Intracameral and lenticular penetration of locally applied stable isotope-labeled vitamin E.

PURPOSE To confirm the aqueous humor and lens dynamics of 1% deuterium-labeled alpha-tocopherol acetate (D(3)-VEA) solution. METHODS The concentrations of D(3)-VEA and D(3)-alpha-tocopherol (D(3)-VE), derived from D(3)-VEA, in the aqueous humor and lens were measured after continuous instillation of 1% D(3)-VEA into the cul-de-sac of rat eyes for 1 or 3 weeks. D(3)-VEA and D(3)-VE concentrations were determined by gas chromatography/mass selective detector. RESULTS In the aqueous humor, the concentrations of D(3)-VEA and D(3)-VE were, respectively, 93.1 and 9.4 ng/mL after 1 week, and, respectively, 498.9 and 21.5 ng/mL after 3 weeks. In the lens, they were, respectively, 15.0 and 9.8 ng/g after 1 week, and 6.1 and 4.8 ng/g after 3 weeks. CONCLUSION The penetration levels of alpha-tocopherol acetate by eyedrop application were confirmed in the aqueous humor and lens.