DETERMINATION OF VITAMINS K 1 AND K3 IN COSMETICS 467 determination of deuterated vitamin K (phylloquinone) in human serum after ingestion of deuterium­ labeled broccoli,]. Nutr. Biochem., 13, 168-174 (2002). (5) M. Reta, M. E. Figueira, H. M. Felipe, and C. M. M. Almeida, Analysis of vitamin K in green tea leaves and infusions by SPME-GC-FID, Food Chem., 100, 405-411 (2007). (6) S. Odes and 0. Cagindi, Determination of vitamin K 1 content in olive oil, chard and human plasma by RP-HPLC method with UV-Vis detection, Food Chem., 100, 1220-1222 (2007). (7) V. I. Piironen, T. J. Koivu, 0. Tammisalo, and P. Mattila, Determination of phylloquinone in oils, margarines and butter by high-performance liquid chromatography with electrochemical detection, Food Chem., 59, 473-480 (1997). (8) T. J. Koivu-Tikkanen, V. Ollilainen, and V. I. Piironen, Determination of phylloquinone and mena­ quinones in animal products with fluorescence detection after postcolumn reduction with metallic zinc,]. Agric. Food Chem., 48, 6325-6331 (2000). (9) G. W. Chase, Jr., R.R. Eitenmiller, and A. R. Long, The liquid chromatographic analysis of vitamin K 1 in soy based infant formula using matrix solid phase dispersion,]. Liq. Chromatogr. Rel. Techn., 23, 423-432 (2000). (10) Y. Suhara, M. Kamao, N. Tsugawa, and T. Okano, Method for the determination of vitamin K homologues in human plasma using high-performance liquid chromatography-tandem mass spec­ trometry, Anal. Chem., 77, 757-763 (2005).

j. Cosmet. Sci. 1 59, 469--480 (November/December 2008) Determination and validation of six sunscreen agents in suncare products by UPLC and HPLC SO-MI LEE, HYE-JIN JEONG, and 1H SEOP CHANG, Amore Pacific Corporation, R&D Center, 314-1 Bora-dong, Giheung-gu, Yongin-si, Gyeonggi-do, 446-7 29 Korea. Synopsis Methylene bis-benzotriazolyl tetramethyl butylphenol and bis-ethylhexyloxy phenol methoxyphenyl tri­ azine are sunscreen agents that have hydrophobic behaviors in common. They were not normally assayed with the following four sunscreen agents that have hydrophilic behaviors in a single chromatographic run: ethylhexyl methoxycinnamate, isoamyl p-methoxycinnamate, ethylhexyl salicylate, and ethylhexyl triazone. For that reason, methylene bis-benzotriazolyl tetramethyl butylphenol and bis-ethylhexyloxy phenol me­ thoxyphenyl triazine require much time in order to assay products with those materials. A rapid, selective, and reproducible determination method needs to be developed for the simultaneous examination of methylene bis-benzotriazolyl tetramethyl butylphenol and bis-ethylhexyloxy phenol me­ thoxyphenyl triazine with the sunscreen agents, ethylhexyl methoxycinnamate, isoamyl p-methoxycinna­ mate, ethylhexyl salicylate, and ethylhexyl triazone. This new technique could reduce time in examining the sunscreen agents and be effective for quality control of suncare products. In this paper, the HPLC and UPLC system is used for developing the determination of the sunscreen agents. Several evaluations of some mixtures of eluents and columns were obtained for the optimal condition of separation. In HPLC, the optimal peak resolution was obtained through ethanol-water gradient elution and a 75-mm ClS column with a 3.5-µm-sized particle on a flow rate of 1.0 ml/min. In UPLC, the most distinctive peak resolution was obtained through methanol-water gradient elution and a 50-mm ClS column with a 1.7-µm-sized particle on a flow rate 0.4 ml/min. Both of those chromatographic determi­ nation methods could be used in the examination of six types of sunscreen agents without any interference from other product excipients in the agents. The proposed determination methods were validated for specificity, linearity, repeatability, system stability, intermediate precision, and accuracy. Consequently, HPLC and UPLC determination methods could be rapid, selective, and proper applications for the assay of sunscreen agents in suncare products. INTRODUCTION Solar radiation is recognized to be one of the major causes of skin cancer, photo-aging, and photodermatoses (1--4). There is an increasing need for strong sunscreen agents to prevent UV light's damaging effect on human skin. Chemical sunscreens are compounds that can absorb or reflect deleterious UV light. They can prevent or minimize the harmful effects of solar radiation on the skin. Address all correspondence to So-Mi Lee. 469