Biosensor-based on-site explosives detection using aptamers as recognition elements

• Published in: Analytical and bioanalytical chemistry 2008-07, Vol.391 (5), p.1793-1800
• Main Authors: Ehrentreich-Förster, Eva, Orgel, Dagmar, Krause-Griep, Andrea, Cech, Birgit, Erdmann, Volker A, Bier, Frank, Scheller, F. W, Rimmele, Martina
• Format: Article
• Language: English
• Subjects: Analytical Chemistry; Aptamer; Aptamers, Nucleotide - chemistry; Biochemistry; Biosensing Techniques - instrumentation; Biosensing Techniques - methods; Biosensor; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Explosive Agents - analysis; Fiber Optic Technology - instrumentation; Fiber Optic Technology - methods; Food Science; In-field measurement; Laboratory Medicine; Ligands; Monitoring/Environmental Analysis; Original Paper; Reproducibility of Results; Sensitivity and Specificity; Spectrometry, Fluorescence - methods; Time Factors; TNT; Trinitrotoluene - analysis
• ISSN: 1618-2642; 1618-2650
• DOI: 10.1007/s00216-008-2150-5

Reliable observation, detection and characterisation of polluted soil are of major concern in regions with military activities in order to prepare efficient decontamination. Flexible on-site analysis may be facilitated by biosensor devices. With use of fibre-optic evanescent field techniques, it has been shown that immunoaffinity reactions can be used to determine explosives sensitively. Besides antibodies as molecular recognition elements, high-affinity nucleic acids (aptamers) can be employed. Aptamers are synthetically generated and highly efficient binding molecules that can be derived for any ligand, including small organic molecules like drugs, explosives or derivatives thereof. In this paper we describe the development of specific aptamers detecting the explosives molecule TNT. The aptamers are used as a sensitive capture molecule in a fibre-optic biosensor. In addition, through the biosensor measurements the aptamers could be characterised. The advantages of the aptamer biosensor include its robustness, its ability to discriminate between different explosives molecules while being insensitive to other chemical entities in natural soil and its potential to be incorporated into a portable device. Results can be obtained within minutes. The measurement is equally useful for soil that has been contaminated for a long time and for urgent hazardous spills.