Light-induced electron transfer from a lipid-soluble zinc(II) porphyrin to various electron acceptors in frozen vesicle solutions: Effects of cholesterol on the solubilization sites and radical yields

Journal Article · Thu Jun 29 04:00:00 EDT 1989 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100350a047· OSTI ID:7197217

Lanot, M; Kevan, L ^[1]

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1. Univ. of Houston, TX (USA)

The photoionization of zinc tetraphenylporphyrin (ZnTPP) has been studied by electron spin resonance (ESR) at 77 K in rapidly frozen dipalmitoylphosphatidylcholine (DPPC) vesicle solutions, and in the presence of various electron acceptors like tetrachloro- and tetrabromobenzoquinone (TCBQ and TBBQ) and potassium ferricyanide (K{sub 3}Fe(CN){sub 6}). The photoproduced ZnTPP{sup +} yield was found to increase, and photoinduced anion formation was also detected for added tetrahalobenzoquinones. Incorporation of cholesterol in these systems altered the ZnTPP{sup +} radical yields via 2 main structural changes: (1) ZnTPP-water contact increased due to intercalation of cholesterol between the surfactant headgroups, and (2) TCBQ moved deeper into the vesicle bilayer because of increased bilayer fluidity.

• OSTI ID: 7197217
• Journal Information: Journal of Physical Chemistry; (USA), Journal Name: Journal of Physical Chemistry; (USA) Vol. 93:13; ISSN 0022-3654; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

25 ENERGY STORAGE
250800 -- Energy Storage-- Chemical
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400000* -- Chemistry
400500 -- Photochemistry
CARBOXYLIC ACIDS
CHOLESTEROL
DATA
DATA ANALYSIS
ELECTRON TRANSFER
ENERGY STORAGE
EXPERIMENTAL DATA
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
HYDROXY COMPOUNDS
INFORMATION
IONIZATION
LOW TEMPERATURE
MEASURING INSTRUMENTS
MEASURING METHODS
NUMERICAL DATA
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PHOTOIONIZATION
PORPHYRINS
STEROIDS
STEROLS
STORAGE