Most of the conventionally used techniques for on-line monitoring of chemical parameters require frequent calibration and maintenance. Not only does this increase the costs of ownership, but it may also provide incomplete measurements of chemical parameters and thus puts human health and environment under risk. Alternatively, single-use sensors such as those employed for glucose measurements, are only used once and display no calibration and minimal maintenance requirements. Yet, these sensors have not been widely accepted for quasi-continuous monitoring, because they still suffer from the high labour costs involved. Urged by this, a new generic multi-test analytical instrument has been designed on the basis of single-use chemical sensor technology. More specifically, the project designed a function model of a sample flow cell with a small volume to which the instrument was attached. This novelty showed increased capabilities of control of both digital outputs and inputs and measurement analysis of the analytes including data processing for calculations. The systems under investigation included ammonia, pH, dissolved oxygen, colour developing agent (CD4), LAS (linear alkyl benzene sulphonate) and iron. With the aid of microelectrode arrays, a simple membrane-less, stand-alone sensor was also developed for dissolved oxygen measurements. After a week long testing period in a sewage water treatment plant, this was found to be stable and reliable when performing continuous measurement of dissolved oxygen in activated sludge. The innovative system may provide real life analytical solutions in the fields of water quality/ pollutants monitoring and the control analysis of chemical processes. Furthermore, it has the potential to find useful applications in a broader range of analytical activities related with biomedical diagnostics and environmental pollution.