Gye Hwa Shin

Preparation of Chitosan-Coated Nanoliposomes for Improving the Mucoadhesive Property of Curcumin Using the Ethanol Injection Method

Chitosan-coated curcumin nanoliposomes (CS-Cur-NLs) were fabricated by the ethanol injection method (EIM), and their physicochemical properties were compared with the properties of those fabricated by the dry thin film method (DTFM). The mean size and zeta potential of CS-Cur-NLs gradually increased with CS concentration. The encapsulation efficiency of Cur-NLs prepared by EIM was 54.70%, which was significantly improved compared to that (42.60%) of Cur-NLs prepared by DTFM. Further improvement of encapsulation efficiency was attained (up to 64.93%) by EIM with 0.1% CS coating. The mucoadhesive property of Cur-NLs improved from 33.60 to 56.47% with CS coating. The results indicate that the encapsulated curcumin will show prolonged adsorption in the gastrointestinal tract because of higher mucoadhesion. Thus, EIM can be considered to be effective for food-grade delivery carriers with higher encapsulation efficiency and absence of harmful solvents. EIM-generated CS-Cur-NLs showed higher bioavailability, with enhanced high mucoadhesive property, storage stability, and encapsulation efficiency.

Curcumin-Eudragit® E PO solid dispersion: A simple and potent method to solve the problems of curcumin

Using a simple solution mixing method, curcumin was dispersed in the matrix of Eudragit® E PO polymer. Water solubility of curcumin in curcumin-Eudragit® E PO solid dispersion (Cur@EPO) was greatly increased. Based on the results of several tests, curcumin was demonstrated to exist in the polymer matrix in amorphous state. The interaction between curcumin and the polymer was investigated through Fourier transform infrared spectroscopy and (1)H NMR which implied that OH group of curcumin and carbonyl group of the polymer involved in the H bonding formation. Cur@EPO also provided protection function for curcumin as verified by the pH challenge and UV irradiation test. The pH value influenced curcumin release profile in which sustained release pattern was revealed. Additionally, in vitro transdermal test was conducted to assess the potential of Cur@EPO as a vehicle to deliver curcumin through this alternative administration route.

Preparation of a Capsaicin-Loaded Nanoemulsion for Improving Skin Penetration

Capsaicin o/w nanoemulsions with enhanced skin permeation were successfully prepared by controlling the ratios of the surfactant mixtures, oleoresin capsicum as the oil phase, and aqueous phase. Oleoresin capsicum contains 22.67 mg/g of capsaicin, which is an active and oil-soluble ingredient. Nonionic surfactants, Tween 80 and Span 80, were used to optimize the weight ratio of surfactant mixtures (85.98:14.02) by calculating the hydrophile-lipophile balance (HLB) value. The optimal processing conditions for stable nanoemulsions were investigated by using a ternary phase diagram. The mean droplet size of nanoemulsions ranged from 20 to 62 nm. Skin permeation studies were performed using a Franz diffusion cell. The permeation profiles and confocal laser scanning microscopy (CLSM) images supported that capsaicin nanoemulsion could well permeate all skin layers from the stratum corneum to the dermis. The selected nanoemulsions showed great potential as transdermal delivery carriers for enhancing the permeation of core materials.

Enhancement of Curcumin Solubility by Phase Change from Crystalline to Amorphous in Cur‐TPGS Nanosuspension

Nanosuspensions (NSs) were fabricated to enhance water solubility, dissolution rate, and oral adsorption of water insoluble curcumin using sonoprecipitation method. As a good stabilizer, d-α-Tocopherol polyethylene glycol 1000 succinate (TPGS) was used to improve the stability of curcumin-TPGS NSs (Cur-TPGS NSs). Ultrasonic homogenization (UH) could effectively enhance the solubility of curcumin and to produce homogeneous NSs with small particle sizes. Water solubility of curcumin was significantly improved from 0.6 μg/mL in pure water to 260 μg/mL in the mixture of curcumin and TPGS (1:10) with UH treatment. The mean particle size of Cur-TPGS NSs was decreased significantly after UH and maintained between 208 and 246 nm. Lyophilized powder of Cur-TPGS NSs was dissolved about 91.08% whereas the pristine curcumin powder was dissolved only 6.5% at pH 7.4. This study showed a great potential of Cur-TPGS NSs as a good nano-formulation of curcumin with enhanced solubility and improved oral adsorption.

Preparation of Chitosan‐Coated Nanostructured Lipid Carriers (CH‐NLCs) to Control Iron Delivery and Their Potential Application to Food Beverage System

Nanostructured lipid carriers (NLCs) and chitosan-coated NLCs (CH-NLCs) were prepared by a combined double emulsion and melt dispersion method. The physicochemical properties of them were investigated to determine the optimum conditions. At 3% emulsifier concentration, the NLCs showed about 191.0 ± 4.1 nm mean particle size and low polydispersity index value compared to those observed under other conditions. The encapsulation efficiency of CH-NLCs was 83.9% which was about 10% higher than that of NLCs. In vitro release test showed that low release amount of iron from the NLCs (11%) and CH-NLCs (5%) in simulated gastric condition within 3 h, whereas the iron release amounts of the NLCs and CH-NLCs were high (over 77%) in simulated intestinal condition because both NLCs and CH-NLCs were totally destructed in the intestinal condition after 3 h. In the thiobarbituric acid test, the absorbance of milk-fortified NLC and CH-NLCs was lower than that of original milk. Based on these results, CH-NLCs showed great potential for iron fortification in milk.

Adsorption behavior of β-lactoglobulin onto polyethersulfone membrane surface

The adsorption of whey protein onto polyethersulfone (PES) membrane was investigated by static adsorption experiments to understand fouling mechanism and optimize the process condition to minimize the membrane fouling. Adsorption isotherm was applied to calculate the isotherm parameters such as adsorption capacity (KF) and surface heterogeneity (1/n). The KF values increased about 3.7 times at pH 3.0, 1.5 times at pH 5.2, and 2.3 times at pH 9.0 compared to that at pH 7.0. The hydrophobic interaction by dissociation of dimer structure of β-lactoglobulin to monomer structure at acidic and alkaline conditions showed the greatly increasing of the amount of protein adsorption by the protein and membrane interaction which might form the strong and rigid protein layer on the polymeric membrane surface. The addition of salt reduced the protein adsorption on PES membrane because of the interactions between charged protein molecules and salt ions.