Argentine researchers develop mobile phone-based phosphate detection system

Researchers from the National Scientific and Technical Research Council (CONICET) and the University of Buenos Aires (UBA) have developed an innovative system that uses mobile phones to rapidly and efficiently measure phosphate (PO₄³⁻), an essential chemical compound involved in numerous biological and environmental processes. The new technology is expected to broaden access to phosphate analysis in scientific, agricultural, and healthcare settings, reports BRICSLat, a partner of TV BRICS.

Phosphate quantification plays an important role in the diagnosis of rare diseases. In agriculture, phosphate levels are equally significant, as approximately 60 per cent of cultivated land in Argentina remains below the critical phosphate threshold required for optimal crop development.

Luis Gonzalez Flecha, lead researcher of the project and specialist at the Institute of Chemistry and Biological Physical Chemistry "Prof. Alejandro C. Paladini" (IQUIFIB), explained that current phosphate detection techniques frequently rely on costly equipment and highly specialised personnel. According to him, the newly developed method overcomes these limitations through a combination of a novel reagent and mobile phone-based analysis, while also demonstrating high sensitivity, accuracy, reproducibility, and reliability during testing.

Researchers believe that, following patent registration and technology transfer procedures, the method could be adopted by research laboratories, educational institutions, and chemical analysis centres. The technology also has potential applications in agricultural monitoring and environmental quality assessment.

The system operates through a straightforward process. Once the reagent is added to a sample, a colour reaction develops within approximately 30 minutes due to the presence of malachite green dye. The resulting colour intensity remains stable for several hours and is directly proportional to the concentration of phosphate in the sample. Mobile phone camera sensors capture the light absorbed by the solution and convert it into digital signals, enabling precise measurement through specialised open-source software.

Alvaro Recoulat Angelini, first author of the study and researcher at the Molecular Biophysics Laboratory of IQUIFIB, highlighted that the possibility of carrying out measurements directly in the field with a mobile phone could support more decentralised and frequent monitoring schemes. He added that this approach could facilitate broader participation from environmental agencies, municipalities, sanitation services, and citizen science initiatives.

The researchers also improved the stability of the reagent by incorporating a copolymer widely used in pharmaceutical formulations and cell cultures. This optimisation allows the reagent to remain stable for more than a year at room temperature without significant loss of sensitivity. The team reported that the new formulation achieves sensitivity levels around 30 times higher than those of conventional phosphate detection methods.

Beyond healthcare and agriculture, the methodology could contribute to water quality assessment and biochemical research involving phosphate-releasing enzymes linked to cellular energy transformation. The Argentine scientists emphasised that advances in mobile phone camera technology and the relatively low cost of such devices are expected to drive further transformation in optical analytical instrumentation in the coming years.