INVESTIGADORES
BORSARELLI Claudio Dario
congresos y reuniones científicas
Título:
Photoacoustic determination of the triplet energy of the carotenoid bixin in a photosensitized energy-transfer cascade
Autor/es:
A. DE O. RIOS; A. Z. MERCADANTE; C. D. BORSARELLI
Lugar:
Los Cocos, Cba., Argentina
Reunión:
Conferencia; 9TH LATIN AMERICAN CONFERENCE ON PHYSICAL ORGANIC CHEMISTRY; 2007
Institución organizadora:
UNC
Resumen:
The triplet state energy level of the natural cis carotenoid bixin (methyl hydrogen 9Z-6, 6-diapocarotene-6,6-dioate) was determined using laser-induced photoacoustic calorimetry (PAC) in acetonitrile/methanol (1:1) solution. An energy-transfer process with anthracene as sensitizer in O2-saturated solution was used to populate the carotenoid triplet state. The energy balance of the system allowed the calculation of the triplet energy content of bixin as ET = 18 kcal/mol. The result is discussed in relation with both its singlet molecular oxygen quenching and cis -->trans isomerization abilities. The quantum yield of 0.69 for the formation either of the triplet state or the singlet molecular oxygen by the sensitizer anthracene was also determined.
