Primary photoprocesses in retinol

✍ Scribed by Tchiya Rosenfeld; Aron Alchalal; Michael Ottolenghi

• Book ID: 103014965
• Publisher: Elsevier Science
• Year: 1973
• Tongue: English
• Weight: 644 KB
• Volume: 20
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(73)85179-6

✦ Synopsis

Pulsed laser photolysis techniques, with nanosecond time-resolution, are applied to solutions of retinal ftitamin A) and retinyl acetate, under varying conditions of solvent polarity and oxygen content. Tbc observed absorkmce and conductivity changes are identified as due to: (a) the excited fluorescent state, hax = 435 nm; (b) the towest escited tripiet state, h,, = 40.5 nm; (c) the retinylic cation (kmas = 590 rim), formed via: ROH k RC f OH-. The results constitute the first e~perimentai evidence for ionic photodi~sociat~on and for spontaneous, as weti as osygeninduced, intcrsystem crossing in retinol. Both processes may provide routes for isomerizstion, being thus relevant to the \lisunl process.