The other reactions considered in the kinetic study were slow, and as a consequence, these reactions do not contribute to the photosensitizing capability of AMP.
Additionally, the calculations were performed to obtain the total rate constant for each type I and II mechanisms (ktypeI and ktypeII ) in the photosensitizing activity of AMP in lipid media, according to the next equations:
\(k_{\text{typeI}}=k_{Rxn20}\) (7)
\(k_{\text{typeII}}=k_{Rxn6}+k_{Rxn16}\) (8)
\(k_{\text{overall}}=k_{\text{typeI}}+k_{\text{typeII}}\) (9)
The overall reaction rate constants calculated from the equations above are shown in Table 4. It was observed that the type II mechanism was the fastest, and in the photosensitive capacity of AMP, this mechanism was preferred by 67.9 %. In contrast, the type I mechanism is carried out in 32.1%. AMP has a photosensitive capacity through both mechanisms; however, the primary mechanism on the photosensitizing ability of AMP in lipid media was type II. Finally, the overall reaction rate constant calculated on the photosensitizing capacity of AMP in lipid media was 2.79 x 1010 M−1s−1.
Table 4 : Reaction rate constants and branching ratios (Γ, %) of the photosensitizing capacity of AMP in lipid media, at 298 K.