameter and has been utilized in various fields, including pharmaceuticals, petrochemicals, polymers, and particles, as an indicator of substance affinity. However, its application to clarify and improve the solubility of keratin plugs in humans has been insufficiently explored. In this study, we measured and defined the HSP of keratin plugs using Hansen's solubility sphere method. Additionally, we developed a method to predict the solubility of keratin plugs with a high probability (85.7%) based on the HSP distance between keratin plugs and raw materials. Our findings suggest that the HSP can serve as a useful indicator for identifying combinations of raw materials with high solubility for keratin plugs.
Many consumers have become wary of industrially produced cosmetics, and there has been a simultaneous attraction to DIY recipes for hygiene, healthcare, and makeup products. The aim of this work was to study DIY perfume recipes. We collected recipes for DIY products found on social media (blogs, YouTube, Facebook, Pinterest, Instagram, and TikTok) in French and English, then analyzed their composition as well as how practical it is to make them. The aim of this study was to evaluate the relevance of DIY perfumes and to find out if these recipes could be used to obtain high-quality, safe products. We compiled and studied 143 recipes. These were primarily hydroalcoholic solutions, with concentrations of essential oils more like those of Eau de Cologne than of actual perfume. Among the recipes, we also found examples of oil solutions, solid products, and aqueous solutions. The results obtained from these recipes were quite different from commercial formulas created by professional perfumers. The homemade 'perfumes' had very poor stability after three months and the aqueous solutions were not immediately homogeneous, as additions of solubilizers were never suggested. These recipes had many common characteristics, such as imprecise dosages and no antioxidants. The latter is a major problem for the preservation of the products once made and could lead to the formation of hydroperoxides. The recipes studied cannot compete with the perfumes available on the market in terms of results and lack stability in formulation. These DIY perfumes do not comply with International Fragrance Association recommendations and should therefore be strongly discouraged.
This study investigates the clinical efficacy of a sulfate-free shampoo formulated with Platycladus orientalis leaf extract for the prevention of hair loss. A total of 70 participants were enrolled in a randomized, doubleblind, placebo-controlled trial, with 66 completing the study. Over a 12-week period, participants applied the shampoo thrice-weekly, and hair shedding was assessed using standardized combing techniques, while local hair density was measured through dermatoscope imaging. The experimental group showed a significant reduction in hair loss at 4, 8, and 12 weeks compared to the baseline (p < 0.001). Despite the absence of statistically significant increase in local hair density in the experimental group, it remained stable, whereas the control group experienced a notable decline (p < 0.01). Consumer satisfaction surveys revealed higher satisfaction rates in the experimental group, particularly for hair loss prevention and scalp oil control. This study demonstrates that the sulfate-free shampoo is effective in reducing hair shedding and maintaining scalp health. Further research is warranted to explore the specific mechanisms of action of Platycladus orientalis anti-hair loss formulations.
Shampoos are the most used form of hair treatment. They are products primarily designed to clean the hair and scalp. There are many shampoo formulas in Algeria, available from different production units. This study aimed to determine whether these formulas complied with both international and Algerian standard specifications, and to what extent these specifications were applied. Two shampoo formulas were developed based on avocado oil at doses of 0.3 and 0.2%. We carried out sensory, physicochemical, microbiological, and rheological controls of the finished product, which gave results within conformity of current standards. To confirm the looping shampoo activity, 24 women with hair types suitable for our product applied the shampoos. 12 of them used the shampoo made with sulfate (0.3% avocado oil), and they noticed curling activity. However, the other 12 women who used the shampoo without sulfate noticed dryness on the ends of their hair. In conclusion, both shampoos (with sulfate and without sulfate) can be recommended to give curls to the hair.
Compared to other body parts, psoriatic lesions on scalp have resistance to treatments and are more prone to recurrence. This study aims to investigate if the scalp psoriasis has special disease phenotype and to further identify the biomarkers and their correlation with infiltrated immune cells. We surveyed patients to map scalp psoriasis incidence and treatment response, then mined GEO datasets for differential genes versus non-scalp psoriasis. Enrichment, PPI, and immune-cell deconvolution (CIBERSORT) identified pathways and infiltrates; LASSO selected biomarkers and AUC tested discrimination. Results show that scalp psoriasis had a severe disease phenotype and poor treatment response. The activated memory CD4+ T cells, M2 macrophages, and memory B cells may act as critical cell types and S100A12 may be a potential treatment target for scalp psoriasis. In conclusion, scalp psoriasis may have more severe disease phenotypes and may be related to genetic and immune mechanisms.
