Optoelectronic tweezers for the measurement of the relative stiffness of erythrocytes

Steven L. Neale; Nimesh Mody; Colin Selman; Jonathan M. Cooper

doi:10.1117/12.928839

10 October 2012 Optoelectronic tweezers for the measurement of the relative stiffness of erythrocytes

Steven L. Neale, Nimesh Mody, Colin Selman, Jonathan M. Cooper

Proceedings Volume 8458, Optical Trapping and Optical Micromanipulation IX; 845827 (2012) https://doi.org/10.1117/12.928839
Event: SPIE NanoScience + Engineering, 2012, San Diego, California, United States

Abstract

In this paper we describe the first use of Optoelectronic Tweezers (OET), an optically controlled micromanipulation method, to measure the relative stiffness of erythrocytes in mice. Cell stiffness is an important measure of cell health and in the case of erythrocytes, the most elastic cells in the body, an increase in cell stiffness can indicate pathologies such as type II diabetes mellitus or hypertension (high blood pressure). OET uses a photoconductive device to convert an optical pattern into and electrical pattern. The electrical fields will create a dipole within any polarisable particles in the device, such as cells, and non-uniformities of the field can be used to place unequal forces onto each side of the dipole thus moving the particle. In areas of the device where there are no field gradients, areas of constant illumination, the force on each side of the dipole will be equal, keeping the cell stationary, but as there are opposing forces on each side of the cell it will be stretched. The force each cell will experience will differ slightly so the stretching will depend on the cells polarisability as well as its stiffness. Because of this a relative stiffness rather than absolute stiffness is measured. We show that with standard conditions (20Vpp, 1.5MHz, 10mSm-1 medium conductivity) the cell’s diameter changes by around 10% for healthy mouse erythrocytes and we show that due to the low light intensities required for OET, relative to conventional optical tweezers, multiple cells can be measured simultaneously.

Citation Download Citation

Steven L. Neale, Nimesh Mody, Colin Selman, and Jonathan M. Cooper "Optoelectronic tweezers for the measurement of the relative stiffness of erythrocytes", Proc. SPIE 8458, Optical Trapping and Optical Micromanipulation IX, 845827 (10 October 2012); https://doi.org/10.1117/12.928839

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