The reactions of the pharmaceutical fluoxetine (FLX) with different radicals were investigated by pulse radiolysis. The reaction of hydroxyl radical (center dot OH) with FLX formed hydroxylated adduct of the aromatic ring, while oxidation of FLX by sulfate radical anion (SO4 center dot-) formed benzene radical cation that further reacted with H2O to yield the center dot OH adduct. The determined rate constants of center dot OH, hydrated electrons (e(aq)(-)), and SO4 center dot- with FLX were 7.8 x 10(9), 2.3 x 10(9), and 1.1 x 10(9) mol.L-1.s(-1), respectively. In the steady-state radiolysis study, the degradation of FLX in different radiolytic conditions by electron beam irradiation was detected by HPLC and UV-Vis spectra techniques. It was found that FLX concentration decreased by more than 90% in both N2O and air-saturated solutions after 1.5 kGy irradiation. In contrast, only 43% of FLX was decomposed in N-2-saturated solution containing 0.1 mol.L-1 tert-butanol. The degradation rates of FLX in acidic and neutral solutions were higher than those in alkaline solutions. Our results showed that the degradation of FLX is optimal in air-saturated neutral solution, and center dot OH-induced degradation is more efficient than SO4 center dot- oxidation of FLX. The obtained kinetic data and optimal conditions give some hints to understand the degradation of FLX.
Ji, TY,Liu, YC,Zhao, JF,et al. Radical-Induced Degradation of Fluoxetine in Aqueous Solution by Pulse and Steady-State Radiolysis Studies[J]. ACTA PHYSICO-CHIMICA SINICA,2017-01-01,33(4):823-828.
