High-throughput assay of oxygen radical absorbance capacity (ORAC) using a multichannel liquid handling system coupled with a microplate fluorescence reader in 96-well format.
The oxygen radical absorbance capacity (ORAC) assay has been widely accepted as a standard tool to measure the antioxidant activity in the nutraceutical, pharmaceutical, and food industries. However, the ORAC assay has been criticized for a lack of accessibility due to the unavailability of the COBAS FARA II analyzer, an instrument discontinued by the manufacturer. In addition, the manual sample preparation is time-consuming and labor-intensive. The objective of this study was to develop a high-throughput instrument platform that can fully automate the ORAC assay procedure. The new instrument platform consists of a robotic eight-channel liquid handling system and a microplate fluorescence reader. By using the high-throughput platform, the efficiency of the assay is improved with at least a 10-fold increase in sample throughput over the current procedure. The mean of intra- and interday CVs was <or=15%, and the limit of detection and limit of quantitation were 5 and 6.25 microM, respectively.
Huang
Dejian
D
Brunswick Laboratories, 6 Thatcher Lane, Wareham, Massachusetts 02571, USA.
Ou
Boxin
B
Hampsch-Woodill
Maureen
M
Flanagan
Judith A
JA
Prior
Ronald L
RL
D001322:Autoanalysis / Q000379:methods*; D004355:Drug Stability; D005456:Fluorescent Dyes; D005609:Free Radicals / Q000032:analysis; D007202:Indicators and Reagents; D008027:Light; D017382:Reactive Oxygen Species / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000379:methods*
D005456:Fluorescent Dyes; D005609:Free Radicals; D007202:Indicators and Reagents; D017382:Reactive Oxygen Species