• Archives of Pharmacal Research
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• v.18 no.4
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• pp.231-236
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• 1995

Effects of sodium salts of various monovalent inorganic anions on transdermal permeation of salicylic acid were investigated. In in-vitro experiment using a Franz-type diffusion cell and excisicylic acid were investigated. In-vitro experiment using a Franze-type diffusion cell and excised mouse skin, the permeation-enhancing activities of the sodium salts of inoraganic anions were rougly proportional to lyotropic Hofmeister serlling abilities of the anions l F/sup -/

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.05a
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• pp.193-197
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• 2002

The tribological properties and van der Waals attractive forces and the thermal stability of films are very important characteristics of highly hydrophobic fluorocarbon (FC) films for the long-term reliability of nano system. The effect of thermal annealing on films and van der Waals attractive forces and friction coefficient of films have been investigate d in this study. It was coated Al wafer which was treated O2 and Ar that ocatfluorocyclobutane ($C_4_{8}$) and Ar were supplied to the CVD chamber in the ratio of 2:3 for deposition of FC Films. Static contact angle and dynamic contact angle were used to characterize FC films. Thickness of films was measured by variable angle spectroscopy ellipsometer (VASE). Nanotribological data was got by atomic force microscopy (AFM) to measure roughness, lateral force microscopy (LFM) to measure friction force, and force vs. distance (FD) curve to evaluate adhesion force. FC films were cured in N2 and vacuum. The film showed the slight changes in its properties after 3 hr annealing. FTIR ATR studies showed the decrease of C-F peak intensity in the spectra as the annealing time increased. A significant decrease of film thickness has been observed. The friction force of Al surface was at least thirty times higher than ones with FC films. The adhesive force of bare Al was greater than 100 nN. After deposit FC films adhesive force was decreased to 40 nN. The adhesive force of films was decreased down to 10 nN after 24 hr annealing. During 24 hr annealing in $N_2$and vacuum at $100^{\circ}C$ film properties were not changed so much.

• Nuclear Engineering and Technology
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• v.52 no.10
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• pp.2320-2327
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• 2020

The extreme hydrophobicity of expanded polytetrafluoroethylene (ePTFE) hinders bone-tissue integration, thus limiting the use of ePTFE in medical implant applications. To improve the potential of ePTFE as a biomaterial, 2-hydroxyethyl methacrylate (HEMA) was grafted onto the ePTFE surface using the gamma irradiation technique. The characteristics of the grafted ePTFE were successfully evaluated using attenuated total reflectance Fourier transform infrared (ATR-FTIR), field-emission scanning electron microscopy (FESEM)/energy dispersive X-ray (EDX), and X-ray photoelectron spectroscopy (XPS). Under the tensile test, the modified ePTFE was found to be more brittle and rigid than the untreated sample. In addition, the grafted ePTFE was less hydrophobic with a higher percentage of water uptake compared to the untreated ePTFE. The protein adsorption test showed that grafted ePTFE could adsorb protein, which was denoted by the presence of N peaks in the XPS analysis. Moreover, the formation of the globular mineral on the grafted ePTFE surface was successfully visualized using the FESEM analysis, with a ratio of 1.94 for Ca:P minerals by the EDX. To summarize, the capability of the modified ePTFE to show protein adsorption and mineralization indicates the improvement of the polymer properties, and it can potentially be used as a biomaterial for implant application.

• Journal of Radiation Industry
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• v.6 no.2
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• pp.159-164
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• 2012

Bacterial cellulose (BC) is generated from citrus gel by Gluconacetobacter hansenii TL-2C. BC has good properties such as high-burst pressure, high-water contact and the ultrafine highly nanofibrous structure of mimic natural extracellular matrix (ECM) for tissue engineering. In this study, acrylic acid (AAc) was grafted onto BC surfaces under aqueous conditions using gamma-ray irradiation, and then immobilized gelatin onto AAc-g-BC. The characterization of scaffolds was performed by scanning electron microscopy (SEM), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), toluidine blue O (TBO) assay. Morphology of gelatin and AAc incorporation onto BC nanofibers did not changed. Our study suggests that gelatin-immobilized BC nanofibers scaffold has a potentiality to fabricate 3D nanofibrous scaffolds for tissue engineering.

