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General Preparation of Heme Protein Functional Fe 3 O 4 @Au‐Nps Magnetic Nanocomposite for Sensitive Detection of Hydrogen Peroxide
Author(s) -
Xu Xuan,
Song Lishu,
Zheng Qiqin,
Cao Xiaodong,
Yao Cheng
Publication year - 2017
Publication title -
electroanalysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.574
H-Index - 128
eISSN - 1521-4109
pISSN - 1040-0397
DOI - 10.1002/elan.201600457
Subject(s) - hydrogen peroxide , ascorbic acid , biosensor , electron transfer , nanocomposite , nanoparticle , nuclear chemistry , chemistry , detection limit , biomolecule , magnetic nanoparticles , materials science , inorganic chemistry , analytical chemistry (journal) , photochemistry , nanotechnology , organic chemistry , chromatography , food science
Stable magnetic nanocomposite of gold nanoparticles (Au‐NPs) decorating Fe 3 O 4 core was successfully synthesized by the linker of Boc‐L‐cysteine. Transmission electron microscope (TEM), energy dispersive X‐ray spectroscopy (EDX) and cyclic voltammograms (CV) were performed to characterize the as‐prepared Fe 3 O 4 @Au‐Nps. The results indicated that Au‐Nps dispersed homogeneously around Fe 3 O 4 with the ratio of Au to Fe 3 O 4 nanoparticles as 5–10/1 and the apparent electrochemical area as 0.121 cm 2 . After self‐assembly of hemoglobin (Hb) on Fe 3 O 4 @Au‐Nps by electrostatic interaction, a hydrogen peroxide biosensor was developed. The Fe 3 O 4 @Au‐Nps/Hb modified GCE exhibited fast direct electron transfer between heme center and electrode surface with the heterogeneous electron transfer rate constant ( Ks ) of 3.35 s −1 . Importantly, it showed excellent electrocatalytic activity towards hydrogen peroxide reduction with low detection limit of 0.133 μM ( S / D =3) and high sensitivity of 0.163 μA μM −1 , respectively. At the concentration evaluated, the interfering species of glucose, dopamine, uric acid and ascorbic acid did not affect the determination of hydrogen peroxide. These results demonstrated that the introduction of Au‐Nps on Fe 3 O 4 not only stabilized the immobilized enzyme but also provided large surface area, fast electron transfer and excellent biocompatibility. This facile nanoassembly protocol can be extended to immobilize various enzymes, proteins and biomolecules to develop robust biosensors.