Enzyme electrodes are biochemical transducers. They function by converting biochemical reactions into electrochemical processes. This functionality could potentially give rise to a new generation of implantable medical devices such as biofuel cells and biosensors. The main aim of this study was to fabricate and characterise enzyme electrodes for potential use in these applications. The approach involved testing various materials such as different types of enzyme, polymeric electron transfer mediators, enzyme entrapment materials, conductive supports and matrices and biocompatible polymers. Various enzyme immobilisation methods were used and various polymeric electron transfer mediators were fabricated and tested. The investigation was based primarily on electrochemical techniques. The materials and immobilisation techniques presented could potentially be used to improve future enzyme electrodes. This may be achieved through the novel use of biocompatible and biomimicking polymers, through simple biofuel cell fabrication and with the use of multi analyte biosensors developed during this investigation.
A microsomal membrane bound alcohol oxidase enzyme was isolated from a hydrocarbon degrading Aspergillus terreus fungus that could oxidize short chain-,long chain-, secondary-, and aryl-alcohol substrates. High aggregating property of the protein was demonstrated by AFM, DLS and TEM analyses. Chemical analysis showed the presence of oleic acid and palmitic acid at a ratio of 2:1 in the purified protein. We have demonstrated a highly efficient method for dissociation and simultaneous deflavination of the alcohol oxidase protein using ?-ME. The potential applications of this approach on preparing apoprotein and its reassemble with FAD to a functional enzyme are envisaged in the preparation of enzyme electrodes for biosensor and biofuel cell applications. The findings obtained through this investigation have revealed many interesting facts about this novel microsomal alcohol oxidase enzyme.This investigation has opened up new avenue on the research to explore the architecture of alcohol oxidase proteins from fungal sources including their structure-function relationship and potential applications.
Biosensor employing organelles in immobilized form are widely used in environmental monitoring. These immobilized organelles play vital role in sensitivity, accuracy, and stability of the biosensor system. Some of the organelle used for immobilization is whole cell, protein, enzyme and DNA. Traditionally biosensor used whole cell from one individual strain of microorganism. This concept limits the biosensor detection to certain specific samples alone. Detection of the content of the samples depends on the properties of the immobilized microbial cell. For detection of broad range of samples, novel biosenor using mixed microbial cultures is being designed in this dissertation.
Demand for biosensor research applications is growing steadily. According to a new report by Frost & Sullivan, the biosensor market is expected to reach $14.42 billion by 2016. Clinical diagnostic applications continue to be the largest market for biosensors, and this demand is likely to continue through 2016 and beyond. Biosensor technology for use in clinical diagnostics, however, requires translational research that moves bench science and theoretical knowledge toward marketable products. Despite the high volume of academic research to date, only a handful of biomedical devices have become viable commercial applications. Academic research must increase its focus on practical uses for biosensors. This book is an example of this increased focus, and discusses work to advance microfluidic-based protein biosensor technologies for practical use in clinical diagnostics.
Lignocellulosic Biomass Production and Industrial Applications describes the utilization of lignocellulosic biomass for various applications. Although there have been numerous reports on lignocellulosic biomass for biofuel application, there have been very few other applications reported for lignocellulosic biomass-based chemicals and polymers. Therefore, this book covers all of the possible lignocellulosic biomass applications. Besides describing the different types of biofuel production, such as bioethanol, biobutanol, biodiesel and biogas from lignocellulosic biomass, it also presents various other lignocellulosic biomass biorefinery applications for the production of chemicals, polymers, paper and bioplastics. In addition, there are chapters on valorization of lignocellulosic materials, alkali treatment to improve the physical, mechanical and chemical properties of lignocellulosic natural fibers, and a discussion of the major benefits, limitations and future prospects of the use of lignocellulosic biomass.
A new micro-fluidic biosensor array for fast online adherent cell monolayer analysis during cell proliferation and stimulation was developed. Quartz crystal resonators and impedimetric sensor responses were analysed by means of impedance spectroscopy. Time-lapse light microscopy was employed for visual characterization of the cells. Four independent units embedded within the same device allow parallelized cell cultivation. An external flow injection system provides automated and parallelized media feed as well as overpressure regime in the system. Thin-film deposition techniques were applied for sensors fabrication. New dedicated sensor interface electronics were developed to allow fast and parallelized spectra acquisition on 32 sensors. Madin-Darby Canine Kidney cells were cultivated in the biosensor array. The cell behavior during cell proliferation and stimulation was analyzed online. It is believed that in the future, the new biosensor array can be successfully employed as a tool supporting standard techniques employed in molecular cell biology for the study of that complex system of communication that governs basic cellular activities and coordinates cell actions.
