Limits...
Single-Stranded DNA Aptamers against Pathogens and Toxins: Identification and Biosensing Applications.

Hong KL, Sooter LJ - Biomed Res Int (2015)

Bottom Line: Molecular recognition elements (MREs) can be short sequences of single-stranded DNA, RNA, small peptides, or antibody fragments.There has been an increasing interest in the identification and application of nucleic acid molecular recognition elements, commonly known as aptamers, since they were first described in 1990 by the Gold and Szostak laboratories.Lastly, an overview of the basic principles of ssDNA aptamer-based biosensors is discussed.

View Article: PubMed Central - PubMed

Affiliation: Department of Basic Pharmaceutical Sciences, 1 Medical Center Drive, P.O. Box 9530, Morgantown, WV 20506, USA.

ABSTRACT
Molecular recognition elements (MREs) can be short sequences of single-stranded DNA, RNA, small peptides, or antibody fragments. They can bind to user-defined targets with high affinity and specificity. There has been an increasing interest in the identification and application of nucleic acid molecular recognition elements, commonly known as aptamers, since they were first described in 1990 by the Gold and Szostak laboratories. A large number of target specific nucleic acids MREs and their applications are currently in the literature. This review first describes the general methodologies used in identifying single-stranded DNA (ssDNA) aptamers. It then summarizes advancements in the identification and biosensing application of ssDNA aptamers specific for bacteria, viruses, their associated molecules, and selected chemical toxins. Lastly, an overview of the basic principles of ssDNA aptamer-based biosensors is discussed.

No MeSH data available.


Related in: MedlinePlus

Illustration of examples of ssDNA MRE based fluorescent biosensors. (a) A representation of the changes in fluorescent signal upon target binding to a fluorophore labeled MRE. (b) A representation of an “on-mode” system by using a quencher labeled on the complementary sequence.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4493287&req=5

fig4: Illustration of examples of ssDNA MRE based fluorescent biosensors. (a) A representation of the changes in fluorescent signal upon target binding to a fluorophore labeled MRE. (b) A representation of an “on-mode” system by using a quencher labeled on the complementary sequence.

Mentions: The principle of fluorescence detection is based on the generation or quenching of fluorescence signals upon target binding. Various fluorescence molecules and quantum dots can be linked to ssDNA MREs. Conformational changes induced by target binding can alter the fluorescence signal generated by the fluorophore and therefore can be measured (Figure 4) [264]. Quenching molecules can also be linked to the other end of the ssDNA MRE. In this system, the quencher completely blocks the fluorescence signal from the fluorophore and target binding can move the quencher away from the fluorophore and have “signal on” detection (Figure 4) [265]. The same principle can also be applied for a “signal off” system. Carbon nanotubes and graphene can also be used as quenchers, where fluorescent labeled ssDNA MREs is adsorbed on the carbon quenchers via π-π stacking interactions. Fluorescence resonance energy transfer (FRET) can also be utilized as measurements when the distance of the two fluorescence molecules linked to MREs is changed upon target binding.


Single-Stranded DNA Aptamers against Pathogens and Toxins: Identification and Biosensing Applications.

Hong KL, Sooter LJ - Biomed Res Int (2015)

Illustration of examples of ssDNA MRE based fluorescent biosensors. (a) A representation of the changes in fluorescent signal upon target binding to a fluorophore labeled MRE. (b) A representation of an “on-mode” system by using a quencher labeled on the complementary sequence.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4493287&req=5

fig4: Illustration of examples of ssDNA MRE based fluorescent biosensors. (a) A representation of the changes in fluorescent signal upon target binding to a fluorophore labeled MRE. (b) A representation of an “on-mode” system by using a quencher labeled on the complementary sequence.
Mentions: The principle of fluorescence detection is based on the generation or quenching of fluorescence signals upon target binding. Various fluorescence molecules and quantum dots can be linked to ssDNA MREs. Conformational changes induced by target binding can alter the fluorescence signal generated by the fluorophore and therefore can be measured (Figure 4) [264]. Quenching molecules can also be linked to the other end of the ssDNA MRE. In this system, the quencher completely blocks the fluorescence signal from the fluorophore and target binding can move the quencher away from the fluorophore and have “signal on” detection (Figure 4) [265]. The same principle can also be applied for a “signal off” system. Carbon nanotubes and graphene can also be used as quenchers, where fluorescent labeled ssDNA MREs is adsorbed on the carbon quenchers via π-π stacking interactions. Fluorescence resonance energy transfer (FRET) can also be utilized as measurements when the distance of the two fluorescence molecules linked to MREs is changed upon target binding.

Bottom Line: Molecular recognition elements (MREs) can be short sequences of single-stranded DNA, RNA, small peptides, or antibody fragments.There has been an increasing interest in the identification and application of nucleic acid molecular recognition elements, commonly known as aptamers, since they were first described in 1990 by the Gold and Szostak laboratories.Lastly, an overview of the basic principles of ssDNA aptamer-based biosensors is discussed.

View Article: PubMed Central - PubMed

Affiliation: Department of Basic Pharmaceutical Sciences, 1 Medical Center Drive, P.O. Box 9530, Morgantown, WV 20506, USA.

ABSTRACT
Molecular recognition elements (MREs) can be short sequences of single-stranded DNA, RNA, small peptides, or antibody fragments. They can bind to user-defined targets with high affinity and specificity. There has been an increasing interest in the identification and application of nucleic acid molecular recognition elements, commonly known as aptamers, since they were first described in 1990 by the Gold and Szostak laboratories. A large number of target specific nucleic acids MREs and their applications are currently in the literature. This review first describes the general methodologies used in identifying single-stranded DNA (ssDNA) aptamers. It then summarizes advancements in the identification and biosensing application of ssDNA aptamers specific for bacteria, viruses, their associated molecules, and selected chemical toxins. Lastly, an overview of the basic principles of ssDNA aptamer-based biosensors is discussed.

No MeSH data available.


Related in: MedlinePlus