Open AccessPhotoacoustic measurement of refractive index of dye solutions and myoglobin for biosensing applications
Author(s) -
Benjamin Goldschmidt,
Smit Mehta,
Jeff Mosley,
Christian Walter,
Paul J. D. Whiteside,
Heather K. Hunt,
John A. Viator
Publication year - 2013
Publication title -
biomedical optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.362
H-Index - 86
ISSN - 2156-7085
DOI - 10.1364/boe.4.002463
Subject(s) - refractometer , refractive index , refractometry , materials science , reflectometry , optics , photoacoustic imaging in biomedicine , ellipsometry , optoelectronics , nanotechnology , computer science , thin film , time domain , physics , computer vision
Current methods of determining the refractive index of chemicals and materials, such as ellipsometry and reflectometry, are limited by their inability to analyze highly absorbing or highly transparent materials, as well as the required prior knowledge of the sample thickness and estimated refractive index. Here, we present a method of determining the refractive index of solutions using the photoacoustic effect. We show that a photoacoustic refractometer can analyze highly absorbing dye samples to within 0.006 refractive index units of a handheld optical refractometer. Further, we use myoglobin, an early non-invasive biomarker for malignant hyperthermia, as a proof of concept that this technique is applicable for use as a medical diagnostic. Comparison of the speed, cost, simplicity, and accuracy of the techniques shows that this photoacoustic method is well-suited for optically complex systems.