Amino Coated Gold Nanorods Based Amperometric Glucose Detection (original) (raw)
Related papers
Detection of glucose using gel-templated gold nanostructured electrodes
A precise monitoring of glucose level in blood is of high importance in clinical medicine, thus, sensitive, rapid and reliable methods for its detection are required. In this work, gelatin templated gold nanostructures were fabricated in order to improve the sensitivity of glucose analysis. SEM and AFM were used for characterization of the created surfaces. Glucose was detected by a direct electrochemical oxidation during cyclic voltammetry in alkaline solution. Limit of detection of 10 μM was achieved in aqueous samples. The sensor was also able to detect real concentration of glucose in deproteinised human serum with negligible effect of interferents. All results were verified by commercial glucometer and the standard kit for photometric detection of glucose.
Sensors and Actuators B: Chemical, 2011
This work reports the fabrication and application of a glucose biosensor based on the catalytic effect of gold nanoparticles (AuNPs) on enzymatic reaction for blood glucose determination. AuNPs were initially in situ synthesized on the surface of an eggshell membrane (ESM) which was subsequently immobilized with glucose oxidase (GO x ) to produce a GO x -AuNPs/ESM. The GO x -AuNPs/ESM was positioned on the surface of an oxygen electrode to form a GO x -AuNPs/ESM glucose biosensor. The effects of pH, concentration of phosphate buffer solution and amount of GO x on the response of the GO x -AuNPs/ESM glucose biosensor were studied in detail. AuNPs on GO x /ESM can improve the calibration sensitivity (30% higher than GO x /ESM without AuNPs), stability (87.3% of its initial response to glucose after 10-week storage) and shortens the response time (<30 s) of the glucose biosensor. The linear working range for the GO x -AuNPs/ESM glucose biosensor is 8.33 M to 0.966 mM glucose with a detection limit of 3.50 M (S/N = 3). The biosensor has been successfully applied to determine the glucose in human blood serum samples and the results compared well to a standard spectrophotometric method commonly used in hospitals. Our work demonstrates that the developed GO x -AuNPs/ESM glucose biosensor has potential in biomedical analysis.
Gold Nanoparticles and Polypyrrole for Glucose Biosensor Design
Procedia Engineering, 2012
In this study electrochemistry of glucose oxidase (GOx) immobilized on a carbon rod electrode modified by gold nanoparticles (Au-NPs) and-conjugated polymer-polypyrrole (Ppy) was studied. Au-NPs facilitated indirect electron transfer via red-ox mediator and showed a positive effect on the amperometric signals of such type electrodes. Several types of electrodes modified by GOx and Au-NPs of different sizes and additionally covered by Ppy layer were investigated. The sensitivity and stability of developed biosensors were evaluated and compared.
Enzyme Immobilization on Gold Nanoparticles for Electrochemical Glucose Biosensors
Nanomaterials
More than 50 years have passed since Clark and Lyon developed the concept of glucose biosensors. Extensive research about biosensors has been carried out up to this day, and an exponential trend in this topic can be observed. The scope of this review is to present various enzyme immobilization methods on gold nanoparticles used for glucose sensing over the past five years. This work covers covalent bonding, adsorption, cross-linking, entrapment, and self-assembled monolayer methods. The experimental approach of each modification as well as further results are described. Designated values of sensitivity, the limit of detection, and linear range are used for the comparison of immobilization techniques.
Biosensors
In recent years, many efforts have been made to develop rapid, sensitive and user-friendly glucose biosensors for monitoring blood glucose concentration in patients. In this study, the electrochemical glucose biosensors based on graphite rod (GR) electrode electrochemically modified with dendritic gold nanostructures (DGNs) and glucose oxidase (GOx) were developed. Phenazine methosulfate was used as a soluble redox mediator. Three GOx immobilization methods: adsorption on DGNs and cross-linking with glutaraldehyde (GA) vapour (GA-GOx/DGNs/GR), covalent immobilization on DGNs modified with 11-mercaptoundecanoic acid self-assembled monolayer (SAM) (GOx-SAM/DGNs/GR) and covalent immobilization on SAM with additional cross-linking with GA vapour (GA-GOx-SAM/DGNs/GR), were used. It was determined that GA significantly improved the stability of the enzyme layer. The difference of maximal current generated during the enzymatic reaction (ΔImax) equal to 272.06 ± 8.69 µA was obtained using a...
