Next generation fluorescence sensor with multiple excitation and emission wavelengths - NeXOS MatrixFlu-UV

Ocean health observations have been performed for hundreds of years. Optimizing the process of gathering information on status as well as changes of oceanographic parameters through research cruises is however still challenging and recently developed robotic opportunities need to be enhanced. Using mobile and autonomous platforms like gliders, buoys and surface platforms (here sailbuoys) is an innovative and cost-effective way to obtain large datasets even under unfavorable conditions. Developing suitable sensors, like the optical fluorescence sensor MatrixFlu-UV, which can be deployed on those platforms, is one of the major goals of "Next generation Low-Cost Multifunctional Web Enabled Ocean Sensor Systems Empowering Marine, Maritime and Fisheries Management" (NeXOS, a European Union funded project). The sensor concept of multiple excitation and emission configuration, its proof-of-principle and verification results for colored dissolved organic matter related chemical compound humic acid are represented. An extended concentration series, using sensor and reference detector in parallel, showed clearly a linear correlation (coefficient of determination of R-2 = 0.99) between data measured with the sensor and the reference measurement. In combination with the other wavelengths excitation-emission combinations, the MatrixFlu-UV offers a true ultra-compact multi-parameter option for upcoming ocean observation activities.