Soon Sik Kwon

Physicochemical properties of pH-sensitive hydrogels based on hydroxyethyl cellulose–hyaluronic acid and for applications as transdermal delivery systems for skin lesions

We investigated the physicochemical properties of pH-sensitive hydroxyethyl cellulose (HEC)/hyaluronic acid (HA) complex hydrogels containing isoliquiritigenin (ILTG), and discussed potential applications as transdermal delivery systems for the treatment of skin lesions caused by pH imbalance. HA has skin compatibility and pH functional groups and HEC serves as scaffold to build hydrogels with varied HCE:HA mass ratio. Hydrogels were synthesized via chemical cross-linking, and three-dimensional network structures were characterized via scanning electron microscopy (SEM). The swelling properties and polymer ratios of the hydrogels were investigated at pH values in the range 1-13. HECHA13 (i.e., an HEC:HA mass ratio of 1:3) was found to have optimal rheological and adhesive properties, and was used to investigate the drug release efficiency as a function of pH; the efficiency was greater than 70% at pH 7. Antimicrobial activity assays against Propionibacterium acnes were conducted to take advantage of the pH-sensitive properties of HECHA13. At pH 7, we found that HECHA13, which contained ILTG, inhibited the growth of P. acnes. Furthermore, HECHA13 was found to exhibit excellent permeability into the skin, which penetrated mostly via the hair follicle. These results indicate that this pH-sensitive hydrogel is effective as a transdermal delivery system for antimicrobial therapeutics, with potential applications in the treatment of acne.

Physical characterization and in vitro skin permeation of solid lipid nanoparticles for transdermal delivery of quercetin.

Quercetin, a phenolic compound isolated from plants, can act as an antioxidant to protect the skin from oxidative stress induced by ultraviolet rays. The aims of this work were (i) to compare the physical characterization of quercetin‐loaded solid lipid nanoparticles (QSLNs) and (ii) to investigate the enhanced skin permeation of quercetin using QSLNs.

Cell penetrating peptide conjugated liposomes as transdermal delivery system of Polygonum aviculare L. extract

In this study, Polygonum aviculare L. extract, which has superior antioxidative and cellular membrane protective activity, was loaded onto cell penetrating peptide (CPP) conjugated liposomes to enhance transdermal delivery. The physical characteristics of typical liposomes and CPP-conjugated liposomes containing P. aviculare extract were evaluated. The particle sizes of both liposomes were approximately 150 nm. Whereas the zeta potential of typical liposomes was -45 mV, that of CPP-conjugated liposomes was +42 mV. The loading efficiency of P. aviculare extract in both liposomes was calculated to be about 83%. Fluorescent-labeled liposomes were prepared to evaluate cellular uptake and skin permeation efficiency. Using flow cytometry, we found that CPP-conjugated liposomes improved cellular uptake of the fluorescent dye as compared with the typical liposomes. In addition, the skin permeation of CPP-conjugated liposomes was proved higher than that of typical liposomes by confocal laser scanning microscopy studies and Franz diffusion cell experiments. The improved cellular uptake and skin permeation of the CPP-conjugated liposomes were due to the cationic arginine-rich peptide. In vivo studies also determined that the CPP-conjugated liposomes were more effective in depigmentation and anti-wrinkle studies than typical liposomes. These results indicate that the CPP-conjugated liposomes could be effective for transdermal drug delivery of antioxidant and anti-aging therapeutics.

Enhanced skin delivery of liquiritigenin and liquiritin-loaded liposome-in-hydrogel complex system

To study the permeation of liquiritigenin (LQG) and liquiritin (LQ) as licorice flavonoids into the skin, we prepared ceramide liposome‐in‐cellulose hydrogel complex system.

