7 research outputs found
Design, Development and Applications of Highly Sensitive Protein-Based Capacitive Biosensors
Highly sensitive biosensors were developed for environmental and medical applications. The biosensors were based on bioengineered proteins as biorecognition elements coupled to a highly sensitive capacitive transducer. Heavy metal binding proteins like the metallothionein SmtA, regulatory protein MerR, periplasmic protein MerP and the synthetic phytochelatin EC20 were used for designing, constructing, and characterising biosensors for the determination of various heavy metal ions, i.e. mercury, copper, cadmium, zinc and lead, in a wide concentration range (fM-mM). The developed heavy metal biosensors had a useful storage stability (about two weeks) and could be regenerated using EDTA. The developed and optimised biosensors were assessed in two practical applications, namely monitoring mercury ions in contaminated soil samples, and measuring inducer molecules. The SmtA based biosensor was successfully used to monitor heavy metals in soil samples originating from a contaminated agricultural site in Denmark. The obtained results were compared to those given by a bacterial biosensor, a plant sensor, and the total amount of mercury contained in the soil. Both the protein-based and the bacterial biosensor, proved to accurately monitor the ion content, giving results well in agreement with those shown by the total amount. By using the same sensing principle, biosensors based on lac repressor protein were developed for monitoring of different inducer molecules, e.g. IPTG, ONPG, and lactose, or DNA. The biosensor could differentiate between lac operator DNA contained in linearized plasmid DNA and circular plasmid DNA, and genomic DNA
Novel synthetic phytochelatin-based capacitive biosensor for heavy metal ion detection
A novel capacitance biosensor based on synthetic phytochelatins for sensitive detection of heavy metals is described. Synthetic phytochelatin (Glu-Cys)20Gly (EC20) fused to the maltose binding domain protein was expressed in Escherichia coli and purified for construction of the biosensor. The new biosensor was able to detect Hg2+, Cd2+, Pb2+, Cu2+ and Zn2+ ions in concentration range of 100 fMâ10 mM, and the order of sensitivity was SZn>SCu>SHg>>SCdSPb. The biological sensing element of the sensor could be regenerated using EDTA and the storage stability of the biosensor was 15 days
Biosensors for Detection of Mercury in Contaminated Soils
Biosensors based on whole bacterial cells and on bacterial heavy metal binding protein were used to determine the mercury
concentration in soil. The soil samples were collected in a vegetable garden accidentally contaminated with elemental mercury 25
years earlier. Bioavailable mercury was measured using diïŹerent sensors: a protein-based biosensor, a whole bacterial cell based
biosensor, and a plant sensor, i.e. morphological and biochemical responses in primary leaves and roots of bean seedlings grown in
the mercury-contaminated soil. For comparison the total mercury concentration of the soil samples was determined by AAS. Whole
bacterial cell and protein-based biosensors gave accurate responses proportional to the total amount of mercury in the soil samples.
On the contrary, plant sensors were found to be less useful indicators of soil mercury contamination, as determined by plant
biomass, mercury content of primary leaves and enzyme activities
Biosensors for detection of mercury in contaminated soils
Biosensors based on whole bacterial cells and on bacterial heavy metal binding protein were used to determine the mercury concentration in soil. The soil samples were collected in a vegetable garden accidentally contaminated with elemental mercury 25 years earlier. Bioavailable mercury was measured using different sensors: a protein-based biosensor, a whole bacterial cell based biosensor, and a plant sensor, i.e. morphological and biochemical responses in primary leaves and roots of bean seedlings grown in the mercury-contaminated soil. For comparison the total mercury concentration of the soil samples was determined by AAS. Whole bacterial cell and protein-based biosensors gave accurate responses proportional to the total amount of mercury in the soil samples. On the contrary, plant sensors were found to be less useful indicators of soil mercury contamination, as determined by plant biomass, mercury content of primary leaves and enzyme activities. (C) 2004 Elsevier Ltd. All rights reserved
Biosensors for life quality. Design, development and application
none10Biosensors, combining a selective biological recognition element and a sensitive transducer, are versatile analytical tools applied more
and more in different ïŹelds, such as medicine, food quality and safety control, and environment pollution monitoring. They are expected to
play an increasingly important role in the improvement of life quality. In this context, the present work covers recent approaches in design
and development of biosensors applied for analysis of real samples of medical, environmental or industrial relevance. The described sensors
meet the sensitivity, selectivity, and response time required by their applications. Moreover, they are designed to avoid contamination of the
monitored systems with undesirable components and to minimise the damage of living organisms (when it comes to in vivo monitoring).J. Castillo; S. Gåspår; S. Leth; M. Niculescu; A. Mortari; I. Bontidean; V. Soukharev; S.A. Dorneanu; A.D. Ryabov; E. CsöregiJ., Castillo; S., Gåspår; S., Leth; M., Niculescu; Mortari, Alessia; I., Bontidean; V., Soukharev; S. A., Dorneanu; A. D., Ryabov; E., Csöreg