Care Formulations (care + formulations)

Distribution by Scientific Domains

Selected Abstracts

Behenamidopropyl Dimethylamine: unique behaviour in solution and in hair care formulations

M. Minguet
Synopsis The rise of ecological awareness among consumers and industry has impacted the cationic surfactants market. The most used cationic surfactants present some drawbacks in this sense. Therefore, new molecules are being studied and developed which fulfil eco-toxicological requirements without losing performance. One of these surfactants is Behenamidopropyl Dimethylamine (BAPDMA). This biodegradable amidoamine, which converts into a cationic surfactant at acidic pH, shows outstanding water solubility, despite its very long alkyl chain. Its behaviour in solution has been exhaustively studied. The conditioning performance of this product is superior to that of commonly used cationic surfactants, providing a superior sensorial profile and improved combing force reductions on hair. Moreover, other applications for this product in the non-ionic form have been studied, such as conditioning agent in 2 in 1 shampoos, where it also shows colour protection effects, and as gelling agent in hair colouration creams. This multifunctional and high performance profile, together with an improved biodegradation and aquatic toxicity compared with currently used cationic surfactants, make this product a very interesting eco-friendly alternative for the hair care market. Résumé L'essor de la conscience écologique parmi les consommateurs et l'industrie a eu un fort impact dans le marché des tensioactifs cationiques. Les plus employés d'entre eux ont quelques désavantages de ce point de vue. À ce sujet, on est en train d'étudier et développer des nouvelles molécules qui accomplissent les conditions éco-toxicologiques, sans perdre leur efficacité adoucissante. Un de ces tensioactifs c'est la Behenamidopropyl Dimethylamine (BAPDMA). Cette amidoamine, qui est totalement biodégradable et non toxique pour l'environnement, évolue dans un tensioactif cationique à des pHs acides. Dans l'eau le produit montre une solubilité inespérément élevée, malgré qu'il a une chaîne alchilyque très longue. On a étudiéà fond son comportement en dissolution. L'efficacité de conditionnement du produit se montre supérieure à celle des tensioactifs cationiques employés habituellement, en donnant un profil sensoriel supérieur et en améliorant la souplesse de coiffure. En plus, pour ce produit, d'autres applications ont étéétudiées dans la forme non ionique, par exemple, son emploi comme agent conditionneur dans des shampooings 2 en 1, où il montre aussi un effet protecteur de la couleur et comme agent de texture dans des crèmes de coloration capillaire. Ce profil multifonctionnel et de haute efficacité, ainsi que un bon profil éco-toxicologique, en comparaison avec les tensioactifs cationiques employés actuellement, fait que la behenamidopropyl dimethylamine soit une très bonne alternative pour le marché du soin capillaire. [source]

Skin moisturization by hydrogenated polyisobutene,Quantitative and visual evaluation

N. Dayan
J. Cosmet. Sci., 60, 15,24 (January/February 2009) Synopsis Hydrogenated polyisobutene (HP) is used in topically applied cosmetic/personal care formulations as an emollient that leaves a pleasing skin feel when applied, and rubbed in after application. This effect, although distinguishable to the user, is difficult to define and quantify. Recognizing that some of the physical properties of HP such as film formation and wear resistance may contribute, in certain mechanisms, to skin moisturization, we designed a short-term pilot study to follow changes in skin moisturization. HP's incorporation into an o/w emulsion at 8% yielded increased viscosity and reduced emulsion droplet size as compared to the emollient ester CCT (capric/caprylic triglyceride) or a control formulation. Quantitative data indicate that application of the o/w emulsion formulation containing either HP or CCT significantly elevated skin moisture content and thus reduced transepidermal water loss (TEWL) by a maximal ,33% against the control formulation within 3 h and maintained this up to 6 h. Visual observation of skin treated with the HP-containing formulation showed fine texture and clear contrast as compared to the control or the CCT formulation, confirming this effect. As a result of increased hydration, skin conductivity, as measured in terms of corneometer values, was also elevated significantly by about tenfold as early as 20 min after HP or CCT application and was maintained throughout the test period. Throughout the test period the HP formulation was 5,10% more effective than the CCT formulation both in reduction of TEWL as well as in increased skin conductivity. Thus, compared to the emollient ester (CCT), HP showed a unique capability for long-lasting effect in retaining moisture and improving skin texture. [source]

