Application of ring down measurement approach to micro-cavities for bio-sensing applications

M. Imran Cheema; Andrew G. Kirk

doi:10.1117/12.874890

8 February 2011 Application of ring down measurement approach to micro-cavities for bio-sensing applications

M. Imran Cheema, Andrew G. Kirk

Proceedings Volume 7888, Frontiers in Biological Detection: From Nanosensors to Systems III; 788808 (2011) https://doi.org/10.1117/12.874890
Event: SPIE BiOS, 2011, San Francisco, California, United States

Abstract

Optical biosensors can detect biomarkers in the blood serum caused by either infections or exposure to toxins. Until now, most work on the micro-cavity biosensors has been based on measurement of the resonant frequency shift induced by binding of biomarkers to a cavity. However, frequency domain measurements are not precise for such high Q micro-cavities. We hypothesize that more accurate measurements and better noise tolerance can be achieved by the application of the ring down measurement approach to the micro-cavity in a biosensor. To test our hypothesis, we have developed a full vectorial finite element model of a silica toroidal micro-cavity immersed in water. Our modeling results show that a toroidal cavity with a major diameter of 70μm and a minor diameter of 6μm can achieve a sensitivity of 28.6μs/RIU refractive index units (RIU) at 580nm. Therefore, our sensor would achieve the resolution of 5 x 10^-8 RIU by employing a detector with picosecond resolution. Hence we propose a micro-cavity ring down biosensor with high sensitivity which will find wide applications in real time and label free bio-sensing.

Citation Download Citation

M. Imran Cheema and Andrew G. Kirk "Application of ring down measurement approach to micro-cavities for bio-sensing applications", Proc. SPIE 7888, Frontiers in Biological Detection: From Nanosensors to Systems III, 788808 (8 February 2011); https://doi.org/10.1117/12.874890

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