Abstract
The technique of nanosecond pulse radiolysis has been used to study the one-electron reduction of toluidine blue. Apart from H ande aq − various organic reducing radicals derived from isopropanol, tetrahydrofuran, cytosine etc. have been employed. The rate constants for the one-electron reduction was evaluated from build up traces. By monitoring the absorbance changes as a function of pH, twopK a values were obtained suggesting the existence of the species in three conjugate acid-base forms. The spectra of the different protonated forms were monitored and their characteristic features have been presented here. In the case of H-atoms it has been observed that in addition to the electron-transfer reaction, other processes like adduct formation also appear to be taking place. Using the redox titration method, with radicals of known redox potential the one-electron reduction potential of toluidine blue was also evaluated (vs. NHE).
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References
Chiorboli C, Indelli M T, Scandola M A R and Scandola F 1988J. Phys. Chem. 92 156
Fielden E M 1984 inThe study of fast processes and transient species by electron pulse radiolysis (eds) J H Baxendale and F Busi (Boston: D. Reidel) p. 59
Guha S N, Moorthy P N and Rao K N 1979Mol. Photochem. 9 183
Guha S N, Moorthy P N, Kishore K, Naik D B and Rao K N 1987Proc. Indian Acad. Sci (Chem. Sci.) 99 261
Hatchard C G and Parker C A 1961Trans. Faraday Soc. 57 1093
Kamat P V, Karkhanavala M D and Moorthy P N 1979Indian J. Chem. A18 206, 210
Kamat P V and Lichtin N N 1982J. Photochem. 18 197
Keene J P, Land E J and Swallow A J 1965 inPulse radiolysis (eds) M Ebert, J P Keene, A J Swallow and J H Baxendale (New York: Academic Press) p. 227
Merrill R C and Spencer R W 1948J. Am. Chem. Soc. 70 3683
Nikolskii B P and Palchevskii V V 1958Zh. Fiz. Khim. 32 1280, cited by W M Clarke 1972 inOxidation-reduction potentials of organic systems (New York: R E Kreiger) p. 422
Rabinowitch E 1940J. Chem. Phys. 8 551, 560
Solar S, Solar W and Getoff N 1982Radial. Phys. Chem. 20 165
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Mahadevan, J., Guha, S.N., Kishore, K. et al. One-electron reduction of toluidine blue. A pulse radiolysis study. Proc. Indian Acad. Sci. (Chem. Sci.) 101, 43–53 (1989). https://doi.org/10.1007/BF02869385
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DOI: https://doi.org/10.1007/BF02869385