An automated sequential injection analysis (SIA) system using stop-flow technique was developed to determine methanol concentration by means of the enzymatic reactions of alcohol oxidase and peroxidase. Its application as an on-line device for monitoring Pichia pastoris fermentations producing an heterologous protein was demonstrated. Linear response, observed up to 2 g l-1, was reached by including a dilution chamber in the SIA manifold. The sampling frequency was 7 analyses per hour with a relative standard deviation lower than 4%.
- Methanol concentration
- On-line monitoring
- Pichia pastoris
- Sequential injection analysis