عنوان المقالة:Stability of Anticancer Drug 5-Fluorouracil in Aqueous Solution: An Assessment of Kinetic Behavior Stability of Anticancer Drug 5-Fluorouracil in Aqueous Solution: An Assessment of Kinetic Behavior
Spectroscopic measurements of pharmaceutical compound 5-fluorouracil (5-FU) drug was achieved
in solvents with different polarity. The drug gave clear absorption peak at 259, 269, 270 and 266 nm
in hexane, dimethyl sulfoxide (DMSO), N, N-dimethylformamide (DMF) and ethanol, as well as
phosphate buffer respectively, which was consistent with the standard values in literatures. The results
of extension coefficient (ε) and wave length (λmax) showed reduction in polar medium as compared to
non-polar medium. The calibration curve of 5-FU drug was achieved by using serials solutions dis-
solved in phosphate buffer (pH = 7.4 and T = 37 °C) within the range of 1×10– 6 ~ 1×10– 4 M. The sta-
bility of 5-FU drug was studied in phosphate buffer at pH = 5, 6, 7, 7.4 and 8 with 1×10– 5 M and T = 37 °C,
according to the equation of first-order reaction. The hydrolysis of 5-FU disappeared at alkaline solu-
tion, but had noticeable hydrolysis in acidic solutions with the rate constant 25, 14 and 20 at pH of 5,
6 and 7 respectively. The calculation of molar extension coefficient and half-life (t1/2) showed same
sequence of 5-FU hydrolysis. Then, rearrangement of obtained results offered complicated reversible
equilibrium state by the combination between thermodynamic and kinetic behaviors of 5-FU hydro-
lysis; with Keq = 8.46, 6.11 and 142.8 at pH of 5, 6 and 7 respectively. The acidic hydrolysis of 5-FU
occurred spontaneously within free energy (ΔG) did not exceed 10 kJ/mol, which meant the electro
motive forces of interactions were weak, notable to release energy such as Van der Waals forces or
hydrogen bonding
الملخص الانجليزي
Spectroscopic measurements of pharmaceutical compound 5-fluorouracil (5-FU) drug was achieved
in solvents with different polarity. The drug gave clear absorption peak at 259, 269, 270 and 266 nm
in hexane, dimethyl sulfoxide (DMSO), N, N-dimethylformamide (DMF) and ethanol, as well as
phosphate buffer respectively, which was consistent with the standard values in literatures. The results
of extension coefficient (ε) and wave length (λmax) showed reduction in polar medium as compared to
non-polar medium. The calibration curve of 5-FU drug was achieved by using serials solutions dis-
solved in phosphate buffer (pH = 7.4 and T = 37 °C) within the range of 1×10– 6 ~ 1×10– 4 M. The sta-
bility of 5-FU drug was studied in phosphate buffer at pH = 5, 6, 7, 7.4 and 8 with 1×10– 5 M and T = 37 °C,
according to the equation of first-order reaction. The hydrolysis of 5-FU disappeared at alkaline solu-
tion, but had noticeable hydrolysis in acidic solutions with the rate constant 25, 14 and 20 at pH of 5,
6 and 7 respectively. The calculation of molar extension coefficient and half-life (t1/2) showed same
sequence of 5-FU hydrolysis. Then, rearrangement of obtained results offered complicated reversible
equilibrium state by the combination between thermodynamic and kinetic behaviors of 5-FU hydro-
lysis; with Keq = 8.46, 6.11 and 142.8 at pH of 5, 6 and 7 respectively. The acidic hydrolysis of 5-FU
occurred spontaneously within free energy (ΔG) did not exceed 10 kJ/mol, which meant the electro
motive forces of interactions were weak, notable to release energy such as Van der Waals forces or
hydrogen bonding