Development of a Field-Deployable Optical Biosensing Instrument and a Novel Cuvette-Based Bioluminescence Detection Method for Rapid, On-Site Effect-Based Screening of Unprocessed Environmental Sediments

Sediment-associated contaminants pose persistent environmental risks, yet conventional sediment assessment workflows often require laboratory infrastructure and extensive sample preparation, limiting their suitability for rapid field monitoring. This study presents the development of a field-deployable instrument and a novel cuvette-based detection method for rapid effect-based sediment monitoring. Proteotoxic-stress-reporting Escherichia coli TV1061 cells were immobilized in a crosslinked alginate hydrogel at the bottom of standard cuvettes, thereby enabling direct contact with an overlying sediment layer while maintaining physical separation and a clear optical detection zone. The developed instrument enabled rapid sequential cuvette measurements under field conditions. An optimal incubation time (OIT) of 85 min was established. Measurements of sediment extracts showed good agreement with a conventional microplate reader assay (Pearson’s r = 0.977). Analytical characterization using ethanol showed a concentration-dependent response, with 0.75% (v/v), the lowest tested concentration, yielding a significant response on both the instrument and a conventional microplate reader. Direct analysis of unprocessed environmental sediments produced significant inhibition of the bioluminescent responses, and on-site measurements demonstrated the feasibility of operating the complete platform under field conditions. Overall, the platform provides a practical approach for rapid, on-site effect-based screening of environmental sediments while substantially simplifying sample preparation and biosensor operation.