Disposable genosensor, a new tool for the detection of NOS-terminator, a genetic element present in GMOs B. Meric et al. / Food Control 15 (2004) 621–626 zGenetically modified organisms (GMOs) are referred to as living organisms of vegetable or animal origin in which the artificial introduction of foreign genes is able to confer novel characteristics not found in the wild type. The EU Council regulation on traceability and labeling for GMO - A threshold of 0.9% is set for labeling, below which labeling of GMOs is not required. z PCR methods, based on exponential amplification of a specific GMO DNA fragment , are highly sensitive, but require sophisticated instruments for post-amplification steps, such as gel electrophoresis and fluorescent imaging. - Alternatively an electrochemical genosensor is presented here for rapid analysis of GMO related PCR products. Since GMOs and their derivatives are widely used in food industry, the analytical assays are needed to provide the detection and the quanti.cation of GMOs in food matrices zNos terminator is present in nearly all GMOs due to its important in gene regulation zDNA extraction and PCR was performed. zFrom the amplification of the NOS-terminator region,fragments of 180 bp (base pairs) were obtained . Probe 5`-AAT GAT TAA TTG GGG GAC TCT AAT C-3’ Target 5’-GAT TAG AGT CCC CCA ATT AAT CAT T-3’ Carbon Carbon Nanotubes Nanotubes (CNT) (CNT) z Multi walled carbon nanotubes (MWNTs) were used as nanowires which combined DNA molecules to a carbon paste electrode(CPE) z Unique electronic and mechanical properties and chemical stability z CNT accelerate the electron transfer Thymine probe: 5’-Amino-TTT TTT-3’ Adenine probe: 5’-Amino-AAA AAA-3’ Inosine substituted thymine tagged probe: 5’-TTT TTTCAA IAC CAC CAC TTC IAA ACC-3’ Target: 5’-GGT TTC GAA GTG GTG GTC TTG-3’ Single-base mismatch: 5’-GGT TTC GAA GGG GTG GTC TTG-3’ DNA DNA - - Directed Attachment of Carbon Directed Attachment of Carbon Nanotubes Nanotubes for Enhanced for Enhanced Label Label - - Free Electrochemical Detection of DNA Hybridization Free Electrochemical Detection of DNA Hybridization Electroanalysis Electroanalysis DOI: 10.1002/elan.200303025 DOI: 10.1002/elan.200303025 Electrochemical Coding of Single-Nucleotide Polymorphisms By Monobase-Modified Gold Nanoparticles Anal. Chem.2004, 76,1877-1884 . GTC TTG-3’ DNA DNA - - Directed Attachment of Carbon Directed Attachment of Carbon Nanotubes Nanotubes for Enhanced for Enhanced Label Label - - Free Electrochemical Detection of DNA Hybridization Free. Chem.20 04, 76,1877-18 84