title: Sensing cell metabolism by time-resolved autofluorescence.
abstract: We built a time-resolved confocal fluorescence spectroscopy system equipped with the multichannel time-correlated single-photon-counting technique. The instrument provides a unique approach to study the fluorescence sensing of cell metabolism via analysis of the wavelength- and time-resolved intracellular autofluorescence. The experiments on monolayered cell cultures show that with UV excitation at 365 nm the time-resolved autofluorescence decays, dominated by free-bound reduced nicotinamide adenine dinucleotide signals, are sensitive indicators for cell metabolism. However, the sensitivity decreases with the increase of excitation wavelength possibly due to the interference from free-bound flavin adenine dinucleotide fluorescence. The results demonstrate that time-resolved autofluorescence can be potentially used as an important contrast mechanism to detect epithelial precancer.
authors.affiliation: Department of Electronic and Computer Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
authors.forename: Yicong
authors.initials: Y
authors.lastname: Wu
authors.forename: Wei
authors.initials: W
authors.lastname: Zheng
authors.forename: Jianan Y
authors.initials: JY
authors.lastname: Qu
mesh_terms: D002461:Cell Line, Transformed; D002478:Cells, Cultured; D005260:Female; D005182:Flavin-Adenine Dinucleotide / Q000378:metabolism; D005453:Fluorescence; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D018613:Microscopy, Confocal; D009243:NAD / Q000378:metabolism; D013050:Spectrometry, Fluorescence; D002583:Uterine Cervical Neoplasms / Q000378:metabolism*
chemical_list: D009243:NAD; D005182:Flavin-Adenine Dinucleotide; D007770:L-Lactate Dehydrogenase