Share Email Print

Proceedings Paper

Starch granules as a probe for the polarization at the sample plane of a high resolution multiphoton microscope
Author(s): Sotiris Psilodimitrakopoulos; Ivan Amat-Roldan; Susana Santos; Manoj Mathew; Anisha Thayil K. N.; Dobryna Zalvidea; David Artigas; Pablo Loza-Alvarez
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Because of its polarization sensitivity, SHG microscopy can provide information about the orientation and degree of structural organization inside biological samples. To fully exploit the above potential, the state of the polarization at the sample plane needs to be known. In this work we present starch granules as a reliable probe for the polarization state of the excitation beam at the sample plane of a high resolution multiphoton microscope. Polarization dependent SHG series of images demonstrated the radial distribution of SHG active molecules inside starch granules. This allowed the granule to exhibit symmetrical SHG emission regions. The pattern rotates along with the rotation of a λ/2 waveplate and thus, can demonstrate the polarization at the sample plane. Maximum signal in the forward detected geometry appears when imaging starch granules exactly at the hemisphere plane. Symmetric SHG regions rotating with the incoming linear polarization were also recorded in the backward detected geometry. A portion of the backwards detected SHG signal, which corresponds to two rotating equator arcs, does not overlap with the forward SHG signal. Importantly, polarization measurements, performed either in the forward or the backwards directions, have demonstrated the suitability and flexibility of this technique for both detection schemes. As result, observation of the starch signal allowed us to know the polarization of our SHG microscope. Furthermore, by coding this information in an angular representation, we corrected the input values in a theoretical model that predicts the average orientation of SHG active molecules. This has allowed us to map the mean orientation of SHG active molecules in body walls muscle of Caenorhabditis elegans, with pixel resolution.

Paper Details

Date Published: 12 March 2008
PDF: 11 pages
Proc. SPIE 6860, Multiphoton Microscopy in the Biomedical Sciences VIII, 68600E (12 March 2008); doi: 10.1117/12.763168
Show Author Affiliations
Sotiris Psilodimitrakopoulos, Institut de Ciències Fotòniques (Spain)
Ivan Amat-Roldan, Institut de Ciències Fotòniques (Spain)
Susana Santos, Institut de Ciències Fotòniques (Spain)
Manoj Mathew, Institut de Ciències Fotòniques (Spain)
Anisha Thayil K. N., Institut de Ciències Fotòniques (Spain)
Dobryna Zalvidea, Institut de Ciències Fotòniques (Spain)
David Artigas, Univ. Politècnica de Catalunya (Spain)
Pablo Loza-Alvarez, Institut de Ciències Fotòniques (Spain)

Published in SPIE Proceedings Vol. 6860:
Multiphoton Microscopy in the Biomedical Sciences VIII
Ammasi Periasamy; Peter T. C. So, Editor(s)

© SPIE. Terms of Use
Back to Top