Poster Language: English Category: Personal Care / Skin Care Retinol is well-established in cosmetics as an anti-ageing ingredient. It is known to increase cell proliferation and production of extracellular matrix elements such as hyaluronic acid. Anti-ageing products containing retinol may therefore decrease wrinkles and improve skin texture. Unfortunately, retinol also suffers from chemical instability and the potential to irritate skin. To circumvent these issues, several derivatives of retinol have been developed with improved stability while still retaining efficacy. Eastman’s derivatives are based on the Eastman GEM biocatalytic technology and contain unsaturated fatty acids; either purified linoleic acid or a blend derived from sunflower seed oil. In this poster, results will be shown for three studies: a clinical study, a human repeat insult patch test (hRIPT) study and formulation stability. The clinical test evaluated the efficacy of an antiaging formulation containing 0.1% of Retinyl sunflowerseedate among thirty-seven subjects, over 12 weeks. The assessment was carried out based on appearance of fine lines, wrinkles, and uneven skin tone. The hRIPT study aimed to assess skin safety determined by a human repeat insult patch test among 54 panelists. Lastly, the stability test was performed over 12 weeks under room temperature and 50°C to check remaining active content, color changes and best antioxidant performance during this period. The results confirm the suitability of Retinyl sunflowerseedate as an excellent choice for anti-aging formulations.

Date: Wednesday, 13 October 2021 - Friday, 15 October 2021

Poster Language: English Category: Fundamental Research Certainly, ionic liquids turn out to be a group of chemical compounds that made a breakthrough in chemical research. The phenomenon of ionic liquids is their possibility to design a compound by combination of desired cation and anion with targeted physicochemical properties. Among various application of ionic liquids, particularly considerable is the employment of Surface Active Ionic Liquids (SAILs) as innovative surfactants. Their effective reduction of surface tension leads to the replacement of traditional surfactants. The aim of this study was to investigate the new type compound surface activity in the aquatic environment. The surface tension was determined using the pendant drop method. This method consists of fitting the Young– Laplace equation to the digitized shape of a drop suspended from the end of a capillary tube. The image of the drop was taken from a charge coupled device camera. The following parameters were determined: surface tension (γCMC), critical micelle concentrations (CMC) and efficiency of surface adsorption on an air–water interface (pC20). Also, wettability of morpholinium ionic liquids was measured using the contact angle (CA). Wettability measurements were carried out on different surfaces to determine the correlation between the surfactants and the wetted surface area. The presented studies showed significant surface activity of the herbicidal ionic liquids. Moreover, it has been proved that with prolongation of alkyl chain the surface activity of ionic liquids increased.

Poster Language: English Category: Fundamental Research Introduction: Oily, acne-prone skin requires specific, non-aggressive cleansing, based on the use of surfactants capable of removing excess sebum but at the same time not irritating and respecting or restoring the skin barrier. This can be achieved by using a blend of mild functional surfactants and conditioning substances. Materials: Three mild surfactants were used: Sodium cocoyl alaninate (A), an anionic amino acid surfactant, Cocoyl methyl glucamide (G), a sugar-based with conditioning properties, Laureth-7 citrate (P), an anionic surfactant suitable for sensitive skin with antimicrobial properties, and an antimicrobial conditioning PCA ethyl cocoyl arginate (C). Methods: Rheological analyses were carried out to determine the viscosity by using an Anton Paar MCR 101 rotational rheometer and dimensional analysis of the micelles was performed using dynamic light scattering (DLS- Malvern Zetasizer Nano Series). Results: The surfactant mixtures were first of all studied in the different concentration ratios, keeping the total amount of surfactants constant at 15% to select the ratio with the best yield. Subsequently, mixtures with the total amount of surfactants of 12.5% and 10% were evaluated with the same concentration ratios between the components. Finally, the effect of the inclusion of PCA ethyl cocoyl arginate (C) within the formulation was evaluated, which was found to be able to increase both the viscosity of the product and the average size of the micelles. Conclusion: The study shows how a systematic and scientific methodological approach obtained through the instrumental characterization of the viscosity and of the size of the micelles have made it possible to obtain a specific and effective cleansing product for oily or acne-prone skin, whose functionality and compliance of use have been studied in vivo under dermatological control on 20 subjects.

