Application of Paper-Supported Printed Gold Electrodes for Impedimetric Immunosensor Development

Abstract

In this article, we report on the formation and mode-of-operation of an affinity biosensor, where alternate layers of biotin/streptavidin/biotinylated-CRP-antigen/anti-CRP antibody are grown on printed gold electrodes on disposable paper-substrates. We have successfully demonstrated and detected the formation of consecutive layers of supra-molecular protein assembly using an electrical (impedimetric) technique. The formation process is also supplemented and verified using conventional surface plasmon resonance (SPR) measurements and surface sensitive characterization techniques, such as X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The article provides a possible biosensor development scheme, where—(1) fabrication of paper substrate (2) synthesis of gold nanoparticle inks (3) inkjet printing of gold electrodes on paper (4) formation of the biorecognition layers on the gold electrodes and (5) electrical (impedimetric) analysis of growth—all are coupled together to form a test-structure for a recyclable and inexpensive point-of-care diagnostic platform.

Oligomerization Alters Binding Affinity between Amyloid Beta and a Modulator of Peptide Aggregation

“…To functionalize the gold sensor surface we followed the standard protocol, as described by 23 and adapted it to using biotinylated Aβ peptide as the ligand layer as shown in Fig. 2.…”

“…MP-SPR is a powerful technique for studying label-free biomolecular interaction measured in real-time, providing detailed analysis of affinity and kinetics of small molecule interactions as well as a unique method for measuring peptide and protein self-assembly 23 . Here we use MP-SPR to investigate how spin labeled fluorenes decrease Aβ self-assembly and aggregation.…”

Electrochemical detection in paper-based analytical devices using microwire electrodes

“…The most printed metallic ink is silver, and has been used primarily for reference electrodes [10,20]. Screen-printed gold ink has also been used as a working electrode material [21,22]. While inks and pastes are attractive and will continue to be used, they suffer from higher resistance due to the presence of polymer binders.…”

Nanomaterial-Based Electrochemical and Colorimetric Sensors for On-Site Detection of Small-Molecule Targets

“…To frame a conductive gold film on a kaolin-covered paper substrate with no layout, Määttänen et al inkjet-printed a layer of dodecanethiol-altered AuNPs and then used infrared sintering to transform these nonconductive particles into a conductive gold film. [62][63][64][65] These films exhibit ∼10% of the conductivity of solid bulk gold and have been used in a variety of different applications.…”

“…[62][63][64][65] Hu et al created permeable gold terminals on cellulose layers by consolidating inkjet-printed, non-conductive AuNPs with the self-catalytic development of the printed particles to frame a consistent gold leading layer on the paper. 66 Although these paper-based permeable gold film clusters showed great conductivity and enabled sensitive electrochemical detection of oxygen, their manufacture required numerous creation steps-including seven rounds of inkjet printing and eight cycles of AuNP synthesis.…”