title: LIF spectroscopy of stained malignant breast tissues.
abstract: We employ laser induced fluorescence (LIF) spectroscopy to discriminate between normal and cancerous human breast (in-vitro) tissues. LIF signals are usually enhanced by the exogenous agents such as Rhodamine 6G (Rd6G) and Coumarin 7 (C7). Although we observe fluorescence emissions in both fluorophores, Rd6G-stained tissues give notable spectral red shift in practice. The latter is a function of dye concentration embedded in tissues. We find that such red shifts have a strong dependence on the dye concentration in bare, in stained healthy, and in malignant breast tissues, signifying variations in tubular abundances. In fact, the heterogeneity of cancerous tissues is more prominent mainly due to their notable tubular densities- which can provide numerous micro-cavities to house more dye molecules. We show that this can be used to discriminate between the healthy and unhealthy specimens in different biological scaffolds of ordered (healthy) and disordered (cancerous) tissues. It is demonstrated that the quenching process of fluorophore' molecules slows down in the neoplastic tumors according to the micro-partitioning, too.
authors.affiliation: Physics Department, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran, Iran.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Ghasemi
authors.affiliation: Physics Department, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran, Iran.
authors.forename: Parviz
authors.initials: P
authors.lastname: Parvin
authors.affiliation: Physics Department, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran, Iran.
authors.forename: Najme Sadat Hosseini
authors.initials: NS
authors.lastname: Motlagh
authors.affiliation: Physics & Astronomy Department, California State University 90032, Los Angeles, California, USA.
authors.forename: Shahriar
authors.initials: S
authors.lastname: Abachi
keywords: (020.3690) Line shapes and shifts; (170.4580) Optical diagnostics for medicine; (170.6510) Spectroscopy, tissue diagnostics; (300.2530) Fluorescence, laser-induced