Sequential injection analysis system for electronic tongues modelling and calibration process

Electronic tongues (ET) are low cost instruments to real time liquid samples determination. There is a vast field of application for ET (i.e. chemical, pharmaceutical, food and environmental analysis). Main disadvantage of ET is the large amount of data implied in the modeling and calibration process. To overcome this disadvantage an automated Sequential Injection Analysis (SIA) system is implemented in this work. By aspirating and mixing sequentially reactive and solutions a lot of samples can be obtained in a fully automated way. Totally controlled by a virtual instrument (VI) developed in LabVIEW 2009, the SIA system was operated at flow rates from 8.89 ml/min to 10.12 ml/min with a maximum standard deviation of 4.03% (lower was 1.5%). After flow rate characterization process an automated dilution process was successfully tested with an ion selective electrode of Sodium. Concentration range from 0.0365μM to 0.04 M was tested. Both steady state and transient response were acquired by the system and log period operation was also obtained. Coupling the system with a sensor array and an appropriate math tool is the next step in order to obtain an ET.