Poster Language: English Category: Fundamental Research By adding small amounts of amphiphilic diblock copolymers like poly(ethylene oxide)-co-poly(ethylene propylene) (PEO-PEP) to water – oil – nonionic surfactant systems, Jakobs et al. showed in 1999 that the efficiency of medium-chain surfactants to solubilize equal amounts of water and oil can be strongly increased (so-called efficiency boosting). In order to obtain a similar boosting while also circumventing the drawback of a difficult large-scale synthesis, two new types of amphiphilic polymers were used in this work, namely poly(ethylene oxide)-poly(alkyl glycidyl ether)s (PEO-PAlkGE) and their carbonated poly(ethylene oxide)-poly(carbonate alkyl glycidyl ether) derivates (PEO-PCO2AlkGE). By studying their influence on the phase behavior of ternary nonionic microemulsions containing different oils, ranging from the medium-chain n-decane (C10H22) to the long-chain n-octacosane (C28H58) to the technical-grade Sasolwax 5805 (equivalent alkane carbon number of 30.8), a significant increase in efficiency was found for both amphiphilic polymer types. This strong boosting effect was further observed for systems with technical-grade surfactants, which could be of interest for industrial applications where a reduction in surfactant needs is of substantial economic as well as ecological advantage. Endo et al. attributed this strong efficiency increase to the adsorption of amphiphilic copolymers into the surfactant membrane, whereby the boosting was found to scale with the number density of copolymers in the membrane and the end-to-end distances of hydrophilic and hydrophobic polymer blocks. In this work, end-to-end distances of PEO and PAlkGE blocks were determined by small-angle neutron scattering (SANS) or calculated from literature. For n-decane microemulsions, the boosting effect of the new PEO-PAlkGE’s and the extensively investigated PEO-PEP’s could be scaled on top of each other. A different scaling was found for n-octacosane microemulsions, which was attributed to the polymers behaving more like ideal chains at elevated temperatures.

Poster Language: English Category: Fundamental Research The aim of this master thesis is the systematic investigation of alkoxylated alkyl ether carboxylic acids for their application in metal cleaning. The investigated ether carboxylic acids are different in the alkoxylation species (EO & PO), the alkoxylation type (pure EO & PO or blocks of EOPO & POEO) and the degree of alkoxylation. A structure-property relationship was established by determining various physical chemical parameters; cloud point, electrolyte stability and foam behavior. Based on the investigations, a linear increase in the cloud point of the cleaner formulations with increasing ether carboxylic acid content was observed. Based on this, the hydrotropy of the individual molecules in the metal cleaner formulation was determined. A correlation between the hydrotropy increase and the type and position of alkoxylation was detected. The propoxylated and propoxylated ethoxylated ether carboxylic acids showed a significantly stronger hydrotropic effect. An improvement in the electrolyte stability of the cleaner solutions was also measured with increasing ether carboxylic acid content. Cleaners with propoxylated and propoxylated ethoxylated ether carboxylic acids had stronger foaming behavior compared to the corresponding ethoxylated and ethoxylated propoxylated derivatives. The cleaning efficiency study was determined using a reproducible method. A commercially available ethoxylated and propoxylated nonionic surfactant was used as a benchmark in this study. The cleaning efficiency increased up to a certain level of alkoxylated alkyl ether carboxylic acids in the formulation and the cleaning temperature and time were reduced compared to the benchmark. The relationship between dynamic surface tension and cleaning performance described in the literature was confirmed. Based on these results, it was possible to predict the cleaning performance of the different surfactant ratios and confirm this by practical measurements. The longevity of the cleaning bath doubled without significant loss of cleaning performance by adding ether carboxylic acids. This increased the throughput of cleaning cycles.

Date: Wednesday, 13 October 2021 - Friday, 15 October 2021

Poster Language: English Category: Personal Care / Skin Care BACKGROUND: Today’s global trends in sustainability and mindfulness have gained tremendous impact on lifestyle and consumer behaviour. In view of cosmetics, an increased awareness on convenient, intensive skin care is key, implicating superior product efficacy but also novel test designs for claim support. Many study designs to evaluate cosmetics are published with objective or subjective parameters [1-3]. The present work expands the opportunities for evaluation by focusing on long-lasting effectiveness. A test design with 3-week treatment succeeded by 1-week regression phase was developed. METHODS: The investigation was divided into study A and B. Study A was conducted to evaluate the effectiveness and regression, i.e. maintenance of effectiveness during follow-up (n=18, female, age: 53.5±11.2). After measurement of skin hydration [4] and assessment of skin dryness and feeling (10-point scale) at baseline (t0) the product was applied for three weeks. Further examinations were performed after 3-week product use (t1) and additionally 24h (t2), 48h (t3), 72h (t4), 96h (t5) and 7 days (t6) thereafter. Study A was complemented by study B: questionnaire-based evaluation after 3-week by 33 female subjects (age: 49.4±12.5). RESULTS: Study A showed significantly higher skin hydration compared to the untreated test site after 3-week of product use. The hydration lasted up to 96h after last application. Moreover, after 3-week of product use significant difference in skin dryness and feeling were observed and remaining throughout the regression phase. In study B the subjects agreed to all statements, including long-term effectiveness. CONCLUSION: The present work shows long-lasting, sustainable effects on skin hydration and caring properties after 3-week application. Especially the follow-up examination provides a suitable approach to uncover and evaluate such superior, convenience-related skin care effects. Finally, such novel study designs allow to highlight innovative, cosmetic efficacies and product claims, thereby addressing contemporary consumer needs in cosmetics and beyond.     

