Photothermal optical coherence tomography of epidermal growth factor receptor in live cells using immunotargeted gold nanospheres

Melissa C. Skala; Matthew J. Crow; Adam Wax; Joseph A. Izatt

doi:10.1117/12.808052

19 February 2009 Photothermal optical coherence tomography of epidermal growth factor receptor in live cells using immunotargeted gold nanospheres

Melissa C. Skala, Matthew J. Crow, Adam Wax, Joseph A. Izatt

Author Affiliations +

Proceedings Volume 7168, Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XIII; 71680S (2009) https://doi.org/10.1117/12.808052
Event: SPIE BiOS, 2009, San Jose, California, United States

Abstract

Molecular imaging is a powerful tool for investigating disease processes and potential therapies in both in vivo and in vitro systems. However, high resolution molecular imaging has been limited to relatively shallow penetration depths that can be accessed with microscopy. Optical coherence tomography (OCT) is an optical analogue to ultrasound with relatively good penetration depth (1-2 mm) and resolution (~1-10 μm). We have developed and characterized photothermal OCT as a molecular contrast mechanism that allows for high resolution molecular imaging at deeper penetration depths than microscopy. Our photothermal system consists of an amplitude-modulated heating beam that spatially overlaps with the focused spot of the sample arm of a spectral-domain OCT microscope. Validation experiments in tissue-like phantoms containing gold nanospheres that absorb at 532 nm revealed a sensitivity of 14 parts per million nanospheres (weight/weight) in a tissue-like environment. The nanospheres were then conjugated to anti-EGFR, and molecular targeting was confirmed in cells that over-express EGFR (MDA-MB-468) and cells that express low levels of EGFR (MDA-MB-435). Molecular imaging in three-dimensional tissue constructs was confirmed with a significantly lower photothermal signal (p<0.0001) from the constructs composed of cells that express low levels of EGFR compared to the over-expressing cell constructs (300% signal increase). This technique could potentially augment confocal and multiphoton microscopy as a method for deep-tissue, depth-resolved molecular imaging with relatively high resolution and target sensitivity, without photobleaching or cytotoxicity.

Citation Download Citation

Melissa C. Skala, Matthew J. Crow, Adam Wax, and Joseph A. Izatt "Photothermal optical coherence tomography of epidermal growth factor receptor in live cells using immunotargeted gold nanospheres", Proc. SPIE 7168, Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XIII, 71680S (19 February 2009); https://doi.org/10.1117/12.808052

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