Rapid detection and quantification of glyphosate in water using a handheld portable biosensor.

Glyphosate is the most extensively applied systemic herbicide worldwide, yet its safety remains under scrutiny, with ongoing investigations into potential carcinogenicity. Epidemiological studies associate chronic glyphosate exposure with elevated risks of non-Hodgkin lymphoma and possible endocrine disruption, emphasizing the need for sensitive detection methods. Here, we report a handheld enzymatic biosensor, GlyphoSense Chip, for direct, rapid detection of underivatized glyphosate in drinking water. The device integrates a photodiode-based CMOS chip with an engineered glyphosate N-acetyltransferase and a colorimetric reaction, achieving a sensitivity of 38 µV·mL µg·s and quantification within one minute. Biosensor response was linear over 0.016-12.5 µg mL (R = 0.993) with a detection limit of 0.028 µg mL. Recovery analysis in fortified tap water yielded relative standard errors of 1.2-5.8%, and results were statistically indistinguishable from quantitative mass spectrometry (p > 0.05). This work establishes a robust, field-deployable platform for glyphosate monitoring in water resource safety applications.