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 colorimetric biosensors. (a) A representation of a colorimetric assay using MRE dispersed gold nanoparticles. (b) A representation of a colorimetric assay using cross-linked gold nanoparticles aggregates via MRE and probe DNA.
© Copyright Policy
Related In: Results  -  Collection

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

fig5: Illustration of examples of ssDNA MRE based colorimetric biosensors. (a) A representation of a colorimetric assay using MRE dispersed gold nanoparticles. (b) A representation of a colorimetric assay using cross-linked gold nanoparticles aggregates via MRE and probe DNA.

Mentions: Gold nanoparticles (AuNP) have been widely used in various colorimetric assays. AuNPs aggregate in salt solution and appear in purple color. When they are dispersed, they are in red color. This special absorbance property of AuNPs allows observation of target binding by naked eye. MREs in salt solution can bind to AuNPs, dispersing the AuNPs. When targets are introduced into the system, MRE preferably bind to the targets, therefore causing AuNPs to aggregate, and a red to purple color change is observed (Figure 5) [266]. Alternatively, ssDNA MREs can be used to link AuNPs that are functionalized with probe strands. In this case, the initial state of the MRE/AuNPs solution is aggregated purple. Upon target binding, the linked AuNPs are released, and a purple to red color change is observed (Figure 5) [267]. Furthermore, AuNPs can be used in a sandwich colorimetric assay, in which the secondary reporting MRE linked AuNP can grow in size when the detection system is placed in a growth solution containing HAuCl4, thus enhancing the detection limit [268].


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 colorimetric biosensors. (a) A representation of a colorimetric assay using MRE dispersed gold nanoparticles. (b) A representation of a colorimetric assay using cross-linked gold nanoparticles aggregates via MRE and probe DNA.
© Copyright Policy
Related In: Results  -  Collection

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

fig5: Illustration of examples of ssDNA MRE based colorimetric biosensors. (a) A representation of a colorimetric assay using MRE dispersed gold nanoparticles. (b) A representation of a colorimetric assay using cross-linked gold nanoparticles aggregates via MRE and probe DNA.
Mentions: Gold nanoparticles (AuNP) have been widely used in various colorimetric assays. AuNPs aggregate in salt solution and appear in purple color. When they are dispersed, they are in red color. This special absorbance property of AuNPs allows observation of target binding by naked eye. MREs in salt solution can bind to AuNPs, dispersing the AuNPs. When targets are introduced into the system, MRE preferably bind to the targets, therefore causing AuNPs to aggregate, and a red to purple color change is observed (Figure 5) [266]. Alternatively, ssDNA MREs can be used to link AuNPs that are functionalized with probe strands. In this case, the initial state of the MRE/AuNPs solution is aggregated purple. Upon target binding, the linked AuNPs are released, and a purple to red color change is observed (Figure 5) [267]. Furthermore, AuNPs can be used in a sandwich colorimetric assay, in which the secondary reporting MRE linked AuNP can grow in size when the detection system is placed in a growth solution containing HAuCl4, thus enhancing the detection limit [268].

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