Effects of lipid nanocarriers on the performance of topical vehicles in vivo

Mojgan Moddaresi PharmD
Summary Background/aims, Nanocarrier systems have been extensively studied for their suitability in personal care formulations. Theoretically, they could enhance skin delivery of active compounds, thereby improving in vivo efficacy of the products. As such the aim of this study was to evaluate the effect of a lipid nanocarrier (LNC) system loaded with tocopheryl acetate (TA) on the hydration, biomechanical properties, and antioxidant capacity of human skin, when used in two different vehicles, and compare it with a non-LNC formulation. Methods, TA-loaded lipid nanocarriers (TA-LNCs) were produced by the phase inversion method, using physiological lipids and purified by ultra-centrifugation. They were incorporated into a hydrophilic gel and foam, and their performance compared with a saturated TA solution in silicon oil. Skin hydration and biomechanical properties were measured by means of a corneometer and a cutometer, respectively, while a high-resolution spectrophotometer was used to assess skin redness after stimulation by methyl nicotinate in a micro-inflammatory test. Both short-term (3 h) and long-term trials (4 weeks) were performed. Results, The results confirmed that the LNCs enhanced skin hydration in both studies, while skin viscoelastic parameters remained practically unchanged during the 4-week study. The antioxidant assessment failed to show significant difference between the test sites. Conclusions, TA-loaded LNCs exhibited the ability to enhance skin hydration, while their effect on skin biomechanical properties and on antioxidant efficacy could not be statistically proved. [source]

Determination of molar mass and solution properties of cationic hydroxyethyl cellulose derivatives by multi-angle laser light scattering with simultaneous refractive index detection

Wei Gao
Abstract BACKGROUND: A complete understanding of the molar mass and solution properties of raw materials in bio/pharmaceutical products under bio-application and natural conditions ensures process control, product performance and quality. Biopolymers including polymeric cationic hydroxyethyl cellulose derivatives (e.g. Polyquaterium-10 or Polymer JR) have long been used in health care formulations including shampoos, lotions, eye drops and contact lens multi-purpose solutions. Previously reported molar masses and conformation of Polymer JR were based on size exclusion chromatography-related techniques, which required highly concentrated buffered salt solutions and organic solvent modifiers to prevent undesirable interactions, and did not represent the isotonic conditions in products and applications. RESULTS: This paper describes the characterization of Polymer JR in saline using a new approach that combines micro-batch mode multi-angle laser light scattering with simultaneous refractive index measurements (MB-MALLS-RI). Mass-average molar mass, z -average radius of gyration and second virial coefficient values in phosphate buffer saline (PBS) were obtained and are discussed in detail. CONCLUSION: The molar mass and solution properties of Polymer JR in PBS, with the same pH and ionic strength as most health care solution products, can be characterized using the MB-MALLS-RI technique. The approach is practical and can be widely used for the analysis of other cationic biopolymers. Copyright © 2009 Society of Chemical Industry [source]

Emollient molecule effects on the drying stresses in human stratum corneum

K. Levi
Summary Background Emollient molecules are widely used in skin care formulations to improve skin sensory properties and to alleviate dry skin but little is understood regarding their effects on skin biomechanical properties. Objectives To investigate the effects of emollient molecules on drying stresses in human stratum corneum (SC) and how these stresses are related to SC components and moisture content. Methods The substrate curvature method was used to measure the drying stresses in isolated SC following exposure to selected emollient molecules. While SC stresses measured using this method have the same biaxial in vivo stress state and moisture exchange with the environment, a limitation of the method is that moisture cannot be replenished by the underlying skin layers. This provides an opportunity to study the direct effects of emollient treatments on the moisture content and the components of the SC. Attenuated total reflectance Fourier transform infrared spectroscopy was used to determine the effects of emollient molecules on SC lipid extraction and conformation. Results Emollient molecules resulted in a complex SC drying stress profile where stresses increased rapidly to peak values and then gradually decreased to significantly lower values compared with the control. The partially occlusive treatments also penetrated into the SC where they caused extraction and changes in lipid conformation. These effects together with their effects on SC moisture content are used to rationalize the drying stress profiles. Conclusions Emollient molecules have dramatic effects on SC drying stresses that are related to their effects on intercellular lipids and SC moisture content. [source]