摘要:

SynopsisComplexes of glycosaminoglycans and certain cationic polymers have been identified which provide utility in skin and hair care applications. The combination of biologically engineered hyaluronic acid and the cationic cellulose polymer, polyquaternium‐10, results in a unique, stable, multifunctional, association complex with enhanced polymer functionality. Complexation of the anionic and cationic polysaccharide polymers renders hyaluronic acid substantive to keratin, as evidenced by zeta potential changes of the surface charge of hair via electrokinetic streaming potential measurements. Radiolabelling techniques show as much as a ten‐fold increase in bound hyaluronic acid on hair after water rinsing. The resulting ‘enhanced’substantivity of hyaluronic acid, as part of the complex, thus extends the time hyaluronic acid remains in contact with keratinous surfaces, prolonging its humectant, moisturizing and skin‐smoothenin

ISSN:0142-5463    

DOI:10.1111/j.1467-2494.1994.tb00099.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SynopsisThe cutaneous tolerability of detergent formulations can be improved by means of suitable additives. Exogenous proteins, for example, are able to reduce the skin irritation potential of surfactants according to a double mechanism: they complex the surfactant molecules lowering the concentration of their free monomeric species; they link to the skin keratin forming a protective colloidal layer that shields the denaturing attack of surfactants. Protein derivatives used as additives for detergency are usually prepared by partial hydrolysis of animal scleroproteins or plant reserve proteins. The main purpose of the hydrolytic cleavage is to make them water soluble and suitable for liquid products. Native, non hydrolysed wheat proteins have been recently introduced as active ingredients for detergents. Water solubility and stability are obtained by means of complexation with surfactants which also increases their actual hydrophobicity, an important parameter affecting cosmetic properties of proteins. The anti‐irritant properties of these new derivatives of detergents have been evaluated byin vitropredictive tests (swelling response of collagen membranes), by acute irritancyin vivomethods (occlusive patch tests) and by use tests (forearm washing test). Transepidermal water loss and electric capacitance have been adopted as investigation techniques to evaluate the skin integrity/damage after thein vivotests. The performance of native wheat protein‐surfactant complexes has been compared with traditional protein hydrolysates and to amphoteric surfactants as detergent additives. The results show a noticeable reduction of skin irritation in surfactant formulations with addition of native wheat prote

ISSN:0142-5463    

DOI:10.1111/j.1467-2494.1994.tb00100.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SynopsisThis paper reports preliminary results of a study carried out on liquid crystal emulsions added to three different inorganic sunscreens: ultrafine zinc oxide, ultrafine titanium dioxide (inorganic‐treated) and ultrafine titanium dioxide (organic‐treated hydrophobically).The aim of the work was to investigate the influence of chemico‐physical properties of inorganic sunscreens on the microstructure of cosmetic emulsions. The study was carried out using three different techniques: rheological measurements performed in dynamic conditions, to study the homogeneity of samples and their structural features; dispersion of powders in emulsions by optical microscopy and SEM/EDX analysis; and functionality of emulsions by UV spectroscopy, with adhesive tape as substrate.Results show that the different chemico‐physical properties of the micropigments lead to different interactions with emulsion components; these interactions may affect the functionality and microstructure of the whole system, with loss of st

ISSN:0142-5463    

DOI:10.1111/j.1467-2494.1994.tb00101.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SynopsisThe aim of this work was to check if the specific microstructure of a water/oil nonionic microemulsion could induce a modification of the bioavailability of a probe (methyl nicotinate). The vasodilatory drug effects were recorded by laser doppler velocimetryin vivo, in man. The results show a quicker activity, and a better release of the drug in the microemulsion, than in the well‐known kinetics of an aqueous solutio

ISSN:0142-5463    

DOI:10.1111/j.1467-2494.1994.tb00102.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SynopsisAlpha‐hydroxy acids are a common class of naturally occurring chemicals that have become increasingly popular for cosmetic use. Currently alpha‐hydroxy acids from both natural and synthetic sources are being used in skincare products. From lactic acid to complex natural blends, several different approaches have been adopted for the use of alpha‐hydroxy acids. This paper reviews the history of alpha‐hydroxy acids use in cosmetics and gives new data showing the increased rate of cell renewal by topical appl

ISSN:0142-5463    

DOI:10.1111/j.1467-2494.1994.tb00103.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY