Recent advances in graphene-based biosensors

Due to the significance of hydrogen peroxide (H(2)O(2)) in biological systems and its practical applications, the development of efficient electrochemical H(2)O(2) sensors holds a special attraction for researchers Various materials such as Prussian blue (PB), heme proteins, carbon nanotubes (CNTs) and transition metals have been applied to the construction of H(2)O(2) sensors In this article, the electrocatalytic H(2)O(2) determinations are mainly focused on because they can provide a superior sensing performance over non-electrocatalytic ones The synergetic effect between nanotechnology and electrochemical H(2)O(2) determination is also highlighted in various aspects In addition, some recent progress for in vivo H(2)O(2) measurements is also presented Finally, the future prospects for more efficient H(2)O(2) sensing are discussed

Recent advances in electrochemical sensing for hydrogen peroxide: a review

Carbon nanotubes (CNTs) are allotropes of carbon with a nanostructure that can have a length-to-diameter ratio greater than 1,000,000. Techniques have been developed to produce nanotubes in sizeable quantities, including arc discharge, laser ablation, and chemical vapor deposition. Developments in the past few years have illustrated the potentially revolutionizing impact of nanomaterials, especially in biomedical imaging, drug delivery, biosensing, and the design of functional nanocomposites. Methods to effectively interface proteins with nanomaterials for realizing these applications continue to evolve. The high surface-to-volume ratio offered by nanoparticles resulted in the concentration of the immobilized entity being considerably higher than that afforded by other materials. There has also been an increasing interest in understanding the influence of nanomaterials on the structure and function of proteins. Various immobilization methods have been developed, and in particular, specific attachment of enzymes on carbon nanotubes has been an important focus of attention. With the growing attention paid to cascade enzymatic reaction, it is possible that multienzyme coimmobilization would be one of the next goals in the future. In this paper, we focus on advances in methodology for enzyme immobilization on carbon nanotubes.

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Carbon Nanotubes: A Review on Structure and Their Interaction with Proteins

Phenazines constitute a large group of nitrogen-containing heterocyclic compounds produced by a diverse range of bacteria. Both natural and synthetic phenazine derivatives are studied due their impacts on bacterial interactions and biotechnological processes. Phenazines serve as electron shuttles to alternate terminal acceptors, modify cellular redox states, act as cell signals that regulate patterns of gene expression, contribute to biofilm formation and architecture, and enhance bacterial survival. Phenazines have diverse effects on eukaryotic hosts and host tissues, including the modification of multiple host cellular responses. In plants, phenazines also may influence growth and elicit induced systemic resistance. Here, we discuss emerging evidence that phenazines play multiple roles for the producing organism and contribute to their behavior and ecological fitness.

/pdf/metabolism-and-function-of-phenazines-in-bacteria-impacts-on-1jyii6un2a.pdf

Metabolism and function of phenazines in bacteria: impacts on the behavior of bacteria in the environment and biotechnological processes

Nonenzymatic glucose sensor based on renewable electrospun Ni nanoparticle-loaded carbon nanofiber paste electrode.

A thionine functionalized multiwalled carbon nanotube modified electrode for the determination of hydrogen peroxide

A novel nanobiocomposite based glucose biosensor using neutral red functionalized carbon nanotubes.

Fabrication of bienzyme nanobiocomposite electrode using functionalized carbon nanotubes for biosensing applications.

Functionalized carbon nanotube-bienzyme biocomposite for amperometric sensing

The nanoscale dimensions, graphitic surface chemistry and electronic properties of multiwalled carbon nanotubes (MWNTs) make them an ideal candidate for chemical and biochemical sensing. In this paper we explore a covalent chemical strategy for functionalization of MWNTs with neutral red through carbodiimide coupling between the primary amine of neutral red and carboxyl groups of the carbon nanotubes. The construction of an amperometric sensor was achieved by abrasive immobilization of the functionalized MWNTs on a paraffin impregnated graphite electrode followed by a coating of a thin film of nafion. The neutral red functionalized MWNTs were characterized by spectroscopic and electroanalytical methods. From the voltammetric studies, MWNTs were found to exhibit a higher accessible surface area in electrochemical reactions. The modified electrode exhibited stable electrocatalytic activity toward hydrogen peroxide reduction in a wide potential range. A significant decrease in overvoltage for the reduction of hydrogen peroxide, as well as a dramatic increase in the peak currents in comparison with a bare graphite electrode were observed. Such an ability of neutral red functionalized carbon nanotubes to promote the hydrogen peroxide electron transfer reaction with a short response time (<4 s) and long-term stability, a low detection limit, an extended linear concentration range and a high sensitivity suggest great promise for dehydrogenase and oxidase based amperometric biosensors.

http://iopscience.iop.org/article/10.1088/0957-4484/18/12/125501/pdf

D. R. Shobha Jeykumari

Papers

A thionine functionalized multiwalled carbon nanotube modified electrode for the determination of hydrogen peroxide

A novel nanobiocomposite based glucose biosensor using neutral red functionalized carbon nanotubes.

Fabrication of bienzyme nanobiocomposite electrode using functionalized carbon nanotubes for biosensing applications.

Functionalized carbon nanotube-bienzyme biocomposite for amperometric sensing

Covalent modification of multiwalled carbon nanotubes with neutral red for the fabrication of an amperometric hydrogen peroxide sensor