• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.4
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• pp.321-330
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• 2022

This study attempted to establish an optimal multi-compound simultaneous analysis method that can secure reliable results for 15 - preservatives, 2 - sun screens and 1 - antioxidants of cosmetics using HPLC-PDA. Since the potential of hydrogen (pH) in the mobile phase affects the acid dissociation constant (pKa) of the preservatives, and the peak retention time shift and area change were observed. The peak separation condition was established by adjusting the pH to 0.1% H₃PO₄ addition (mL) when preparing the mobile phase. As a results of method validation, the linearity correlation coefficient (R²) of above 0.999 were obtained, and accuracy 87.9 ~ 101.1%, 0.1 ~ 7.6% precision for two types of cosmetics (cream and shampoo). It was found that the limit of detection (LOD) was 0.1 ~ 0.2 mg/kg and the limit of quantitation (LOQ) was 2.0 ~ 4.0 mg/kg. In addition, it was possible to simultaneously separate p-anisic acid, a natural compound that was difficult to separate in HPLC due to the small difference from methylparaben, a synthetic preservatives. Through this study, it will be effectively used to secure quality control and safety for compound that need restrictions on use cosmetics.

• Journal of the Korean Applied Science and Technology
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• v.36 no.3
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• pp.915-929
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• 2019

This study attempted to investigate the effects of natural henna-treated permanent wave on degree of damage and morphological changes of hair. For this, amino acid was analyzed, and hair thickness and surface were observed through SEM. In addition, hair curl formation & retention, methylene blue coloring, tensile strength and elongation were measured. The results found the followings: Total amino acid contents rose as the number of natural henna treatment increased, hair protection effects are expected. In terms of curl formation, in an experimental group hair became more elastic as the number of natural henna treatment increased, compared to a control group. In both control and experimental groups, hair retention decreased as shampooing frequency increased because of extension of (C) and (C)', According to analysis of hair thickness using SEM, hair became thick in an experimental group after natural henna treatment, compared to a control group. In morphological observation of hair surface, it was mostly clean, and cuticle was tidy and healthy. In methylene blue coloring, as the number of natural henna treatment increased, absorbance went up. In addition, tensile strength declined in an experimental group, compared to a control group. As the number of natural henna treatment increased, elongation in an experimental group increased, compared to a control group. The above results show that as the number of natural henna treatment increased, hair became thicker, and curl formation and retention improved. In addition, hair elasticity and flexibility were enhanced, reducing a risk of hair damage. Therefore, the study results would be available as basic data in reducing scalp and hair damage, proposing the natural henna treatment as a method to reduce hair damage from chemical perm in cosmetology industry.

• Journal of Veterinary Clinics
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• v.20 no.2
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• pp.237-241
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• 2003

A case of juvenile onset generalized demodicosis of one year old, intact female Japanese Chin dog weighing 3.1kg was presented to the Small Animal Clinic of the College of Veterinary Medicine of Kyungpook National University. The diagnosis was made based on the physical examination, deep skin scrapings, hematology, serum chemistry, endocrinologic evaluation and bacterial culture. Numerous D. canis mites of various stages were observed in multiple skin scraping samples. CBC, serum chemistry, $T_3$, $T_4$ and free $T_4$ values were within normal range and Staphylococcus intermedius was isolated in bacterial culture of pustules. The dog was healthy other than skin lesions at the presentation. The three different treatment protocols were tried for the case. No clinical improvement was observed during 13 weeks of orally given daily basis ivermectin therapy at 600ug/kg and 2 weeks of spot-on weekly basis selamectin therapy at 30 mg/kg with cephalexin given orally twice a day at 25 mg/kg. However, a remarkable remission was seen by 0.1% amitraz dip on weekly basis with 4% chlorhexidine bath given twice a week. The secondary staphylococcal infection and accompanied pruritus was almost disappeared in two weeks and she was recovered clinically normal in 9 weeks of therapy. The therapy was continued for 4 more weeks to prevent relapse. The dog is clinically normal and being monitored for development of any abnormal dermatological signs for the time being.