Importance of the surface chemistry of nanoparticles on peroxidase-like activity

• Published in: Biochemical and biophysical research communications Vol. 491; no. 1; pp. 15 - 18
• Main Authors: El-Sayed, Ramy, Ye, Fei, Asem, Heba, Ashour, Radwa, Zheng, Wenyi, Muhammed, Mamoun, Hassan, Moustapha
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 09-09-2017
• Subjects: Benzidines - chemistry; Enzyme Activation; Enzyme mimic; Gold - chemistry; Gold nanorods; Hollow gold nanospheres; Hydrogen Peroxide - chemistry; Materials Testing; Medicin och hälsovetenskap; Metal Nanoparticles - chemistry; Metal Nanoparticles - ultrastructure; Oxidation-Reduction; Particle Size; Peroxidase - chemistry; Peroxidase - ultrastructure; Peroxidase activity; Substrate Specificity; Surface chemistry; Surface Properties; Enzyme mimic; Hollow gold nanospheres; Gold nanorods; Peroxidase activity; Surface chemistry
• ISSN: 0006-291X; 1090-2104; 1090-2104
• DOI: 10.1016/j.bbrc.2017.07.014

We report the studies on origin of peroxidase-like activity for gold nanoparticles, as well as the impact from morphology and surface charge of nanoparticles. For this purpose, we have synthesized hollow gold nanospheres (HAuNS) and gold nanorods (AuNR) with different morphology and surface chemistry to investigate their influence on the catalytic activity. We found that citrate-capped HAuNS show catalyzing efficiency in oxidation reaction of 3,3′,5,5′-tetramethylbenzidine (TMB) by hydrogen peroxide (H2O2) and it is superior to that of cetyltrimethylammonium bromide (CTAB)-capped AuNR. The kinetics of catalytic activities from HAuNS and AuNR were respectively studied under varied temperatures. The results indicated that surface chemistry rather than morphology of nanoparticles plays an important role in the catalytic reaction of substrate. Furthermore, influencing factors such as pH, amount of nanoparticle and H2O2 concentration were also investigated on HAuNS-catalyzed system. The great impact of nanoparticle surface properties on catalytic reactions makes a paradigm in constructing nanozymes as peroxidase mimic for sensing application.
•Hollow gold nanoparticles have peroxidase-like activity.•Surface chemistry, not morphology, plays a vital role in peroxidase efficiency.•Peroxidase activity is influenced by pH, particle and H2O2 concentrations.