Open AccessDispersed Gold Nanoparticle Array Produced by Apoferritins Utilizing Biomineralization and Chemical Conversion
Author(s) -
Kazuyuki Nobusawa,
Naoya Okamoto,
Karen Siew Ling Chong,
Xi Lin,
Keisuke Iwahori,
Ichiro Yamashita
Publication year - 2017
Publication title -
acs omega
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.779
H-Index - 40
ISSN - 2470-1343
DOI - 10.1021/acsomega.6b00550
Subject(s) - colloidal gold , x ray photoelectron spectroscopy , substrate (aquarium) , biomineralization , materials science , layer (electronics) , nanoparticle , cationic polymerization , chemical engineering , nanotechnology , sulfide , chemistry , polymer chemistry , metallurgy , oceanography , geology , engineering
A new method for producing a dispersed gold nanoparticle (Au NP) array to anchor probe DNAs onto a DNA-sensing electrode has been developed. A homogenous gold sulfide (Au 2 S) core (precursor of Au NP) was biomineralized in the cavity of a mutant apoferritin (K98E) with enhanced negative outer-surface charges. We employed a slow chemical reaction system utilizing a stable cationic gold complex. K98E could attract the gold complex, and Au 2 S NPs were synthesized. K98E enabled dispersed placement of the synthesized Au 2 S core onto a cationic 3-aminopropyltriethoxysilane (APTES) layer on a substrate. UV-ozone treatment eliminated the protein shells and APTES layer. X-ray photoelectron spectroscopy confirmed that the Au 2 S core was reduced to Au NPs under the same treatment. Atomic force microscopy (AFM) clearly showed that the combination of apoferritin versatility, chemical system design, and UV-ozone treatment successfully produced a dispersed Au NP array on the substrate.