| 1. |
- ALCOCK, SJ, et al.
(author)
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Continuous analyte monitoring to aid clinical practice
- 1994
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In: IEEE Engineering in Medicine and Biology Magazine. - : IEEE; 1999. - 0739-5175 .- 1937-4186. ; 13:3, s. 319-325
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Journal article (peer-reviewed)abstract
- Considerable progress has been made in the development of practical glucose sensors for in vivo use. In some designs, the sensor can be replaced by the patient, who "injects" a new sensor into a fresh site using a hypodermic needle. An open-loop hypoglycaemia sensor providing an alarm signal could be available soon, and it would be very useful in the management of diabetes. The sensor for this application would need to function for a minimum period of about 12 hours. Further developments in the glucose sensor area are expected to lead to a comfortable implantable sensor/pump device, which would provide closed loop control for a prolonged period. An acceptable system would be a sensor replaced every 2 to 3 days, coupled with a microprocessor-controlled pump replaced after 2 to 3 years. Further engineering input is needed to design the monitoring and control unit containing the alarm and pump systems. The world market in clinical analysis is about US $6 billion, and covers about 10% of the total expenses for health care. It is in the field of continuous microsensors that future competition for the clinical diagnostic market will take place. Funding in vivo projects is less attractive to industry than the more proven and well-established area of in vitro diagnostics. However, the benefits of in vivo monitoring to the health of the community, and the financial rewards to manufacturers are ultimately great. It is clearly of interest for industry to invest in the development and commercialisation of this high added-value technology.
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| 2. |
- ALCOCK, SJ, et al.
(author)
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THE DESIGN AND DEVELOPMENT OF NEW CHEMICAL SENSORS FOR INVIVO MONITORING
- 1991
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In: Biosensors & bioelectronics. - : Elsevier Science B.V., Amsterdam.. - 0956-5663 .- 1873-4235. ; 6:8, s. 647-652
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Journal article (peer-reviewed)abstract
- The latest workshop of the European Community (EC) Concerted Action on Chemical sensors for in vivo monitoring was held in Nauplion, Greece, in April this year. This fifth workshop focused on The design and development of new sensors for in vivo monitoring, and was organized into five sessions: design and development of new sensors; operational considerations; performance of analytical systems; novel sensors/tissue heterogeneity; and infra-red spectroscopy.
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| 3. |
- BIFULCO, L, et al.
(author)
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TTF-MODIFIED BIOSENSORS FOR HYDROGEN-PEROXIDE
- 1994
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In: Analytical Letters. - : Taylor andamp;amp; Francis. - 0003-2719 .- 1532-236X. ; 27:8, s. 1443-1452
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Journal article (peer-reviewed)abstract
- Amperometric biosensors for hydrogen peroxide were produced, based on TTF-modified graphite disc electrodes, incorporating immobilised peroxidase. At the optimum operating potential (-200 mV vs. calomel electrode), a Linear response to hydrogen peroxide was obtained in the range 0-2 mM (Km value = 1.98 mM). Low sensitivity to pH fluctuations and good stability at room temperature were exhibited.
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| 4. |
- BROOKS, SL, et al.
(author)
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BIOSENSORS FOR PROCESS-CONTROL
- 1991
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In: Enzyme and microbial technology. - : Elsevier Science B.V., Amsterdam.. - 0141-0229 .- 1879-0909. ; 13:12, s. 946-955
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Research review (peer-reviewed)abstract
- Biosensors have been extensively studied during the last 20 years, and a myriad of laboratory biosensors have been developed. Improvements are required in biosensor design and performance before they become widely accepted in industrial process monitoring. However, as the biotechnology industry expands, biosensors may become more acceptable because, despite their limitations, they are the only devices capable of delivering the information required.
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| 5. |
- DICKS, JM, et al.
(author)
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THE APPLICATION OF FERROCENE-MODIFIED N-TYPE SILICON IN GLUCOSE BIOSENSORS
- 1993
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In: Electroanalysis. - : John Wiley andamp;amp; Sons, Ltd. - 1040-0397 .- 1521-4109. ; 5:1
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Journal article (peer-reviewed)abstract
- This article describes the application of ferrocene-modified n-type silicon electrodes to the anaerobic redox catalysis of glucose oxidase. The electrodes are modified with ferrocene either directly, by using (1,1-ferrocenediyl)dichlorosilane, or via an underlying polypyrrole film. Light-activated catalytic waves are detected in both cases in the presence of glucose oxidase and glucose, thereby demonstrating rapid heterogeneous kinetics between the covalently immobilized mediator and glucose oxidase. A glucose-sensitive electrode is made by simple adsorption of glucose oxidase from an aqueous buffered solution into the surface film.
