Infrared free-electron-laser ablation of cholesterol esters in an arteriosclerotic region

Kunio Awazu; Yuko Fukami

doi:10.1117/12.350977

22 June 1999 Infrared free-electron-laser ablation of cholesterol esters in an arteriosclerotic region

Kunio Awazu, Yuko Fukami

Proceedings Volume 3590, Lasers in Surgery: Advanced Characterization, Therapeutics, and Systems IX; (1999) https://doi.org/10.1117/12.350977
Event: BiOS '99 International Biomedical Optics Symposium, 1999, San Jose, CA, United States

Abstract

Successful removal of cholesterol ester which is specifically accumulated in the arteriosclerotic region on the arterial walls was achieved by the exposure of 5.75 μm-IR free-electron-lasers (FEL) which is absorbed by C=O stretching vibrations of ester. In this study, chemical bond-changes and decrease in amount of cholesteryl oleate in IRFEL photodynamic processes were examined by Fourier transform IR microspectroscopy (FTIR). We found that the exposure of 5.75μm-FELs induces not only dissociation of ester (RCOOR') bonds but also the oxidation process of the ester (RCOOR') bonds to aldehyde (RCHO) carboxylic acid (RCHOOH), carboxylate (RCOO^-) or ketone (R₂C=O) bonds. Further, we exposed cholesteryl oleate to FELs having wavelength of 5.75μm, 9.40μm and 8.44μm. From changes in absorbance and thickness of the samples, we calculated quantum efficiency Φ for decrease of ester bonds and C-C chains for each wavelength-FEL exposure. Φ was obtained to be 2.1 X 10^-4 for ester bond and 1.2 X 10^-4 for C-C chain by 5.75μm-FELs, 0.9x10^-4 and 2.0x10^-4 by 9.40μm- FELs, and 1.2x10^-4 and 1.0x10^-4 by 8.44μm-FELs. Thus, we can conclude that removal of cholesteryl oleate by IR-FELs has the wavelength sensitivity coming from correspondence between the bonds which absorbs FEL photons and which aimed to remove.

Citation Download Citation

Kunio Awazu and Yuko Fukami "Infrared free-electron-laser ablation of cholesterol esters in an arteriosclerotic region", Proc. SPIE 3590, Lasers in Surgery: Advanced Characterization, Therapeutics, and Systems IX, (22 June 1999); https://doi.org/10.1117/12.350977

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
8 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Free electron lasers

Absorbance

Quantum efficiency

Absorption

Photons

FT-IR spectroscopy

Infrared radiation

Show All Keywords

Keywords/Phrases

Search In:

Publication Years