Native Fluorescence Spectroscopy of Blood Plasma in the Characterization of Oral Malignancy¶

Abstract

Native fluorescence characteristics of blood plasma were studied in the visible spectral region, at two different excitation wavelengths, 405 and 420 nm, to discriminate patients with different stages of oral malignancy from healthy subjects. The fluorescence spectra of blood plasma of oral malignant subjects exhibit characteristic spectral differences with respect to normal subjects. Different ratios were calculated using the fluorescence intensity values at those emission wavelengths that give characteristic spectral features of each group of experimental subjects studied. These fluorescence intensity ratios were used as input variables for a multiple linear discriminant analysis across different groups. Leave-one out cross-validation was used to check the reliability of each discriminant analysis performed. The discriminant analysis performed across normal and oral cancerous subjects classified 94.7% of the original grouped cases and 93.7% of the cross-validated grouped cases. A classification algorithm was developed on the basis of the score of the discriminant functions (discriminant score) resulted in the analyses. The diagnostic potentiality of the present technique was also estimated in the discrimination of malignant subjects from normal and nonmalignant diseased subjects such as liver diseases. In the discriminant analysis performed across the three groups, normal, oral malignancy (including early and advanced stages) and liver diseases, 99% of the original grouped cases and 95.9% of the cross-validated grouped cases were correctly classified. Similar analysis performed across normal, early stage of oral malignancy, advanced oral malignancy and liver diseases correctly classified 94.9% of the original grouped cases and 91.8% of the cross-validated grouped cases.

Two-photon autofluorescence lifetime imaging of human skin papillary dermis in vivo: assessment of blood capillaries and structural proteins localization

“…Though the origin of these fluorophores requires further investigation, we note that at one-photon excitation in this wavelength region (~380 nm) numerous fluorophores are known to emit fluorescence in blood plasma, such as different advanced glycation end-products, NAD(P)H, fluorescent protein cross-links, etc. 60, 61 . However, the fast component of blood plasma decay (200 ± 20 ps) is sufficiently lower than that for NAD(P)H (~500 ps), which is known to contribute significantly to the blood plasma emission 62 .…”

“…However, the fast component of blood plasma decay (200 ± 20 ps) is sufficiently lower than that for NAD(P)H (~500 ps), which is known to contribute significantly to the blood plasma emission 62 . Fluorescence of biological liquids, especially of blood plasma, is extensively studied, that is motivated by the necessity to develop novel methods for the detection of pathologies and metabolic disorders in the human organism 60–62 . Collectively, our results suggest that TPEAF could be a prospective method to assess the fluorescence of blood plasma in vivo .…”

Rapid diagnosis and intraoperative margin assessment of human lung cancer with fluorescence lifetime imaging microscopy

“…The endogenous fluorophores in cells and tissues, such as reduced nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FAD), play a pivotal role in cellular energy metabolism [6], [7]. Compared to normal cells, many tumor cells have an increased metabolic demand and an elevated rate of aerobic glycolysis for rapid cell division [8].…”

Cancer diagnosis by autofluorescence of blood components

“…Kriegmair et al [16] and Malik et al [17] extended this work to the bladder cancer. Many studies followed the above work such as Weingandt et al [18], but only a few studies used this technique for diagnosis of cancer through serum or plasma [19][20][21][22][23][24].…”