L-tyrosine-stabilized silver nanoparticles for colorimetric detection of hydrogen peroxide

Hydrogen peroxide (H₂O₂) is a type of reactive oxygen species widespread in biological tissues. It is an important biomarker of oxidative stress, cancers, asthma, etc. In this regard, development of precise and cost-effective sensors for detection of H₂O₂ in vitro and in vivo is of great significance for biomedicine. In this paper, a colorimetric method is introduced for sensing hydrogen peroxide using tyrosine-stabilized silver nanoparticles. In aqueous solutions, the colorimetric method demonstrated a linear range of 0.4-5 μM with a detection limit (LOD) of 150 nM, whereas in human blood serum the linear range was within 0.7-20 μM characterized by a LOD of 250 nM. Recovery tests in blood serum yielded results within the acceptable range 96-101%, confirming the method's accuracy and reliability. Possible mechanisms of silver nanoparticles/nanoclusters interaction with H₂O₂ during its detection were examined using fluorescence spectroscopy and dynamic light scattering methods.