Enzymes are versatile biocatalysts and find increasing applications in various industrial processes including organic synthesis and bioremediation. However, the application of enzymes is often limited by the short catalytic lifetime and by the difficulty in recovery and recycling. In this study, different types of nanostructured materials were used as hosts for enzyme immobilization since they provided a large surface area, leading to a higher volumetric enzyme activity. This work demonstrates that different types of nanostructured materials were efficiently used as hosts for enzyme immobilization. The synergy between various nanostructures and suitable immobilization methods including CLEA resulted in vivid improvements of catalytic features, therefore it offers great potential to expand to any other enzymes for the development of stable system in many enzymatic applications.
The concern about global warming effects by continuous exploitation of non renewable fossil fuels and scarcity of electricity generation accelerates the urge for searching alternative source of energy. Development of Microbial fuel cell using microbes present in waste water is the novel approach to treat this hurdle. Apart from biopower generation, it acts as a biosensor. Microbes metabolizes the organic matter present in waste water during the process electricity is generated. Within course of time the wastewater is treated with Chlorella vulgaris for the removal of phosphate for about 50 percent present in water. The amount of electricity generated has increased. The biomass thus produced, can be used for biofuel generation. For further purification of this treated wastewater, a novel method of treating it with Strychnos potatorum (chilla ginjalu) seeds is attempted.
Since 1980’s a large increase has occurred in the range of commercial fermented product, particularly secondary metabolites and recombination proteins. In the past, only the fermentation of extracellular enzyme, such as amylase and proteases, was industrially possible. Fed batch reactors are widely used in industrial applications because they combine the advantages from both batch and continuous process. The feed batch fermentation protocol proved effective with DNG/f.b-?ase19 microbial strain for the production of desired enzyme. The periodic incorporation of nitrogenous source enhances enzyme production logarithmically while the growth of the inoculant declined suggests the maturization of the cell and secondary metabolites nature of produced enzyme.
Advancements in the micro/nano-fabrication techniques have opened up new avenues for the development of portable and easier-to-use biosensors. Over the last few years, carbon electrodes have been widely used as sensing units in biosensors due to their attractive physiochemical properties. This book details different strategies to develop functionalized high surface carbon micro/nano-electrodes for electrochemical and biosensing devices. Carbon electrodes were fabricated via carbon-MEMS technique, which is based on pyrolyzing prepatterned photoresist. To increase the surface area of the carbon electrodes, multiple approaches such as (i) fabrication of porous 3D carbon microarrays, (ii) conformal coating of graphene onto 3D carbon microarrays, and (iii) fabrication of controllable carbon nanostructures were investigated. For carbon surface functionalization to covalently attach biomolecules, different oxidation techniques and the resultant surface carbon–oxygen groups were analyzed and compared. Lastly, label-free detection of platelet-derived growth factor oncoprotein, a cancer biomarker, was demonstrated on 3D carbon microarrays platform with sub-nanomolar detection limit.
The book gives an overview on the current development status of synthetic diamond films and their applications. Its initial part is devoted to discuss the different types of conductive diamond electrodes that have been synthesized, their preparation methods, and their chemical properties and characterization. The electrochemical properties of diamond films in different scientific areas, with special attention in electroanalysis, are further described. Different strategies to modify these electrodes are also discussed as important technologies with ability to change their electrochemical characteristics for a more specific electroanalytical use. The second part of the book deals with practical applications of diamond electrodes to the industry, organic electrosynthesis, electrochemical energy technology, and biotechnology. Special emphasis is made on the properties of these materials for the production of strong oxidizing species allowing the fast mineralization of organics and their use for water disinfection and decontamination. Recent biotechnological development on biosensors, microelectrodes, and nanostructured electrodes, as well as on neurochemistry, is also presented. The book will be written by a large number of internationally recognized experts and comprises 24 chapters describing the characteristics and theoretical fundaments of the different electrochemical uses and applications of synthetic diamond films.