Antioxidative Effect and Tyrosinase Inhibitory Activity of the Unripened Fruit Extract of Rubus coreanus Miquel

In this study, the antioxidative effects and inhibitory activities of unripened fruit extract of Rubus coreanus Miquel (R. coreanus Miquel) on tyrosinase were investigated and the potential applicability as a cosmeceutical ingredients was evaluated. All experiments were performed with 50% ethanol extract, ethyl acetate fraction and aglycone fraction of unripened fruit extract of R. coreanus Miquel. The DPPH (1,1-diphenyl-2-picrylhydrazyl) scavenging activites () of 50% ethanol extract (6.56 ) and ethyl acetate fraction (6.14 ) of unripened fruit extract of R. coreanus Miquel were higher than (+)--tocopherol (8.98 ), which is known as a typical hydrophobic antioxidant. Reactive oxygen species (ROS) scavenging activities () of 50% ethanol extract (0.83 ), ethyl acetate fraction (0.84 ) and aglycone fraction (1.13 ) of R. coreanus Miquel on ROS generated in system were higher than L-ascorbic acid (1.5 ), which is known as s typical hydrophilic antioxidant. The cellular protective effect of extract and fraction of unripened fruit extract of R. coreanus Miquel on the rose bengal sensitized photohemolysis of human erythrocytes was increased in a concentration dependent manner (1 ~ 50 ). And 50% ethanol extract in 50 showed the most protective effect among extracts (

Preparation and characterization of W/O microemulsion for removal of oily make-up cosmetics

In the present study, W/O microemulsions (MEs) were prepared for efficient removal of oily make‐up cosmetics and the detergency characteristics were studied.

Formation of stable hydrocarbon oil-in-water nanoemulsions by phase inversion composition method at elevated temperature

Stable hydrocarbon oil (hexadecane, C16)/nonionic surfactant (HCO-60, Span 80)/water system oil-in-water nanoemulsions were prepared by the phase inversion composition method at elevated temperature. To minimize droplet size, the composition ratio for stable nanoemulsions, we experimented by changing the HLB value, oil/surfactant ratio, and droplet volume fraction. When the HLBmix value 11, the nanoemulsions show a minimal sample droplet size of 360.3 nm. By varying the oil/surfactant ratio from 0.6 to 1.4, we found the optimum oil/surfactant ratio to be approximately 0.6, which corresponds to the minimum droplet size of 71.8 nm. We also varied the droplet volume fraction; when the droplet volume fraction is 0.06, the droplet size is very small. For the emulsion with the minimal droplet size, the polydispersity index is less than 0.3, which reflects a good monodispersity of the nanoemulsion. Viscosity and electrical conductivity measurements were carried out for determining the internal structure of the bicontinuous phase during the emulsification. When the water content ranges from 4 to 6 w/w%, the systems may have a bicontinuous or lamellar phase. Oil-in-water nanoemulsion stability assessment was performed by observing the droplet size as a function of storage time; we did not observe any change in droplet size over the course of a month.

Physical Characterizations and In Vitro Skin Permeation of Elastic Liposomes for Transdermal Delivery of Polygonum aviculare L. Extract

In this study, Polygomun aviculare L. (P. aviculare L.) extract loaded elastic liposomes (ELPs) were inves- tigated to enhance the transdermal delivery of P. aviculare L. extract composed of various flavonoids. ELPs were com- posed of egg phospholipids (PC) and edge activator (Tego ® care 450) and the physical properties and in vitro permeation studies of ELPs were performed. Particle size ranged from 148.1 to 262.2 nm and deformability index was recorded as 11.5~25.4. Loading efficiency was from 53.1 to 66.3%. In vitro skin permeation studies using Franz diffusion cell dem- onstrated that ELP-4 having ratio of 85:15 for PC to Tego ® care 450 exhibited the higher skin permeability than ELP- 1, the general liposome without Tego ® care 450. It was visually seen by fluorescence image restoration microscopy. The findings suggest that ELP-4 selected as the optimal formulation could be used as useful formulation for transdermal deliv- ery of the extract.

Screening of Effective Extraction Conditions for Increasing Antioxidant Activities of Licorice Extracts from Various Countries of Origin

본 연구에서는 한국 및 중국산 감초(Glycyrrhiza uralensis), 그리고 우즈베키스탄산 감초(Glycyrrhiza glabra)를 대상으로 추출용매, 추출온도, 추출시간 등 추출조건별 추출물을 제조하고 이들 추출물들의 추출 수율과 항산화 활성을 비교하여 최적의 추출조건을 선정하였다. 항산화 활성 중 자유 라디칼(1,1-phenyl-2-picrylhydrazyl, DPPH) 소거활성은 85% 에탄올로

Antioxidative Effects of Inula britannica var. chinensis Flower Extracts According to the flowering period and species of Inula britannica var. chinensis

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