Effects of Oils and Emulsifiers on the Skin Penetration of Stearyl Glycyrrhetinate in Oil-in-Water Emulsions

Abstract

We investigated whether an emulsifier or an emulsified oil affects the skin penetration of stearyl glycyrrhetinate (SG) when it is applied in an oil-in-water (O/W)-type emulsion under finite dose conditions in vitro. SG has a high molecular weight (MW: 723) and high lipophilicity (log P: 15.6). Skin penetration of SG applied with O/W emulsions was evaluated using 6 types of emulsifiers that are commonly used in cosmetics; however, no significant differences were observed between these emulsifiers. When applied with liquid paraffins in oil phase, SG skin penetration increased significantly as the molecular weight of the liquid paraffin decreased. The skin penetration of the fluorescent dye 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate (DiI; MW: 834, log P: 23.2) also increased with O/W-type emulsions containing liquid paraffins of lower molecular weights. These results indicate that use of O/W-type emulsions with an appropriate oil phase can improve SG skin penetration.

Effect of Esters on the Permeation of Chemicals with Different Polarities through Synthetic Artificial Membranes Using a High-Throughput Diffusion Cell Array

“…8,9) In the present study, the effect of esters on artificial membrane permeation were evaluated and the obtained relationships between physical properties and the amount of compounds that permeated were almost similar to previous results that evaluated rat, [15][16][17] porcine, 19,20) and human 18) skins. Thus, although future research on the correlation between the permeability of artificial membrane and porcine or human skin from esters will be needed, silicone and Strat-M ® membranes might be useful in the development of pharmaceutical and cosmeceutical products.…”

“…It has also been found that ketoprofen exhibited increased permeation through hairless rat skin when it was dissolved in low MW esters, 16) and the permeability of stearyl glycyrrhetinate through Yucatan micropig skin with a finite dose was affected by the surface tension and MW of the vehicle. 19) Thus, the common properties of these permeation enhancers are their low MWs and surface tension. Similarly, in the present study, it was evident that the amounts of the model compounds that permeated through the membranes were higher when esters with low MWs and low surface tension were used as a vehicle.…”

“…The effect of fatty acid esters on the skin permeation of indomethacin and ketoprofen and the effect of diesters on the skin permeation of non-steroidal anti-inflammatory drugs has been reported. [15][16][17] In addition, previous studies found that the permeability of haloperidol was affected by the wettability and surface tension of the formulation.18) Furthermore, the penetration of stearyl glycyrrhetinate through Yucatan micropig skin at a finite dose was affected by the molecular weight and surface tension of the vehicles, 19) and skin permeation of model compounds through porcine skin was affected by the viscosities of the vehicles. 20) These physical properties could be a key parameter to enhance the skin permeation of chemicals.…”

“…18) Furthermore, the penetration of stearyl glycyrrhetinate through Yucatan micropig skin at a finite dose was affected by the molecular weight and surface tension of the vehicles, 19) and skin permeation of model compounds through porcine skin was affected by the viscosities of the vehicles. 20) These physical properties could be a key parameter to enhance the skin permeation of chemicals.…”

Analysis of Human and Porcine Skin in vivo/ex vivo for Penetration of Selected Oils by Confocal Raman Microscopy

“…oleic acid and glyceryl trioleate) disrupt the stratum corneum lipids, thus enhancing the penetration [21,22,23,24]. Leite-Silva et al [22] reported that the formulation containing paraffin oil acts as a penetration enhancer for zinc oxide nanoparticles which, along with titanium dioxide nanoparticles, normally do not penetrate through the barrier of the stratum corneum [25,26,27,28].…”