• Journal of the Society of Cosmetic Scientists of Korea
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• v.22 no.1
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• pp.84-101
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• 1996

To minimize the use of animals in toxicity testing, and to reduce the cost in vivo test, more rational test method was described which determines, in the same animal, photoxic and photoallergic potential of a substance, and is daptable to routine testing. The other purpose of this study was to investigate the usefulness of in vivo alternatives ; photostability and spectrophotometric carbonyl assay. In this modified photosensitization model, animal numbers and resting periods, the number and method of topical application were simplified. Two positive photoreactive agents, Benzocaine and 6-methyl coumarine, showed a similar photoallergic potential to that of Ichikawa's method. Two sunscreens, Octyl methoxy cinnamate, Butyl methoxyl dibenzoyl methane, hardly showed photoallergic potentials. The photostability test could be used in the step of prescreening of photosensitization potential because most of the photoreactive agents represented the reduction of more than 20% in the absorbance. And photoreactive agents have a high potential of photosensitization in the sddessment of spectrophotometric carbonyl level although two sunscreens have a low possibility of photosensitization. Therefore this method was assumed as a valuable in vivo alternatives in the respect even in the very low concentrations which phototoxicity test using almonella showed no phototoxic potential.

• Korean Journal of Veterinary Pathology
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• v.1 no.1
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• pp.40-45
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• 1997

The phototoxic potentials of LB20304a a new quinolone compound being developed by LG Chemical Ltd, and reference compounds (Ciprofloxacin; CPFX, Enoxacin; ENX and Lomefloxacin; LFLX) were compared in a murine model. in addition photostability of these compunds was studied after irradiation with long-wave UV light(UVA, 0, 0.3 1 or 3 Joule/$Cm^2$) When hairless mice(9 to 11 weeks old 19-26g) were orally administered with different dose levels of test compunds and exposed to UVA(40J/$cm^2$) inflammatory reactions were observed in a dose dependent manner. Among the compounds tested, LB20304a demonstrated the least phototoxic effects and showed no inflammatroy lesions at a dose level of 100mg.kg (Low dose). ENX and LFLX demonstrated much greater phototoxic reactions while CPFX showed similar or slightly greater phototoxic reactions compared to LB20304a. Similar to the in-vivo results the solutions of LB20304a and CPFX irradiated with UVA demonstrated reduced spectral changes compared to those of ENX and LFLX. In conclusion these data suggest that phototoxic potencies of the quinolones tested were; LFLX > ENX > CPFX $\geq$ LB20304a. No phototoxic dose of LB20304a in mice was 100 mg/kg.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.45 no.2
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• pp.139-150
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• 2019

This study is investigated sunscreen formulation that enhances UV absorption efficiency by UV light. Ethylhexyl methoxycinnamate (OMC) is one of the most common UV filters. Many studies have been conducted about photostability of OMC. It is well known that under the UV exposure, trans-OMC could turn to cis-OMC, or produce various photoproducts including its dimers. Those chemical structure changes were understood as the reason of a decrease in UV absorption efficiency upon UV exposure. However, it was found that OMC and isoamyl p-methoxycinnamate (IMC) could even enhance its UV absorption efficiency when it was exposed to UV light in an environment similar to actual use. In order to develop sunscreen formulation that enhances UV absorption efficiency by UV light, emollient with high polarity and compatibility should be avoided from the formular. Those emollient seemed to prevent OMC or IMC from producing photoproducts under UV light. Finally, a sunscreen formulation (UV sensing SPF boosting formular) enhancing UV absorption efficiency by UV was developed by the UV activated SPF boosting technology, and the effect of the sunscreen was evaluated. in vitro SPF of the sunscreen was increased from 50.69 to 72.33 when it was exposed to UV light and its in vivo SPF (53.7) was 56.10% higher than that of the control sunscreen (below 34.4).