Dual-readout smartphone-assisted and spectrophotometric colorimetric nanosensor for enzymeless bisphenol A detection.

A proof-of-concept approach is introduced that uses silver nanoparticles modified with Epimedium plant extract (EE-AgNPs) for BPA detection. The EE-AgNPs aggregate in the presence of BPA, demonstrating a measurable color change. This color change is monitored via a smartphone, enabling the prompt on-site determination of BPA. The sensor exhibited a linear response within the range 0.1-50 µM and a limit of detection (LOD) of 22 nM, which is below the thresholds set by the United States Food and Drug Administration, the National Health and Family Planning Commission of China, and European Union's specific migration limits, rendering it appropriate for the testing of polluted water and biological samples. Moreover, the study provides promising recoveries for BPA in water and biological specimens. The assimilation of the colorimetric system with smartphone offers a potential, cost-effective, and efficient option to traditional chromatographic approaches, especially for the initial evaluation of biological and polluted water samples.