The electrochemistry of glucose oxidase (GOx) immobilized on a graphite rod electrode modified by gold nanoparticles (Au-NPs) was studied. Two types of amperometric glucose sensors based on GOx immobilized and Au-NPs modified working electrode (Au-NPs/GOx/graphite and GOx/Au-NPs/graphite) were designed and tested in the presence and the absence of N-methylphenazonium methyl sulphate in different buffers. Results were compared to those obtained with similar electrodes not containing Au-NPs (GOx/graphite). This study shows that the application of Au-NPs increases the rate of mediated electron transfer. Major analytical characteristics of the amperometric biosensor based on GOx and 13 nm diameter Au-NPs were determined. The analytical signal was linearly related to glucose concentration in the range from 0.1 to 10 mmol L −1 . The detection limit for glucose was found within 0.1 mmol L −1 and 0.08 mmol L −1 and the relative standard deviation in the range of 0.1-100 mol L −1 was 0.04-0.39%. The τ 1/2 of V max characterizes the storage stability of sensors: this parameter for the developed GOx/ graphite electrode was 49.3 days and for GOx/Au-NPs/ graphite electrode was 19.5 days. The sensor might be suitable for determination of glucose in beverages and/or in food.
The Journal of Physical …, 2009
A new amperometric biosensor, based on deposition of glucose oxidase (GOD) onto crystalline gold (Au) nanoparticle modified multiwalled carbon nanotube (MWNT) electrode, is presented. MWNTs have been synthesized by catalytic chemical vapor decomposition of acetylene over rare-earth-based AB 2 (DyNi 2 ) alloy hydride catalyst. Purified MWNTs have been decorated with nanocrystalline Au metal clusters using a simple chemical reduction method. The characterization of metal-decorated CNTs has been done using X-ray diffraction analysis, scanning electron microscopy, transmission electron microscopy (TEM), high-resolution TEM, and energy-dispersive X-ray analysis. Amperometric biosensor fabricated by depositing GOD over Nafionsolubilized Au-MWNT electrode retains its biocatalytic activity and offers fast and sensitive glucose quantification. The performance of the biosensor has been studied using cyclic voltammetry, amperometry, and hydrodynamic voltammetry, and the results have been discussed. The fabricated glucose biosensor exhibits a linear response up to 22 mM glucose and a detection limit of 20 µM.
Biosensors
In this study, graphite rod (GR) electrodes were electrochemically modified by dendritic gold nanostructures (DGNs) followed by immobilization of glucose oxidase (GOx) in the presence of mediator phenazine methosulfate (PMS). Modified with polyaniline (PANI) or polypyrrole (Ppy), GOx/DGNs/GR electrodes were used in glucose biosensor design. Different electrochemical methods were applied for the registration of glucose concentration, and constant potential amperometry (CPA) was chosen as the best one. PANI and Ppy layers synthesized enzymatically on the GOx/DGNs/GR electrodes extended the linear glucose determination range, the width of which depended on the duration of PANI- and Ppy-layers formation. Enzymatically formed polypyrrole was determined as the most suitable polymer for the modification and formation of the glucose biosensor instead of polyaniline, because it was 1.35 times more sensitive and had a 2.57 times lower limit of detection (LOD). The developed glucose biosensor ...
Electrochimica Acta, 2015
The amperometric glucose biosensors based on adsorbed electron transfer mediator (ETM) tetrathiafulvalene (TTF) or 1,10-phenanthroline-5,6-dione (PD) and glucose oxidase (GOx) from Aspergillus niger (GOx A.niger ), Penicillium adametzii (GOx P.adametzii ) or Penicillium funiculosum (GOx P. funiculosum ) cross-linked with glutaraldehyde were investigated. ETM and enzyme were immobilized layer by layer on bare graphite rod electrode (GR) premodified with gold nanoparticles (AuNP) of (i) 3.5 nm (GOx/ETM/AuNP 3.5 /GR), (ii) 6.0 nm (GOx/ETM/AuNP 6.0 /GR) and (iii) 13.0 nm (GOx/ETM/AuNP 13.0 /GR) size. The amperometric signals for all the developed biosensors were higher using PD in comparison with TTF. The biosensor based on GOx P.funiculosum showed higher analytical signal to glucose in a comparison to biosensors based on GOx A.niger and GOx P.adametzii . The registered current to glucose using GOx P.funiculosum / PD/AuNP 3.5 /GR electrode was linear in the glucose range from 0.1 to 10.0 mmol L À1 and the limit of detection was 0.024 mmol L À1 . Enzymatical synthesis of polypyrrole (Ppy) layer on the electrode was applied in order to expand the linear glucose detection range. After 22 h of polymerization the amperometric signal was linear in the glucose concentration range from 0.1 to 25.0 mmol L À1 , while after 69 h this rage was increased up to 50.0 mmol L À1 . Additionally Ppy layer on the electrode surface reduced the influence of interfering species on the amperometric signal. The performance of developed biosensor was investigated in human serum samples.