Proderm technology: a water- based lipid delivery system for dermatitis that penetrates viable epidermis and has antibacterial effects.

BACKGROUND: A defective skin barrier and bacterial colonization are two important factors in maintenance and progression of atopic dermatitis and chronic allergic/irritant hand dermatitis. A water-based lipid delivery system containing physiologic lipids was previously shown to be a useful adjunct in the treatment of hand dermatitis. We tested the ability of this formulation to penetrate into the viable epidermis and in addition assessed its antibacterial properties. METHODS: Epidermal penetration of the product was assessed by fluorescence microscopy. Recovery of Escherichia coli and Staphylococcus aureus MRSA from skin treated with Neosalus® foam was quantified. RESULTS: Components of Neosalus® penetrated the stratum corneum and were distributed throughout the viable epidermis. Neosalus® significantly decreased recovery of both Staphylococcus aureus and Escherichia coli from the skin surface. CONCLUSIONS: The ability of components of Neosalus® to be taken up into the viable epidermis and potentially made available for incorporation into the barrier lipids, combined with antibacterial properties, indicate that this formulation may be valuable not only in chronic hand dermatitis, but also in various other forms of dermatitis. TRIAL REGISTRATION: Current Controlled Trials ISRCTN18191379 , 28/12/2018, retrospectively registered.

A new water-based topical carrier with polar skin-lipids.

A new water-based topical formulation is presented that aims at providing good penetration properties for both lipophilic and hydrophilic drugs with as small a disturbance of the skin barrier function as possible. The formulation contains dispersed lipids in a ratio resembling that of human skin. The capacity to deliver is addressed in this first study while the mild effect on skin will be presented later. Three variations of the lipid formulation were investigated by use of pigskin in vitro diffusion cell. The hydrophilic 5(6)-carboxyfluorescein (CF) and the lipophilic acridine orange 10-nonyl bromide (AO) were used as model drug substances. The results showed that the delivery properties of the new formulation exceeded that of the references (vaseline and xanthan gum gel). The effect was largest for lipophilic AO where all lipid matrix formulations were superior in amount detected in the skin. The results for the hydrophilic CF were also promising. Especially efficient was the lipid formulation containing the non-ionic adjuvants tetra ethylene glycol monododecyl ether and polyoxyethylene 23 dodecyl ether. The additional in vivo study suggests that the used in vitro model has qualitative bearing on relevant in vivo situations.

Linkage identity is a major factor in determining the effect of PEG-ylated surfactants on permeability of phosphatidylcholine liposomes.

The permeability effects induced by single-chained and double-chained poly(ethylene glycol)-surfactants were investigated by measuring the leakage of the fluorescent dye 5(6)-carboxy fluorescein from EPC liposomes. The standard incorporated amount of the surfactants was 5 mol%. Depending on the size of the poly(ethylene glycol) chain and especially on the type of linkage between the polymer and the hydrophobic moiety different leakage profiles were obtained. The presence of a long PEG-polymer resulted in a slower leakage compared with a short analogue. More importantly, the linkage identity was decisive for whether an overall reduction or increase in permeability was obtained. When the hydrocarbon chains were attached to the PEG chain via an ether or an ester the leakage increased compared to pure EPC liposomes. In contrast, if the link was an amide, the leakage was significantly reduced. This effect is assumed to originate from headgroup-headgroup interactions, and most probably hydrogen bonding, between amide and phosphate groups of the PEG-surfactant and the EPC, respectively.

Rheological properties of phospholipid-stabilized parenteral oil-in-water emulsions--effects of electrolyte concentration and presence of heparin.

The rheological properties of the parenteral oil-in-water emulsion Intralipid were investigated. The viscosity data at different phase volumes correlated well with that obtained via a theoretical model developed by Yaron and Gal-Or. The model also describes the temperature dependence well. The effects of electrolyte addition were also investigated. Monovalent sodium chloride had practically no influence on viscosity. Calcium chloride, on the other hand, had a large impact on viscosity even at low concentrations. It was shown that the obtained maximum in viscosity coincided with the zeta-potential being close to zero. The resulting increase in viscosity is due to flocculation that leads to an increase in apparent phase volume. A similar behaviour was obtained with magnesium chloride with the difference that the maximum in viscosity was shifted to higher electrolyte concentrations. This is interpreted as that because magnesium binds strongly to the hydration water than does calcium. The addition of the negatively charged anti-coagulant heparin causes flocculation in the presence of small amounts of calcium. The amounts of calcium needed for such bridging flocculation is lower than what is needed in order to create a positive potential at the surfaces of the droplets. A fraction of the flocs is not broken down even by extensive shear.