Aptamer-DNAzyme hairpins for amplified biosensing.
Engineered nucleic acid hairpin structures are used for the amplified analysis of low-molecular-weight substrates (adenosine monophosphate, AMP) or proteins (lysozyme). The hairpin structures consist of the anti-AMP or antilysozyme aptamer units linked to the horseradish peroxidase (HRP)-mimicking DNAzyme sequence. The HRP-mimicking DNAzyme sequence is protected in a "caged", inactive structure in the stem regions of the respective hairpins, whereas the loop regions include a part of the respective aptamer sequence. The opening of the hairpins by the analytes, AMP or lysozyme, through the formation of the respective analyte-aptamer complexes, results in the self-assembly of the active HRP-mimicking DNAzyme. The DNAzyme catalyzes the H(2)O(2)-mediated oxidation of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(2-)) to the colored ABTS(*-), thus providing the amplified optical detection of the respective analytes. The engineered aptamer-DNAzyme hairpin structures reveal significantly improved analytical performance, as compared to analogous fluorophore-quencher-labeled hairpins.
Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, 91904 Israel.
Carsten
C
Teller
Simcha
S
Shimron
Itamar
I
Willner
D000249:Adenosine Monophosphate / Q000737:chemistry; D052157:Aptamers, Nucleotide / Q000737:chemistry*; D052160:Benzothiazoles / Q000737:chemistry; D015374:Biosensing Techniques / Q000379:methods*; D021881:DNA, Catalytic / Q000737:chemistry / Q000378:metabolism*; D006735:Horseradish Peroxidase / Q000737:chemistry / Q000378:metabolism; D009113:Muramidase / Q000737:chemistry; D013451:Sulfonic Acids / Q000737:chemistry
D052157:Aptamers, Nucleotide; D052160:Benzothiazoles; D021881:DNA, Catalytic; D013451:Sulfonic Acids; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; D000249:Adenosine Monophosphate; D006735:Horseradish Peroxidase; D009113:Muramidase