Degradation of estrogen conjugates using titanium dioxide as a photocatalyst.
Estrogen conjugates (estradiol-3-glucuronide, -17-glucuronide, estrone-glucuronide and -sulfate) were subjected to photodegradation using titanium dioxide immobilized on glass beads as a catalyst. Their time courses were measured by HPLC and compared with those of the unconjugated estrogens. Estradiol, its 17-glucuronide and estrone, which have an unconjugated phenolic hydroxy group at the C-3 position, were almost completely degraded by UV irradiation within 4 h. On the other hand, significant amounts of estradiol- and estrone-3-glucuronide (ca. 20%, 25%) and estrone sulfate (ca. 90%), which were conjugated at the 3-hydroxy group, remained after a 6.5 h irradiation. These results supported the hypothesis that the photodegradation of estrogens was initiated at the phenolic hydroxy group.
Mitamura
Kuniko
K
Faculty of Pharmaceutical Sciences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan. mitamura@p.kanazawa-u.ac.jp
Narukawa
Hitomi
H
Mizuguchi
Tatsuhito
T
Shimada
Kazutake
K
D002384:Catalysis; D002851:Chromatography, High Pressure Liquid; D004967:Estrogens / Q000737:chemistry*; D010777:Photochemistry; D014025:Titanium / Q000737:chemistry*
D004967:Estrogens; C009495:titanium dioxide; D014025:Titanium