Size-controlled preparation of peroxidase-like graphene-gold nanoparticle hybrids for the visible detection of norovirus-like particles.
A hybrid structure of graphene-gold nanoparticles (Grp-Au NPs) was designed as a new nanoprobe for colorimetric immunoassays. This hybrid structure was prepared using chloroauric acid, sodium formate and Grp flakes at room temperature. Au NPs attached strongly onto the Grp surface, and their size was controlled by varying the sodium formate concentration. The Raman intensity of the Grp-Au NP hybrids was significantly enhanced at 1567cm-1and 2730cm-1compared with those of pristine Grp because of the electronic interaction between Au NPs and Grp. The Grp-Au NPs with a hybrid structure catalyzed the oxidation of the peroxidase substrate 3,3,5,5-tetramethylbenzidine (TMB) with H2O2, developing a blue color in aqueous solution. This catalytic activity was utilized to detect norovirus-like particles (NoV-LPs) in human serum. The enhanced colorimetric response was monitored using Ab-conjugated-Grp-Au NPs and found to depend on the NoV-LP concentration, exhibiting a linear response from 100pg/mL to 10μg/mL. The limit of detection (LOD) of this proposed method was 92.7pg/mL, 112 times lower than that of a conventional enzyme-linked immunosorbent assay (ELISA). The sensitivity of this test was also 41 times greater than that of a commercial diagnostic kit. The selectivity of the Grp-Au NPs was tested with other viruses, and no color changes were observed. Therefore, the proposed system will facilitate the utilization of the intrinsic peroxidase-like activity of Grp-Au NPs in medical diagnostics. We believe that the engineered catalytic Grp-Au NP hybrids could find potential applications in the future development of biocatalysts and bioassays.
Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan. Electronic address: rahin_sust@yahoo.com.
Syed Rahin
SR
Ahmed
Graduate School of Integrated Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan. Electronic address: kenpi901@yahoo.co.jp.
Kenshin
K
Takemeura
Department of Virology II, National Institute of Infectious Diseases, Gakuen 4-7-1, Musashi-Murayama, Tokyo 208-0011, Japan. Electronic address: litc@nih.go.jp.
Tian-Cheng
TC
Li
School of Human Science and Environment, University of Hyogo, 1-1-12 Shinzaike-Honcho, Himeji, Hyogo 670-0092, Japan. Electronic address: kitamoto@shse.u-hyogo.ac.jp.
Noritoshi
N
Kitamoto
Hidaka General Hospital, Gobo, Wakayama 644-0002, Japan. Electronic address: moqui-tom@maia.eonet.ne.jp.
Tomoyuki
T
Tanaka
Department of Infectious Diseases, Hamamatsu University School of Medicine, 1-20-1 Higashi-ku, Handa-yama, Hamamatsu 431-3192, Japan. Electronic address: tesuzuki@hama-med.ac.jp.
Tetsuro
T
Suzuki
Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan; Graduate School of Integrated Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan. Electronic address: park.enoch@shizuoka.ac.jp.
Enoch Y
EY
Park
D015374:Biosensing Techniques / Q000379:methods; D017250:Caliciviridae Infections / Q000097:blood / Q000175:diagnosis* / Q000821:virology; D003124:Colorimetry / Q000379:methods*; D006046:Gold / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D057230:Limit of Detection; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D029322:Norovirus / Q000302:isolation & purification*; D009195:Peroxidase / Q000737:chemistry
D006046:Gold; D006108:Graphite; D009195:Peroxidase
Gold nanoparticles; Graphene; Nanohybrid structure; Norovirus detection; Peroxidase-like activity