• Macromolecular Research
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• v.17 no.11
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• pp.850-855
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• 2009

Keratin is an important protein used in wound healing and tissue recovery. In this study, keratin was modified chemically with iodoacetic acid (IAA) to enhance its solubility in organic solvent. Poly(hydroxybutylate-co-hydroxyvalerate) (PHBV) and modified keratin were dissolved in hexafluoroisopropanol (HFIP) and electrospun to produce nanofibrous mats. The resulting mats were surface-characterized by ATR-FTIR, field-emission scanning electron microscopy (FE-SEM) and electron spectroscopy for chemical analysis (ESCA). The pure m-keratin mat was cross-linked with glutaraldehyde vapor to make it insoluble in water. The biodegradation test in vitro showed that the mats could be biodegraded by PHB depolymerase and trypsin aqueous solution. The results of the cell adhesion experiment showed that the NIH 3T3 cells adhered more to the PHBV/m-keratin nanofibrous mats than the PHBV film. The BrdU assay showed that the keratin and PHBV/m-keratin nanofibrous mats could accelerate the proliferation of fibroblast cells compared to the PHBV nanofibrous mats.

• Analytical Science and Technology
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• v.21 no.4
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• pp.326-331
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• 2008

Distribution coefficients (Kd) of uranyl ion onto divinylbenzene amidoxime resins were measured in sodium carbonate solution and the Kd values were increased up to about 70 as the resin bead size was decreased. At a condition of 0.0044 M $Na_2CO_3$, the adsorption capacity for uranium was $3.4{\mu}mole$ U/g-resin. The Kd values in the 0.5 M $Na_2CO_3-NaHCO_3$ solution, ranging from pH 9 to pH 11, revealed that they were increased as the pH increased and revealed lower values than those in the pure sodium carbonate solution. The amidoxime resins were characterized by FTIR-ATR showing the absorption bands of the amidoxime functional groups. A species of the uranyltricarbonate complex, $UO_2(CO_3)_3^{-4}$, was confirmed by UV-Vis spectroscopy, revealing four absorption peaks between 400 and 500 nm. Uranium was separated from some fission products by a column operation. However, most of the uranium and fission products were eluted before an adsorption and only a small amount of uranium was adsorbed onto the resin due to the low capacity of the resin.

• Applied Chemistry for Engineering
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• v.31 no.2
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• pp.220-225
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• 2020

Hair is made of proteins containing various amino acids. Ultraviolet (UV) radiation is believed to be responsible for the most damaging effects of sunlight, and also plays an important role in hair aging. The purpose of this study was to investigate the changes in morphological and chemical structures after ultraviolet B (UVB) irradiation of human hair. The UVB-irradiated hair showed characteristic morphological and structural changes, compared to those of the normal hair. The result from a scanning electron microscope (SEM) equipped with an energy dispersive X-ray diffractometer (EDX) showed that the scale of UV-irradiated hair appeared to be rough and the amount of oxygen element was higher than that of the normal hair. Fluorescence and three dimensional (3D) topographical images were obtained by a confocal laser scanning microscope (CLSM). In 3D images, the green emission intensity of normal hair was much higher than that of fluorescing UVB-irradiated hair. The intensity of green emission reflects the intrinsic fluorescence of hair protein. Also, a fluorescent imaging method using fluorescamine reagent was used to identify the free amino groups resulting from a peptide bond breakage in UVB-irradiated hair. Strong blue fluorescence of UVB-irradiated hair, which indicates a very high level of amino groups, was observed by CLSM. Therefore, the fluorescamine as an extrinsic fluorescence could provide a useful tool to identify the peptide bond breakage in UVB-irradiated hair. Infrared image mapping was also employed to assess the cross-sections of normal and UVB-irradiated specimens to examine the oxidation of disulfide bonds. The degree of peak areas with strong absorbance for the disulfide mono-oxide was spread from the outside to the inside of hair. The spectroscopic techniques used alone, or in combination, launch new possibilities in the field of hair cosmetics.

