Dual role of hydrogen peroxide on the oxidase-like activity of nanoceria and its application for colorimetric hydrogen peroxide and glucose sensing

Abstract

Nanoceria (cerium oxide nanoparticles) exhibits excellent catalytic activity towards chromogenic substrate 3,3,5,5-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide (H 2 O 2 ), which has been reported. However, the understanding on the interaction between H 2 O 2 and nanoceria is far from complete. Herein, we further studied the interaction between H 2 O 2 and dextran-coated nanoceria and found that H 2 O 2 plays a dual role on nanoceria's oxidase activity both as an inhibitor and a promoter, depending on its concentration. In millimolar levels, H 2 O 2 can promote nanoceria's oxidase activity, however, micromolar concentration of H 2 O 2 could inhibit its catalytic activity. In addition, this inhibiting effect is linearly dependent on the concentration of H 2 O 2 . Based on these findings, a simple, rapid and highly sensitive colorimetric method was established for the determination of H 2 O 2 with a limit of detection (LOD) of 2.5 µM (3σ/slope) and a linear range from 4−40 µM. When coupled with glucose oxidase, glucose can be detected down to 2 µM in the linear range of 4−40 µM. Furthermore, this method was successfully applied for the determination of glucose in mouse serum samples. With the new understanding of the interaction between H 2 O 2 and nanoceria, applications of nanoceria-based sensors in engineering, biotechnology and environmental chemistry can be further exploited.

Hot Topics and Challenges of Regenerative Nanoceria in Application of Antioxidant Therapy

“…Nanoceria becomes an ideal and impacted biosensor, not only because it can provide immediate and real time measurement of biomolecules [32,33], but also because it can have many advantages over organic biosensor, such as photo bleachable, toxic, expensive, and easily degradable. Nanoceria has already become a hot topic in biosensor fields.…”

Ceria Nanoparticles as Enzyme Mimetics

“…The utilization of nanoceria as oxidase under some special circumstances was also reported. Recently, nanoceria have been used for several applications either in biotic conditions or abiotic conditions, such as antioxidants, [63][64][65] capping [36] and neuroprotection agents, [66][67][68][69][70][71][72] biosensors, [23,28,73] immunoassays, [31,32,74] color indicator [27,[75][76][77][78][79] and so on.…”

“…The negatively charged target DNA could not only be adsorbed on the surface of nanoceria with positive charge, but also be adsorbed on positively charged 3,3',5,5'-tetramethylbenzidine (TMB), blocking the direct contaction of nanoceria with TMB and resulting in a lower colorimetric signal. Furthermore, Guo et al [78] studied the interaction between H 2 O 2 and nanoceria for the TMB colorimetric determination was dependent on the H 2 O 2 concentration. The results showed that the oxidase mimetic activity of nanoceria would be promoted when the H 2 O 2 concentration was above millimolar level, while under this level the catalysis activity was inhibited.…”

Post Cleaning for FEOL CMP with Silica and Ceria Slurries

“…In this study, diluted hydrogen peroxide between 2% and 10% by volume is flushed into the non-contact megasonic cleaner to facilitate the removal of ceria abrasive particles. 16 In the current study, the concentration of H 2 O 2 in the megasonic tank is on the order of 1.0 M (between 10% and 2% by vol.). Consequently, the oxidation of Ce 3+ to Ce 4+ should be the main mechanism involved.…”