Current technologies rely on consumer studies to evaluate the rinsing profiles of bodywash products. Most objective methods either measure the skin friction at the static state or are too complicated to be widely applied. An evaluation system has been developed to assess dynamic skin friction during the rinsing stage to predict the sensory feel of bodywash on the skin. In the present study, three commercial bodywashes were selected and measured based on the level of slipperiness and on duration time. The data obtained was compared to a well-trained sensory panel (10 panelists). The results showed that the skin friction of soap-based bodywash increased rapidly to the highest value within the shortest time, while surfactant-based bodywash showed the lowest value with the longest time while washing with tap water. While washing with deionized water, no significant difference was observed between soap-based and surfactant-based bodywashes. The results correlate well with panel grading (Spearman's rho= 0.69, p < 0.001). By adding hydroxypropyl methylcellulose to a soap-based bodywash, not only was the skin irritation reduced, but so was the squeaky feel, and skin felt smoother after washing.
The study aimed to compare the effectiveness and safety of polylactic acid (PLA) and hyaluronic acid (HA) in enhancing double-fold eyelids through minimally invasive procedures. A randomized clinical trial was conducted involving 80 patients seeking double-fold eyelid enhancement. Participants were randomly assigned to either the PLA group or the HA group. Clinical outcomes were assessed using objective measurements of eyelid size, patient-reported satisfaction, and the incidence of adverse events at baseline, and then at one-, three-, and six-months post-procedure. Both PLA and HA effectively increased the size of double-fold eyelids. The PLA group showed more prolonged results, maintaining the effects for up to six months, while the HA effect significantly diminished after three months (p < 0.05) The incidence of adverse events was significantly higher in the PLA group, with 20% of patients reporting mild complications, compared to nearly 10% in the HA group (p < 0.05) The study concluded that the choice between PLA and HA should be guided by individual patient preferences, including longevity, aesthetic goals, and tolerance for potential side effects.
Synopsis Hair damage, caused by factors such as chemical treatments, environmental stressors, and mechanical forces, is primarily due to the disruption of disulfide bonds within keratin fibrils. Among the different solutions for hair repair, consumers are increasingly demanding natural, effective products. To address this, a novel hair bond multiplier, consisting of silica particles decorated with cysteines (Si-Cys-complex), has been developed. This product stabilizes and delivers cysteine to the hair shaft, facilitating the restoration of disulfide bonds. The successful cysteine conjugation to the silica particles, as well as their size and morphology, were proved through dynamic light scattering, electron microscopy, energy dispersive spectroscopy, and thermogravimetric analysis. Ex vivo and in vivo studies demonstrated that Si-Cys-complex effectively penetrates the hair shaft, repairs damaged keratin fibers, reduces cuticle damage maintaining a smoother hair surface, and exhibits excellent water resistance, outperforming synthetic benchmarks in maintaining hair integrity. Additionally, consumer and expert evaluations confirmed the product's efficacy in enhancing shine, softness, combing ability, and color vibrancy, with effects persisting after 28 days. Si-Cys-complex represents a robust, natural alternative to synthetic bond multipliers, offering a multifunctional hair care solution that aligns with consumer preferences while delivering superior performance in repairing and protecting damaged hair.
Lipstick has been a distinctive piece of culture and society for centuries since its invention. Developments in formulation technology have made lipstick more accessible and a part of people's daily routines. More recently, consumers have become interested in how their products are made. Over the last several years, the demand for biobased ingredients has significantly increased in the cosmetic industry. Transfer resistance is another feature that is in high demand. Polymers used to prevent transfer are often made from silicones, which are not considered biobased ingredients by the ISO 16128 standard. This study evaluated six biobased and five synthetic film formers for their transfer resistance properties, as well as their effect on the quality of lipsticks. Lipstick quality was established and judged by measuring friction, pay-off, hardness, and color. For performance evaluation, a new in vitro transfer resistance test method was developed. All film-forming materials used in the study helped to decrease the percentage of lipstick transferred to a surface. Glyceryl stearate, trimethylsiloxysilicate, and polyamide-8 prevented transfer significantly (p < 0.05) compared to the control with no film former. Waxy compounds produced formulations with the best transfer resistance abilities overall. The new in vitro transfer resistance test yielded meaningful results and was able to compare the efficacy of the film-forming agents. Based on this study, it can be concluded that select biobased film formers can be used as effective substitutes for synthetic film-forming ingredients in lipsticks.
We tested a commercial lac dye on bleached hair and gray hair. For hair bleached with 6% lac dye in buffers at pH 4, 5, 6, and 7, the CIE a* indexes were 14.97 +/- 0.47, 13.34 +/- 0.15, 10.12 +/- 0.23, and 10.04 +/- 0.60, respectively, after 8 washes. Dyeing with 6% lac and using the mordants 0.1% ferrous sulfate and 1% longan wood ash produced CIE L* indexes of 22.38 +/- 0.09 and 26.65 +/- 0.05, respectively, after 8 washes. Examination of hair cross sections revealed that ferrous sulfate gave the best result, allowing lac dye to permeate 10 & micro;m into the hair. A solution of 6% lac dye rendered gray hair red (CIE a* index of 23.56 +/- 0.19). In summary, lac dye appears red in an acidic environment, and the addition of metallic mordants increases color fastness and darkness. Hair dyeing with a variety of hues using lac dye can be done by manipulating pH or mordants, such as ferrous sulfate or longan wood ash.
