@article{oai:nagasaki-u.repo.nii.ac.jp:00012281,
 author = {Ahmed, Sameh and Kishikawa, Naoya and Ohyama, Kaname and Imazato, Takahiro and Ueki, Yukitaka and Kuroda, Naotaka},
 issue = {1},
 journal = {Talanta},
 month = {Jul},
 note = {Vitamin K is a fat-soluble vitamin involved in blood coagulation and bone metabolism. The detection and monitoring of vitamin K homologues in rheumatoid arthritis (RA) patients is a challenging problem due to the smaller concentrations of vitamin K and the presence of several interfering medications. Therefore, this study aimed to develop a new highly sensitive and selective chemiluminescence (CL) method designated to quantify vitamin K homologues in plasma of RA patients including phylloquinone (PK, vitamin K(1)), menaquinone-4 (MK-4, vitamin K(2)) and menaquinone-7 (MK-7, vitamin K(2)). The method was based on the unique photochemical properties of vitamin K homologues that were exploited for selective luminol CL reaction. The correlation coefficients of 0.998 or more were obtained in the concentration ranges of 0.1-100 ng mL(-1) vitamin K homologues. The detection limits were 0.03-0.1 ng mL(-1) in human plasma for vitamin K homologues. The developed HPLC-CL system was successfully applied for selective determination of vitamin K homologues in plasma of RA patients. The developed method may provide a useful tool for monitoring vitamin K homologues in different clinical studies such as RA, osteoporosis and hepatocellular carcinoma in which vitamin K is intervented., Talanta, 85(1), pp.230-236; 2011},
 pages = {230--236},
 title = {Selective chemiluminescence method for monitoring of vitamin K homologues in rheumatoid arthritis patients.},
 volume = {85},
 year = {2011}
}