Biomass is biodegradable, less CO2, CO, H2S, HC and NOX emissions as well as renewable energy resource for the creation of steam and electricity, transportation fuel, manufacturing industries as well as a solvent in the laboratory. Agricultural crops residues (biomass) have emerged as one of the promising sources for bioethanol production. Such an approach can contribute to solve major problems of air pollution resulting from green house gas emission evolution and future crisis due to the shortage of energy sources. The controlling factors that affect the production of bio-fuel (biodiesel and bioethanol) from biomass are described. The optimal value of the parameters such as temperature, pH, yeast and enzyme percent and fermentation period are found and explained. Different types of fuel cell and electricity generation were explained from different scientific sources. Nowadays biofuel as well as biofuel cell is an innovative and important energy source from biomass by which power can be generated both in transportation and electricity. Still no research work done in this regard except few demonstration. That is why, the scope of innovative bio-fuel cell for electricity generation.
Biofuel Crop Sustainability brings together the basic principles of agricultural sustainability and special stipulations for biofuels, from the economic and ecological opportunities and challenges of sustainable biofuel crop production to the unique characteristics of particular crops which make them ideal for biofuel applications. This book will be a valuable resource for researchers and professionals involved in biofuels development and production as well as agriculture industry personnel. Chapters focus the broad principles of resource management for ecological, environmental and societal welfare, the sustainability issues pertaining to several broad categories of biofuel crops , as well as the economics and profitability of biofuels on both a local and international scale. Coverage includes topics such as utilizing waste water for field crop irrigation and algae production, reliability of feedstock supply, marginal lands, and identifying crops with traits of significance for survival and growth on low fertility soils. The development of production practices with low external inputs of fertilizer, irrigation, and pesticides is also covered. Biofuel Crop Sustainability will be a valuable, up-to-date reference for all those involved in the rapidly expanding biofuels industry and sustainable agriculture research fields.
Metallic starch capped gold nanoparticles have been synthesized by the reduction of chloroaurate anions [AuCl4]- solution with hydrazine in the aqueous starch and ethylene glycol solution at room temperature and at atmospheric pressure. The characterization of synthesized gold nanoparticles by UV–Vis spectroscopy, Scanning electron microscopy (SEM), X-ray diffraction (XRD) indicate that average size of pure gold NPs is 5-10 nm, they are spherical in shape and are pure metallic gold. Starch capped gold nanoparticles along with tyrosinase enzyme are effectively entrapped within sol-gel matrix for application in catechol biosensor. Enzymatic reaction between tyrosinase and catechol results in the formation of a colored compound which shows characteristic absorbance at 410 nm. Starch@AuNPs based catechol biosensor showed fast response with linearity for catechol sensing from 1 to 5 mM. Effect of buffer pH and its concentration was also studied and results showed drastic changes in absorption intensity with pH and concentration variation. Along with catechol biosensor, starch capped gold NPs find their application in glucose, urease and peroxide biosensor, owing to their stability.
This study aimed to isolate, purify and characterize L-asparaginase present in some animal tissues. The L-asparaginase (EC 126.96.36.199) produced by chicken livers was isolated and characterized. Different purification steps (including ammonium sulphate fractionation followed by separation on Sephadex G-100 gel filtration and Sephadex G-200 gel filtration) were applied to crude filtrate to obtain a pure enzyme preparation. The enzyme was purified 128.5 ± 0.5 fold and showed a final specific activity of 158.11 ± 5.0 U/mg with a 17.1 ± 8.6 % yield. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) of the purified enzyme revealed it was one peptide chain with Mr of 33 kDa while by gel filtration appears to be 36 kDa. The enzyme was very specific to L-asparagine and did not hydrolyze L-glutamine. A Lineweaver-Burk analysis showed a Km value of 1.66 mM toward L-asparagine as substrate and Vmax of 34.47 U. The enzyme showed maximum activity at pH 11.0 when incubated at 60?C for 20 min. The amino acids composition of the purified enzyme was also determined. Antitumor activity was investigated. The enzyme inhibited the growth of the two human cell lines including hepatoc