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| 6. |
- ERASIN, BR, et al.
(author)
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A FIXED-FILM BIOASSAY FOR THE DETECTION OF MICROPOLLUTANTS TOXIC TO ANAEROBIC SLUDGES
- 1994
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In: Analytica Chimica Acta. - : Elsevier Science B.V., Amsterdam.. - 0003-2670 .- 1873-4324. ; 298:1
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Journal article (peer-reviewed)abstract
- Micropollutants in waste water streams can be a serious problem for the anaerobic digestion process. A short-term acute bioassay system is described for testing the effects of new and potentially toxic compounds on anaerobic digestion processes. Change in methanogenic activity was used as the monitored process parameter and the performance of intoxicated inocula was compared to activity prior to adding test compounds and to the activity of a parallel control assay. The performance of the bioassay was tested with chlorinated solvents and heavy metals. Trichloroethane caused a 50% reduction in methanogenic activity at 7 mg/l assay. The performance of suspended and fixed biomass assays were compared; the suspended growth was found to be five times more sensitive to trichloroethane. There was no clear inhibition with the heavy metals even at the highest concentration used (up to 750 mg Cu/l). The duration of assay was found to be an important parameter in the evaluation of anaerobic toxicity.
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| 7. |
- HALL, GF, et al.
(author)
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AN ORGANIC-PHASE ENZYME ELECTRODE FOR CHOLESTEROL
- 1991
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In: Analytical Letters. - : Taylor andamp;amp; Francis. - 0003-2719 .- 1532-236X. ; 24:8, s. 1375-1388
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Journal article (peer-reviewed)abstract
- An enzyme electrode is described for the determination of cholesterol dissolved in chloroform/hexane (1:1). The enzyme electrode is shown to be applicable to the determination of cholesterol in samples of butter and margarine.
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| 8. |
- HALL, GF, et al.
(author)
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ELECTRON-TRANSFER FROM DIAPHORASE IN WATER TRITON X-100 BUTYL ACETATE MICROEMULSION
- 1994
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In: Electroanalysis. - : John Wiley andamp;amp; Sons, Ltd. - 1040-0397 .- 1521-4109. ; 6:3, s. 217-220
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Journal article (peer-reviewed)abstract
- The transfer of electrons from an enzyme in a microemulsion system to a glassy carbon electrode, via mediators of different solubilities, is demonstrated. A bienzymic reaction is carried out in a microemulsion formed by the nonionic detergent Triton X-100 in butyl acetate. The enzymes used are alcohol dehydrogenase (ADH, EC 1.1.1.1) and diaphorase (EC 1.8.1.4). ADH catalyzes the conversion of primary alcohols to aldehydes with the concomitant reduction of its cofactor. nicotinamide adenine dinucleotide (NAD-) to NADH. Diaphorase reoxidizes NADH and can utilize a variety of molecules as an electron acceptor. It is demonstrated that these may be water soluble or solvent soluble.
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| 9. |
- HENDRY, SP, et al.
(author)
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POLYFERROCENES AS MEDIATORS IN AMPEROMETRIC BIOSENSORS FOR GLUCOSE
- 1993
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In: Analytica Chimica Acta. - : Elsevier Science B.V., Amsterdam.. - 0003-2670 .- 1873-4324. ; 281:3, s. 453-459
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Journal article (peer-reviewed)abstract
- This paper describes the first successful application of polymeric ferrocenes as mediators in amperometric biosensors. The results have implications for the design of stable biosensors and bioelectronic devices involving electron transfer from oxidoreductases to electrode surfaces. The behaviour of two ferrocene polymers in enzyme electrodes was explored and a distinctive pH profile was noted. It is suggested that changes in either the enzyme conformation or the polymer in response to hydrogen ion concentration may explain the difference in behaviour between monomeric and polymeric ferrocenes.
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| 10. |
- HU, J, et al.
(author)
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AN ENZYME ELECTRODE FOR GLUCOSE CONSISTING OF GLUCOSE-OXIDASE IMMOBILIZED AT A BENZOQUINONE-MODIFIED CARBON ELECTRODE
- 1991
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In: Analytical Letters. - : Taylor andamp;amp; Francis. - 0003-2719 .- 1532-236X. ; 24:1, s. 15-24
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Journal article (peer-reviewed)abstract
- This paper describes an amperometric enzyme electrode for the analysis of glucose. The glucose sensor utilised adsorbed benzoquinone on a carbon electrode to mediate electron transfer from glucose oxidase. A linear response to 0-15 mM glucose was observed. The electrodes response to glucose, its pH profile and the effect of temperature are presented.
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