The physico‐chemical properties and protein denaturation potential of surfactant mixtures

Abstract

Synopsis Protein denaturation was investigated to establish an in vitro evaluation method of surfactants in connection with their in vivo irritation potency to human skin. Eventually a new method with simplicity and high reproducibility was established by using quantitative analysis with gel-permeation chromatography (GPC). The protein denaturing potency of the commercially available surfactants was measured by using the developed method. Synergistic reduction in protein denaturation was observed in the mixed systems of anionic and amphoteric surfactants. The synergistic reduction was explained in terms of the physico-chemical properties of the mixed surfactants. A possible mechanism is the remarkable lowering of the total monomer concentration by the formation of hydrophobic complexes between the anionic and amphoteric surfactants.

Human Cutaneous Response to a Mixed Surfactant System: Role of Solution Phenomena in Controlling Surfactant Irritation

“…This effectively demonstrates the importance of co-surfactant levels high enough to minimize both the ratio of monomer (SLS/ AEOS) and the levels of SLS monomers in the surfactant solution. Such solution phenomena for this system may explain surfactant interactive effects reported for other systems [3][4][5][6],…”

“…This hypothesis was proposed by Gracia-Dominguez et al [3] and Miyazawaetal. [6] based on the observation that mix tures of SLS and milder surfactants interact synergistically to reduce surfactant binding to the stratum corneum [3.5] or denaluraiion of ovalbumin [6]. From those studies they hypothesized that there were interactions occurring between the surfactants in solution.…”

“…A relationship between surfactant critical micelle concentration and in vitro skin response has been demonstrated [1], Even more complex are the skin responses to surfac tant mixtures. Several authors [1,[3][4][5][6] have reported that surfactants interact in mixed solutions to reduce in vivo 1 Abstract published in J Invest Dermatol 1988:90:601.…”

Corticosteroids of Clinical Value in Lipid-Soluble-Chemical-Induced Irritation in Man?

“…The lipophilic NAA, utilized in this study, exhibits different physicochemical characteristics than the hydrophilic SLS and, thus, may irritate the skin using a different mechanism of action. Skin barrier function is only minimally influenced by NAA [18] while greatly damaged by SLS [19]. Betamethasone-17-valerate and petrolatum may be more beneficial in decreasing NAA irritation as opposed to SLS irritation.…”

Silicon Image Sensor Technology for in vivo Detection of Surfactant-Induced Corneocyte Swelling and Drying

“…In vitro studies performed on corneocytes have shown many physicochemical interactions between these cells and surfactants [8, 11, 12, 13, 14]. One of the earliest events following protein denaturation is perceived as corneocyte swelling [15, 16, 17, 18, 19].…”