Bioelectroanalysis with nanoelectrode ensembles and arrays
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Citations
Arrays of copper nanowire electrodes: Preparation, characterization and application as nitrate sensor
Recent Advances in Electrochemiluminescence with Quantum Dots and Arrays of Nanoelectrodes
A Sensitive Electrochemiluminescence Immunosensor for Celiac Disease Diagnosis Based on Nanoelectrode Ensembles
Microscopic imaging and tuning of electrogenerated chemiluminescence with boron-doped diamond nanoelectrode arrays
MoS 2 and WS 2 nanocone arrays: Impact of surface topography on the hydrogen evolution electrocatalytic activity and mass transport
References
Effect of thiol chemisorption on the transport properties of gold nanotubule membranes.
Mass Transport to Nanoelectrode Arrays and Limitations of the Diffusion Domain Approach: Theory and Experiment
Redox reaction mechanism of cytochrome c at modified gold electrodes
Cyclic voltammograms at coplanar and shallow recessed microdisk electrode arrays: guidelines for design and experiment.
Cyclic voltammetry at a regular microdisc electrode array
Related Papers (5)
The cyclic and linear sweep voltammetry of regular and random arrays of microdisc electrodes: Theory
Frequently Asked Questions (16)
Q2. What are the future works in "Bioelectroanalysis with nanoelectrode ensembles and arrays" ?
An alternative approach is the possibility of immobilizing the biorecognition layer on the insulating polymer which surrounds the nanoelectrodes, rather than on the nanoelectrodes themselves. Future research effort should be devoted to the development of singly addressable electrodes or of groups of nanoelectrodes. The possibility of moving from current NEEs/ NEAs ( inwhich all nanoelectrodes are interconnected ) tomore sophisticated nanoelectrode systems, in which multiple analyte determination is achieved, and the extrememiniaturization of such devices, would be particularly suitable for sensors to be used in bioanalysis, both for “ in vitro ” and “ in vivo ” analysis.
Q3. What is the main idea behind the use of a templated synthesis?
Membrane-templated synthesis is based on the idea that the pores of a host material can be used as a template to direct the growth of new materials.
Q4. How can the authors achieve growth of the metal fibres?
Growth of the metal fibres can be achieved by use of both electrochemical [21, 22] or electroless [17, 23, 24] methods of deposition.
Q5. Why is the IF proportional to the area of the ensemble exposed to the sample?
This is because, for NEEs, operating under total overlap diffusion conditions, the Faradaic current (IF) is proportional to the total geometric area of the ensemble exposed to the sample solution (Ageom, area of the nanodiscs plus insulator area) whereas the double layer capacitive current (IC), which is the maincomponent of the noise in electroanalytical chemistry, is proportional to the nanodisc area only (active area, Aact) [17].
Q6. What is the advantage of NEAs for bioanalytical applications?
The improved S/N ratio typical of NEEs makes them particularly suitable for direct determination of electroactive species at low concentrations.
Q7. Why is the NEAs used for bioanalytical applications so often recessed?
it is worth stressing that, because of the nanolithographic process itself, quite often the nanoelectrodes obtained are slightly recessed, so that theoretical model for such geometry must be taken into account [50, 55].
Q8. What are some recent examples of bioelectroanalytical applications of nanostructure?
These include use of nanoelectrode arrays and/or ensembles for direct electrochemical analysis of pharmacologically active organic compounds or redox proteins, and the development of functionalized nanoelectrode systems and their use as catalytic or affinity electrochemical biosensors.
Q9. What is the process of forming a PC-based nanoelectrode?
These PC-based nanoelectrodes are fabricated by patterning arrays of holes in a thin film of PC spin-coated on a gold layer on Si–Si3N4 substrate.
Q10. What is the simplest way to make a PC-based nanoelectrode?
These holes can be used as recessed nanoelectrodes, and by further electrochemical deposition of gold, it is possible to fill the holes partially or totally to obtain arrays of inlaid nanodisc electrodes (Fig. 6).
Q11. What is the main idea behind the use of a templated ensemble of nanoelectrod?
The first template synthesis of NEEs for electrochemical use was described by Menon and Martin [17] who deposited gold nanofibres with a diameter as small as 10 nm within the pores of track-etched polycarbonate (PC) membranes by a chemical (electroless) method and obtained a random ensemble ofmetal nanodisc electrodes surrounded by the insulating polymer.
Q12. How is the analyte deposited on the surface of the gold nanowires?
In this approach the analyte is adsorbed on the surface of the gold nanowires and analysed directly by SWV, resulting in an LOD as low as 8.9×10−8molL−1 (S/N=3) [84].
Q13. What is the way to measure the amount of biomolecules on nanowires?
Alternative designs: gold nanoparticles on NEEsUse of etched 3D NEEs to increase the amounts of biomolecules adsorbed on gold nanowire surfaces proved to be a viable process, although with the drawback of an increase of the capacitive current and, consequently, an increase of the S/N ratio [9].
Q14. What is the difference between NEEs and conventional electrodes?
Because the main advantage of NEEs over conventional macro (mm-sized) or even ultramicro (μm-sized) electrodes is a dramatic lowering of double-layer capacitive currents [17, 69], if it is not possible to directly characterize the morphology of the electrodes, the lack of this characteristic should be taken into account to discriminate well-prepared from defective NEEs.
Q15. What is the drawback of etching the polymer?
One way of reducing this drawback has recently been proposed [88]—increasing the nanoelectrode area not by etching the templating polymer but depositing gold nanoparticles on the gold nanodisc electrodes.
Q16. What is the simplest way to make a PC-based array of nanoelectrod?
As shown in Fig. 5, because the properties of PC enable its use as a high-resolution e-beam resist, it is possible to obtain a perfectly ordered array of nano-holes, of controlled diameter, as small as 50 nm [55].