Biology Reference
In-Depth Information
Capture probe (CP)
A specifically designed ssDNA with a defined
(known) nucleotide sequence usually immobilized on a transducer
or other surface. The CP is utilized as a recognition element to test
nucleotidesequenceoftargetDNA(tDNA)inthesamplesolutionby
using hybridization.
Chemical sensor
A device that converts chemical information
such as the presence/concentration of specific sample components
into a measurablel signal [66]. Chemical sensors contain two basic
functional units connected in a series: a chemical (molecular)
recognition system (receptor) and a physicochemical transducer
[6]. It is capable of continuously recognizing the presence and/or
concentration of a chemical constituent in a liquid or gas and
converting this information in real time to an electrical or optical
signal.
Chemically modified electrode
An electrode made of a conduct-
ing or semiconducting material that is coated with a selected
monomolecular, multimolecular, ionic, or polymeric film of a
chemical modifier and that by means of faradaic (charge transfer)
reactionsorinterfacialpotentialdifferences(nonetchargetransfer)
exhibits chemical, electrochemical, and/or optical properties of
the film [10, 11]. The chemically altered bare (working) electrode
exhibits new qualities concerning selectivity and sensitivity as well
as againstfouling and interferences.
Circular DNA
A structure of DNA when its double-helical segment
isclosed to a circle by joining itstwo ends.
DNA (deoxyribonucleic acid)
A polyanionic biopolymer consisting
ofachainofnucleotideslinkedwithphosphatesbridgeatthe3'and
5' positions of neighboring sugar (2-deoxyribose) units (ssDNA).
Complementary base pairing results in the specific association of
two polynucleotide chains that wind around a common helical axis
to forma doublehelix (dsDNA).
DNA-based biosensor
A biosensor that uses DNA as the biorecog-
nitionelement.
