Pd nanoparticles stabilized by bitter gourd polysaccharide with peroxidase properties for H2O2 detection

The development of nanozymes using noble metal nanoparticles to replace natural peroxidase in bio-related detection has been gain great interest. Noble metal nanoparticles with small size have large specific surface area. However, small noble metal nanoparticles tend to aggregate without stabilizer. In this paper, small Pd nanoparticles (3-6 nm) stabilized by bitter gourd polysaccharide (Pdn-BGP NPs) were prepared by using bitter gourd polysaccharide as reducing agent and stabilizing agent. Pd25-BGP NPs had peroxidase-like catalytic property. And the catalytic kinetics of Pd25-BGP NPs towards substrates conformed to the Michaelis-Menten equation. Furthermore, a method was established to detect H2O2 using Pd25-BGP NPs. The linear range and detection limit of this method was 20-320 μM and 2.04 μM, respectively. Finally, Pd25-BGP NPs had good biocompatibility when the concentration was less than 80 μg/mL. The prepared Pd nanoparticles with high stability showed their good prospect in H2O2 detection.