Our previous work has proposed an electrochemistry - total internal reflection imaging ellipsometry (EC-TIRIE) technique to observe the dissolved oxygen (DO) reduction on Clark electrode since high interface sensitivity makes TIRIE a useful tool to study redox reactions on the electrode surface. To amplify the optical signal noise ratio (OSNR), a surface tethered weak polyelectrolyte, carboxylated poly(oligo(ethylene glycol) methacrylate-random- 2-hydroxyethylmethacrylate) (abbreviated as carboxylated poly(OEGMA-r-HEMA)), has been introduced on the electrode surface. Since Clark electrode is widely used in biochemical oxygen demand (BOD) detection, we use this technique to measure BOD in the sample. The dynamic range of the system is from 0 ∼ 25 mg/L. Two samples have been measured. Compared with the conventional method, the deviation of both optical and electrical signals are less than 10%.

Date Published: 11 March 2015
PDF: 4 pages
Proc. SPIE 9336, Quantitative Phase Imaging, 93360C (11 March 2015); doi: 10.1117/12.2078486

Published in SPIE Proceedings Vol. 9336:
Quantitative Phase Imaging
Gabriel Popescu; YongKeun Park, Editor(s)