Biomedical Engineering Reference
In-Depth Information
11
Application of Bioconjugated Nanoporous
Gold Films in Electrochemical Biosensors
Leila Kashei -Kheyrabadi
1
, Abolhassan Noori
2
and Masoud Ayatollahi
Mehrgardi*
,1
1
Department of Chemistry, University of Isfahan, Isfahan, Iran
2
Department of Chemistry, Tarbiat Modares University, Tehran, Iran
Abstract
h e conjugation of biomolecules and nanostructured materials in the last decade
has opened a promising horizon to many aspects of modern science. Considerable
attention has been paid to the development of new nanomaterials with suitable
hydrophilicity, high porosity, and large surface area for various biomolecule
immobilizations. Nanostructured materials, in particular a nanoporous structure,
could provide large surface area for high loading capacities for the biomolecules.
A wide variety of biomolecules including proteins and nucleic acids have been
employed in this i eld. Deoxyribonucleic acids (DNAs), Ribonucleic acids (RNAs),
aptamers and aptazymes, whose functions are beyond the conventional genetic
roles of nucleic acids, are collectively located in the nucleic acids (NAs) category.
Also, various proteins including antibodies, enzymes, redox proteins, etc., have
been applied as the recognition layer in nanoporous-based biosensors. Many
approaches have been adopted for the surface functionalization of porous mem-
branes, in which chemisorption of thiol compounds onto the surfaces of nano-
porous gold (NPG) i lms takes place with high ai nity. h e NPG i lm modii ed
electrodes have been used for the construction of novel label-free electrochemi-
cal immunosensors for ultrasensitive detection of cancer biomarker using specii c
antibodies. Nanoporous materials have made it possible to precisely immobilize
enzymes and proteins while retaining or enhancing their activities and lifetimes,
which is critical for enhancing biosensor performance. h ere is also an intriguing
possibility to functionalize nanoporous materials with smart polymers in order
to modulate biomolecular transport in response to either external (e.g., light and
magnetic i eld) or internal stimuli (e.g., redox, enzymes and pH). h ese ef orts
