Multicolor biosensor for hyaluronidase based on target-responsive hydrogel and etching of gold nanorods by H₂O₂

Hyaluronidase (HAase) is a potential tumor biomarker for diseases of the digestive tract and nervous system, the development of simple and sensitive techniques for HAase determination is urgent needed. Gold nanorods (Au NRs) can be etched by H₂O₂ with high efficiency and display color changing. In this work, a HAase-responsive hydrogel system had been designed and the amount of H₂O₂ spilled from the system had a close relationship with the amount of HAase, then the spilled H₂O₂ had been applied to etch Au NRs. The color change of the solution was used to realize semi-quantitative determination of HAase. Furthermore, the longitudinal peak shift of Au NRs had a linear correlation with the concentration of HAase in the range of 10-60 U/mL (within 40 min) and the limit of detection (LOD) was 3.8 U/mL (S/N = 3), which can be used to realize accurate quantitative analysis of HAase. The proposed method has been applied to monitor HAase in serum of pancreatic cancer patients with satisfied results.