Investigation of Hemoglobin/Gold Nanoparticle Heterolayer on Micro-Gap for Electrochemical Biosensor Application

Abstract

In the present study, we fabricated a hemoglobin/gold nanoparticle (Hb/GNP) heterolayer immobilized on the Au micro-gap to confirm H2O2 detection with a signal-enhancement effect. The hemoglobin which contained the heme group catalyzed the reduction of H2O2. To facilitate the electron transfer between hemoglobin and Au micro-gap electrode, a gold nanoparticle was introduced. The Au micro-gap electrode that has gap size of 5 µm was fabricated by conventional photolithographic technique to locate working and counter electrodes oppositely in a single chip for the signal sensitivity and reliability. The hemoglobin was self-assembled onto the Au surface via chemical linker 6-mercaptohexanoic acid (6-MHA). Then, the gold nanoparticles were adsorbed onto hemoglobin/6-MHA heterolayers by the layer-by-layer (LbL) method. The fabrication of the Hb/GNP heterolayer was confirmed by atomic force microscopy (AFM) and surface-enhanced Raman spectroscopy (SERS). The redox property and H2O2 detection of Hb/GNP on the micro-gap electrode was investigated by a cyclic voltammetry (CV) experiment. Taken together, the present results show that the electrochemical signal-enhancement effect of a hemoglobin/nanoparticle heterolayer was well confirmed on the micro-scale electrode for biosensor applications.

Real-time kinetic analysis and detection of glycated hemoglobin A1c using a quartz crystal microbalance-based aptasensor

“…4c), particles with a height of about 4 nm were detected, which could be inferred to be the size of the HbA1c proteins. 34 According to these AFM data, it could be again reaffirmed that the aptamer-functionalized surfaces were able to recognize the HbA1c proteins.…”

“…These observed particles could be correlated with the size of DNA aptamers, as similarly reported in previous studies. 32–34 After the HbA1c binding (Fig. 4c), particles with a height of about 4 nm were detected, which could be inferred to be the size of the HbA1c proteins.…”

Peroxidase-like activity of hemoglobin-based hybrid materials against different substrates and their enhanced application for H2O2 detection

“…The nanoflower, which has nano-sized plates, has been applied to drug transportation, gene therapy, biosensor diagnosis and therapy [9]. Protein-based biomaterials are a particularly effective tool for characterizing the target analyte [10][11][12]. To date, various researches have been carried out using such materials as carbon, metal, metal oxide-based nanoparticles, and metal complexes to design functional synthetic materials with peroxidase and catalase-like activities [13][14][15].…”

“…Among these, hemoglobin is widely used in the analysis because of its well-known molecular structure, its cheapness, commercial usable and high stability [10,18]. Hemoglobin is a 5.5 nm sized protein with tetrameric, globuler and oxygen carrier, each monomer weighing 17 kDa [11,16,19,20].…”

Reflective FT‐NIR and SERS studies of HER‐II breast cancer biomarker using plasmonic‐active nanostructured thin film immobilized oriented antibody

“…SERS active substrates can be colloidal, that is, solution-based, solid-supported substrates where various types, shapes and sizes of nanostructures including spherical nanoparticles, nanorods, nanostars, nanoshells and thin film substrate where a controlled layer of plasmonic material is vapor deposited on the substrate by different techniques such as electron beam [31,32]. In particular, thin films have been a topic of research in both nanotechnology and biochemical applications, with uses in various electrochemical and optical sensors for signal enhancement [33][34][35]. Gold metal surfaces are photostable and biocompatible because of their inert surface, nontoxic, involve relatively easy synthesis, allow for functionalization and surface conjugation chemistry, there is an absence of photobleaching and they are resistant to oxidation [36,37].…”