Biomedical subjects

Dilek Odaci

Publications and source records attributed to Dilek Odaci.

3 recordsLinked to original sources

PubMed2006

Graphite epoxy composite electrodes modified with bacterial cells.

The modification of a graphite-epoxy composite electrode (GECE) with bacterial cells along with an analytical application are presented. Pseudomonas putida DSM 50026 was used as a biological component and the measurement was based on the respiratory activity of the cells. The optimization of working conditions of resulting biosensor (including pH and temperature) was conducted and the limit of detection was calculated as 7 microM phenol based on the signal to noise ratio. Then the system was applied for xenobiotic detection. Resulting sample signals were found to be very similar with the standard solutions having the same concentration while the recoveries of the spiked samples were close to 100%.

Biosensing Techniques↗

PubMed2006

Effects of mediators on the laccase biosensor response in paracetamol detection.

An enzyme electrode suitable for paracetamol detection was developed by immobilizing laccase on a dissolved-oxygen probe surface. The immobilization procedure was achieved by means of gelatin, which was then cross-linked with glutaraldehyde. The measurement was based on the detection of oxygen consumption in relation to analyte oxidation. The optimum experimental conditions for the biosensor were investigated and the system was calibrated for paracetamol. Also the effects of three different mediators, namely HBT (1-hydroxybenzotriazole), VLA [violuric acid (5-isonitrosobarbituric acid)] and TEMPO (2,2',6,6'-tetramethylpiperidine-N-oxyl radical) were tested for the biosensor's response. As a result, it was observed that HBT has a remarkable effect on the signal by providing more oxygen consumption during the enzymatic reaction. A linear relationship between sensor responses and analyte concentrations was obtained over the concentration range 2.0-15.0 microM, whereas, in the presence of the mediator HBT, this range became 0.5-3.0 microM.

Acetaminophen↗

PubMed2004

Immobilized jerusalem artichoke (Helianthus tuberosus) tissue electrode for phenol detection.

A tissue based biosensor for the determination of phenol was developed by using Jerusalem artichoke (Helianthus tuberosus) in combination with a dissolved oxygen (DO) probe. The tissue electrode response depends linearly on phenol concentration between 0.002 and 0.0101 microM in 10 min response time. Maximum electrode response was found in phosphate buffer at pH 8.0 and 35 degrees C. The reproducibility of the enzyme electrode was also tested by using standard phenol solutions (0.005 microM). The standard deviation (SD) and variation coefficient (cv) were calculated as +/- 1.4 x 10(-4) microM and 3.1%, respectively.

Biosensing Techniques↗