Poster Language: English Category: Personal Care / Skin Care BACKGROUND: Current global trends and increasing consumer needs demand superior cosmetic product efficacies, requiring a constant evolution of test designs for product evaluation. Dexpanthenol (DEX) is broadly used for decades as ingredient in various cosmetic applications and thereby known for several proven functions [1], like increasing skin hydration, supporting moisture retaining [2], and enhancing epidermal barrier recovery [3]. In contrast, data concerning DEX kinetic and penetration are rare. Therefore, the present work focuses on the penetration of DEX. METHODS: Three pilot tests with Raman measurements were conducted to evaluate DEX penetration after application of a given o/w emulsion (Part I, II, III). For each test part, the study panel, test site, application mode, and measurement set-up were differently defined. RESULTS: DEX as active ingredient of the investigated skin care lotion is well detectable on the skin surface and down to a skin depth of 10μm up to 20μm. Occlusive conditions led to DEX penetration into the stratum disjunctum and as well into the stratum compactum. On hydrated skin DEX penetrates into the stratum disjunctum at measurable amounts. After 5 days open product application DEX is measurable even 12-16 hours after the last application and was significantly enriched in the upper layers of the stratum corneum. CONCLUSION: Comparing the test results, DEX could be detected in the stratum corneum down to a skin depth of 5, 10, and 20µm, depending on the test set-up. Such investigations provide knowledge on the interaction between mode of application, measurement set-up, and active ingredient penetration. Finally, the present work helps to improve product development regarding active targeting activities and additionally provides insights to choose an appropriate test set-up for such product investigations.

Poster Language: English Category: Personal Care / Green Cosmetics Consumers learned that keratin is one of the most important protein for hair repair and force improvement. However the keratin is obtained via animal source, and the consumers prefer plant based ingredients. 　 The aim of this study is to identify an ingredient that can replace the keratin by a vegetal source one. 　 The product tested is SHR (INCI name: Glycerin, Triticum Vulgare Protein, Water), once it presents similar amino acids profile. SHR was designed based on a gentle extraction process allowing an extraction of a Gliadin, a unique wheat protein with superior natural substantivity and film form property. Whole and untransformed, SHR can be considered a smart protein because it repair the hair where it most need. Also, SHR can penetrate in the hair fiber, decreasing the hair breakage also it can bond the split ends. 　 Once keratin is well known as an ingredient that improves the hair fiber force and strength, it was done an evaluation of mechanical properties of hair using tensile assessment comparing keratin and SHR. 　 Two groups were tested: SHR in 1.0% in shampoo and 1.0% in conditioner, and compared with hydrolyzed keratin at 2% in shampoo and 2% in conditioner. It was selected 3 bleached Caucasian hair tresses per treatment. After the products application, it was collected 45 fibers from each tress and analyzed.　 SRH showed similar performance of Keratin with half concentration. Both ingredients could improve the hair force and resistance in the elastic modulus, stress at 15%, break extension and break stress parameters.　 Based on the amino acids profile and the results it can be concluded that SHR can be a green alternative for keratin.

Poster Language: English Category: Personal Care / Fundamental Research Phospholipid (PL) liposomes are of central importance for industrial formulations in pharmacology and cosmetics. Typically, they are obtained by injecting a concentrated ethanolic PL solution (or other alcohol) into water. Subsequent application of shear reduces the liposome size and makes them colloidally stable. However, despite the importance of this process, still little is known about the mesoscopic structural changes taking place during liposome formation and the role played by the alcohol. This is even more critical for industrial formulations, which normally in addition contain active agents. The purpose of this study was to define the effect of short-chain alcohols in fluid bilayers. This was done by analyzing different PL liposome formulations prepared by extrusion at varying alcohol content. Using light scattering methods, an influence on vesicle size became apparent, with an overall tendency of vesicle shrinkage at increasing alcohol content. Furthermore, alcohol influence on bilayer permeability was investigated through fluorescent dye experiments. The liposomal systems will be studied by means of neutron scattering. In particular, by small angle neutron scattering (SANS), exploiting contrast variation between lipids and solvents. This will elucidate how the different solvent molecules distribute within the systems. In addition, stiffness of the bilayers to changing solvent quality and incorporation of additives will be studied by neutron spin echo spectroscopy (NSE). Understanding how alcohol molecules influence the structure and dynamics of phospholipid bilayers will render key information to develop more stable and functional liposome formulations.