Nonlinear decomposition and two-photon fluorescence of molecules in sensitized tissues

Vladimir A. Hovanessian; Asatur A. Lalayan

doi:10.1117/12.273504

8 May 1997 Nonlinear decomposition and two-photon fluorescence of molecules in sensitized tissues

Vladimir A. Hovanessian, Asatur A. Lalayan

Proceedings Volume 2972, Optical Methods for Tumor Treatment and Detection: Mechanisms and Techniques in Photodynamic Therapy VI; (1997) https://doi.org/10.1117/12.273504
Event: BiOS '97, Part of Photonics West, 1997, San Jose, CA, United States

Abstract

Generation of reactive photoproducts from the chromophores and destruction of biomolecules can be realized with high efficiency if the irradiation of the solutionis carried out by an intensive laser radiation, when two-step light absorption and photoreactions from highly excited electronic states of molecules are taken place. We have observed nonlinear decomposition of sensitizers in tissues upon picosecond laser radiation by fluorescence method. The subsequent change of the autofluorescence spectra of sensitized tissues has ben observed. Fluorescence spectra of tissues sensitized by tumor-localizing sensitizers hematoporphyrin derivative (HpD) chlorin e₆ was registered using fiber-optic laser spectrofluorometer. It has been shown that initial rate of photobleaching is depended quadratically on the irradiation intensity. Two- photon excited fluorescence from tissues, sensitized by chlorin e(subscript 6$., and HpD has ben registered during excitation by picosecond YAG:Nd laser. These spectra coincided with that at one photon excitation, however, the background autofluorescence was absent. Red and near infrared radiation allows to increase the light penetration depth and as a result one can enhance the sensitivity of fluorescence diagnosis and the efficiency of photochemical treatment of tumors.

Citation Download Citation

Vladimir A. Hovanessian and Asatur A. Lalayan "Nonlinear decomposition and two-photon fluorescence of molecules in sensitized tissues", Proc. SPIE 2972, Optical Methods for Tumor Treatment and Detection: Mechanisms and Techniques in Photodynamic Therapy VI, (8 May 1997); https://doi.org/10.1117/12.273504

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
4 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Tissues

Luminescence

Picosecond phenomena

Absorption

Molecules

Tumors

Photodynamic therapy

Show All Keywords

Keywords/Phrases

Search In:

Publication Years