Development of an amperometric, screen-printed, single-enzyme phosphate ion biosensor and its application to the analysis of biomedical and environmental samples

Jenkins, A. T.A.; Gilbert, L.; Hart, John P.; Browning, S.

Abstract

An amperometric phosphate biosensor, based on a cobalt phthalocyanine screen-printed carbon electrode (CoPC-SPCE) is described. The immobilisation of the enzyme pyruvate oxidase (PyOd) was investigated using pre-formed cellulose acetate/cellulose nitrate membranes, of different pore sizes, and the cross-linking agent, glutaraldehyde (GLA). The latter method was found to be superior in terms of performance characteristics and also ease of fabrication. A linear range of 2.5-130 μM and limit of detection of 2 μM was obtained under optimal conditions. The biosensor also exhibited an excellent response time of just 13 s ± 1, n = 3. The biosensor was successfully applied to the measurement of phosphate in pond water samples; the mean recovery of spiked water samples was 103.2%, n = 3. The original concentration of phosphate calculated in the water sample (48 μM) was found to be in good agreement with that found using a standard colourimetric method. In addition to the analysis of water samples the biosensor was also applied to the analysis of human urine, with only a simple dilution of the sample, directly into the electrochemical cell, required for analysis. The precision of the biosensors, obtained during the urine analysis was 6.4%, n = 6. © 2011 Elsevier B.V. All rights reserved.

• Journal Article Type: Article
• Publication Date: Dec 15, 2011
• Journal: Sensors and Actuators, B: Chemical
• Print ISSN: 0925-4005
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 160
• Issue: 1
• Pages: 1322-1327
• DOI: https://doi.org/10.1016/j.snb.2011.09.069
• Keywords: phosphate, biosensor, amperometric, screen-printed, water analysis, urine analysis
• Public URL: https://uwe-repository.worktribe.com/output/968432
• Publisher URL: http://dx.doi.org/10.1016/j.snb.2011.09.069