• Korean Journal of Heritage: History & Science
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• v.55 no.4
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• pp.166-177
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• 2022

The Shiveet Khairkhan is located on Tsengel Som in the middle of Bayan-ulgi Aimag in the Altai region. Various remains have been identified, and it has been found to be an important area of the Eurasian steppe. In this study, the characteristics of textile fibers and dyes excavated from the tombs of the 1st~3rd century Xianbei period in the sites of Shiveet Khairkhan, Mongolia were investigated. As a result of analysis using optical microscopic observation and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) for fiber identification, green and yellow fabrics were identified as silk fabrics. To investigate the properties of the dye, the surface reflectance of the dyed fabric was measured using an fiber optic reflectance spectrophotometer for non-destructive analysis. The green fabric appeared similar to the reflection spectrum of indigo dye. In addition, as a result of component analysis using gas chromatography-mass spectrometry, isatin and indigotine were detected. Isatin and indigotine are characteristic components of indigo dye, and it was found that the green fabric of the tombs of the Xianbei period was dyed using indigo dye. It was difficult to identify the type of dye in the yellow fabric as a result of reflectance spectrum and gas chromatography analysis. Indigo plants are a dye used for blue dyeing from thousands of years ago, and many species are distributed around the world. It was confirmed that the fabric was relatively well preserved and indigo dye was used for the green Jikryeongui (garment with a straight collar) in the ancient tomb of the Xianbei period about 1,800 years ago, even though it was buried for a long time. Scientific investigation of textile cultural heritage is an essential process for conservation treatment, restoration, exhibition, and the creation of a conservation environment. It is expected that related research will be activated in the future and will be helpful in interpreting the living culture at the time, preserving textiles, and a conservation environment.

• Korean Journal of Heritage: History & Science
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• v.56 no.3
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• pp.158-171
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• 2023

Pottery filled with organic materials was excavated from the G-2 building site of Yongjangseong Fortress, Jingo, a relic of the Goryeo Dynasty. In this study, the characteristics of organic material were confirmed by a scientific analysis of organic material in pottery found at the palace in Yongjangseong, Jindo. In addition, it was intended to review the analysis method to identify the natural resin and to secure characteristic components(biomarkers) for each natural resin and use them as basic data in the future. The organic materials in the pottery were analyzed using attenuated total reflectance Fourier-transformed infrared spectroscopy(ATR-FTIR) and gas chromatography mass spectrometry(GC-MS). The infrared spectral characteristics were estimated to be natural resin, and biomarkers of organic materials were identified as sesquiterpene-based compounds(C₁₅H₂₄, MW 204) and derivatives. The lacquer(T.vemicifluum) is composed mainly of alkenes, alkanes, and catechol. Pine resin(P.densiflora), on the other hand, is primarily composed of diterpenoid(abietic acid, pimaric acid) and Whangchil(yellow lacquer) is identified to have sesquiterpenes(such as selinene, muurolene, calamenene) as its main components. So, the organic material in the pottery can be identified as Whangchil by comparing their compounds with modern resin materials from Dendropanax. morbifera that correspond with the results. Whangchil, which is exuded from the Dendropanax. morbifera, has been used as a natural coating materials since ancient times, and it has been confirmed that the characteristic components are well preserved even 700 years later. It can be assumed that the interior Whangchil was stored not for use as a coating, but rather for ritual purposes when the building was constructed, because the pottery was found near the cornerstone. Furthermore, based on simplified sample preparation using pyrolysis-gas chromatography mass spectrometry(Py-GC-MS), the thermal decomposition products were found to be similar to the characteristic components, suggesting that this method can be applied to the identification of natural resins used in historic artifacts.