Cost-Efective Lab-on-a-Chip Device for Seawater pH Quantification by Optical Methods

This paper presents a novel lab-on-a-chip (LOC) device for seawater pH quantification based on spectrophotometric methods. The device integrates optical, electronics and microfluidic systems, providing an autonomous, compact and portable platform for in-situ, long-term and low-cost seawater pH measurements. The developed system was validated in laboratory with measurement of various seawater samples, of different pH, within the seawater pH interval (7.50-8.30). The response of the LOC shows a high reproducibility and stability with a resolution of 0.01 pH units. Thus, the device has a high potential to be use in moored oceanic applications.