SICCHIERI, LETICIA B.SILVA, MONICA N. daSAMAD, RICARDO E.COURROL, LILIA C.2018-04-182018-04-182018SICCHIERI, LETICIA B.; SILVA, MONICA N. da; SAMAD, RICARDO E.; COURROL, LILIA C. Can measurement of the fluorescence lifetime of extracted blood PPIX predict atherosclerosis?. <b>Journal of Luminescence</b>, v. 195, p. 176-180, 2018. DOI: <a href="https://dx.doi.org/10.1016/j.jlumin.2017.11.014">10.1016/j.jlumin.2017.11.014</a>. Disponível em: http://repositorio.ipen.br/handle/123456789/28855.0022-2313http://repositorio.ipen.br/handle/123456789/28855In this work, fluorescence lifetime has been used to analyze protoporphyrin IX (PPIX) extracted from blood for diagnosing atherosclerosis. A total of 10 adult white male rabbits (New Zealand) were divided into the control group (CG), with a normal diet, and the experimental group (EG), subjected to a diet containing 1% cholesterol. Blood samples were collected from the animals, and protoporphyrin IX was extracted from the blood using acetone. The PPIX fluorescence lifetime (PPIXFL) was measured using time-correlated single photon counting, after excitation at 403 nm from a pulsed laser diode. It was found that the PPIX emission intensity was enhanced in the animals that had received a hypercholesterolemic diet. The CG and EG animal's fluorescence decays were fitted by three exponentials and the mean lifetimes were 4.0 ns and 9.5 ns, respectively. This lifetime dependence resulted in a calibration curve that allows the determination of the PPIX concentration with a temporal measurement. The obtained results show that fluorescence lifetime can potentially be used as a noninvasive, simple, rapid, and sensitive tool in atherosclerosis diagnosis.176-180openAccessarteriosclerosisprotoporphyrinsfluorescence spectroscopybloodbioassaylifetimediagnostic usesdiagnosisArtigo de periódico19510.1016/j.jlumin.2017.11.014https://orcid.org/0000-0001-7762-896173.1673.60