Sequential injection analysis system for on-line monitoring of l-cysteine concentration in biological processes.
A sequential injection analysis (SIA) system was developed to monitor the concentration of l-cysteine in biological processes on-line. It is based on the redox reaction of l-cysteine with iron(III) in the presence of 1,10-phenanthroline (phen) and the detection of the red-iron(II)-phen complex with a spectrophotometry. The system was fully automated using software written in the LabVIEWtrade mark development environment. A number of system variables such as the flow rate of the carrier buffer solution, the volume ratio of the sample to the reagents, and the reaction coil length, etc., were evaluated to increase the sensitivity and performance of the SIA system. Under partially optimized operating conditions the performance of the SIA system was linear up to a concentration of l-cysteine of 1mM (R(2)=0.998) with a detection limit of 0.005mM and a sample frequency of 15hr(-1). The SIA system was employed to monitor the concentration of l-cysteine on-line in a continuously stirred reactor and a fermentation process of Saccharomyces cerevisiae. The on-line monitored data were in good agreement with the off-line data measured by a HPLC with a fluorescence detector (n=15, R(2)=09899).
Lee
Seung-Hyun
SH
BioProcess Technology Laboratory, Chonnam National University, YongBong-dong 300, 500-757 Gwangju, Republic of Korea; Department of Materials and Biochemical Engineering, Chonnam National University, YongBong-dong 300, 500-757 Gwangju, Republic of Korea; Research Center for Biophotonics, Chonnam National University, YongBong-dong 300, 500-757 Gwangju, Republic of Korea.
Sohn
Ok-Jae
OJ
Yim
Yong-Sik
YS
Han
Kyung-Ah
KA
Hyung
Gi Woo
GW
Chough
Sung Hyo
SH
Rhee
Jong Il
JI