Mercury film electrodes (MFE) have recently been used in nucleic acid electrochemical analysis as alternatives to the classical mercury drop ones. DNA modified with osmium tetroxide, 2,2'-bipyridine (Os,bipy) can be detected with a high sensitivity at mercury electrodes via measurements of a catalytic osmium signal. In this paper we show that mercury film on a glassy carbon electrode can be used in voltammetric analysis of Os,bipy-modified DNA. Application of the MFE as a detection electrode in double-surface electrochemical DNA hybridization assay involving osmium labeling of target DNA is demonstrated.

• MeSH
• 2,2'-dipyridyl analogy a deriváty   analýza   chemie   MeSH
• barvení a značení metody   MeSH
• biokompatibilní potahované materiály chemie   MeSH
• biosenzitivní techniky metody   MeSH
• DNA sondy chemie   MeSH
• DNA analýza   chemie   MeSH
• elektrochemie metody   MeSH
• elektrody * MeSH
• hybridizace nukleových kyselin metody   MeSH
• organokovové sloučeniny analýza   chemie   MeSH
• rtuť chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• validační studie MeSH
• Názvy látek
• 2,2'-dipyridyl MeSH
• biokompatibilní potahované materiály MeSH
• calf thymus DNA MeSH Prohlížeč
• DNA sondy MeSH
• DNA MeSH
• organokovové sloučeniny MeSH
• osmium tetroxide-2,2'-bipyridine MeSH Prohlížeč
• rtuť MeSH

Osmium tetroxide complexes with nitrogen ligands (L) are probes of DNA structure and electroactive labels of DNA. Here adducts of single-stranded (ss) DNA with osmium tetroxide 2,2'-bipyridine (DNA-Os,bipy) were studied by cyclic voltammetry for the first time. It was found that at neutral pH DNA-Os,bipy produces three redox couples in the potential range between 0 and -1 V (peaks I-III) and a cathodic peak at about -1.3 V (peak IV). The latter peak decreased with increasing scan rate, and peaks arising from the forward and reverse scans exhibited the same direction, suggesting catalytic nature of the electrode process. We concluded that this peak corresponds to the known differential pulse voltammetric (polarographic) peak of DNA-Os,L adducts for which catalytic hydrogen evolution is responsible. In contrast, currents of cathodic peaks II and III increased almost linearly with increasing scan rate, suggesting involvement of adsorption in the electrode processes. Adsorptive stripping square-wave voltammetry was used to analyze the DNA-Os,bipy at low concentrations. It was shown that at neutral pH, peak III can offer sensitivity in the ppb range, which is only little lower than that reached by catalytic peak IV. The latter peak is, however, superior in sensitivity at acid pH values.

• MeSH
• 2,2'-dipyridyl analogy a deriváty   analýza   chemie   MeSH
• barvení a značení metody   MeSH
• biokompatibilní potahované materiály chemie   MeSH
• biosenzitivní techniky metody   MeSH
• DNA sondy chemie   MeSH
• DNA analýza   chemie   MeSH
• elektrochemie metody   MeSH
• elektrody * MeSH
• hybridizace nukleových kyselin metody   MeSH
• organokovové sloučeniny analýza   chemie   MeSH
• rtuť chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• 2,2'-dipyridyl MeSH
• biokompatibilní potahované materiály MeSH
• calf thymus DNA MeSH Prohlížeč
• DNA sondy MeSH
• DNA MeSH
• organokovové sloučeniny MeSH
• osmium tetroxide-2,2'-bipyridine MeSH Prohlížeč
• rtuť MeSH