uu.seUppsala University Publications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Investigation of Immobilization of Functionalized Magnetic Nanobeads in Rolling CircleAmplified DNA Coils
Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Genetics and Pathology.
Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Genetics and Pathology.
Show others and affiliations
2010 (English)In: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 114, no 10, 3707-3713 p.Article in journal (Refereed) Published
Abstract [en]

Immobilization characteristics for single-stranded oligonucleotide- functionalized magnetic beads with nominal sizes of 40, 80, 130, and 250 nm in rolling circle amplified (RCA) DNA coils is investigated by employing complex magnetization measurements, dynamic light scattering and fluorescence microscopy. It was found that larger beads in a polydisperse bead size distribution more easily immobilize in the RCA DNA coils than do smaller beads. This may be related to a higher oligonucleotide surface coverage for the larger beads. Furthermore, it was concluded that both bead size and oligonucleotide surface coverage determine whether beads immobilize to give isolated coils with beads or larger clusters of beads and coils. A small bead size and a low oligonucleotide surface coverage favor the first kind of immobilization behavior, whereas a large bead size and a high oligonucleotide surface coverage favor the other. The present findings could be used to optimize both size and surface functionalization of beads employed in substrate-free magnetic biosensors.

Place, publisher, year, edition, pages
2010. Vol. 114, no 10, 3707-3713 p.
National Category
Engineering and Technology
Research subject
Engineering Science with specialization in Nanotechnology and Functional Materials
Identifiers
URN: urn:nbn:se:uu:diva-120765DOI: 10.1021/jp911251kISI: 000275328400037PubMedID: 20175549OAI: oai:DiVA.org:uu-120765DiVA: diva2:303965
Available from: 2010-03-16 Created: 2010-03-16 Last updated: 2017-12-12Bibliographically approved
In thesis
1. Detection of Biomolecules Using Volume-Amplified Magnetic Nanobeads
Open this publication in new window or tab >>Detection of Biomolecules Using Volume-Amplified Magnetic Nanobeads
2012 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

This thesis describes a new approach to biomolecular analysis, called the volume-amplified magnetic nanobead detection assay (VAM-DNA). It is a sensitive, specific magnetic bioassay that offers a potential platform for the development of low-cost, easy-to-use diagnostic devices. The VAM-NDA consists of three basic steps: biomolecular target recognition, enzymatic amplification of the probe-target complex using the rolling circle amplification (RCA) technique, and addition of target complementary probe-tagged magnetic nanobeads which exhibit Brownian relaxation behavior. Target detection is demonstrated by measuring the frequency-dependent complex magnetization of the magnetic beads. The binding of the RCA products (target DNA-sequence coils) to the bead surface causes a dramatic increase in the bead size, corresponding essentially to the size of the DNA coil (typically around one micrometer). This causes a decrease in the Brownian relaxation frequency, since it is inversely proportional to the hydrodynamic size of the beads. The concentration of the DNA coils is monitored by measuring the decrease in amplitude of the Brownian relaxation peaks of free beads.

The parameters oligonucleotide surface coverage, bead concentration, bead size and RCA times were investigated in this thesis to characterize features of the assay. It was found that all of these parameters affect the outcome and efficiency of the assay.

The possibility of implementing the assay on a portable, highly sensitive AC susceptometer platform was also investigated. The performance of the assay under these circumstances was compared with that using a superconducting quantum interference device (SQUID); the sensitivity of the assay was similar for both platforms. It is concluded that, the VAM-NDA opens up the possibility to perform biomolecular detection in point-of-care and outpatient settings on portable platforms similar to the one tested in this thesis.

Finally, the VAM-NDA was used to detect Escherichia coli bacteria and the spores of Bacillus globigii, the non-pathogenic simulant of Bacillus anthracis. A limit of detection of at least 50 bacteria or spores was achieved. This shows that the assay has great potential for sensitive detection of biomolecules in both environmental and biomedical applications.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2012. 65 p.
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 905
Keyword
Magnetic biosensor, magnetic nanobeads, Brownian relaxation, padlock probe, rolling circle amplification, DNA detection, protein detection
National Category
Nano Technology
Research subject
Engineering Science with specialization in Nanotechnology and Functional Materials
Identifiers
urn:nbn:se:uu:diva-169431 (URN)978-91-554-8288-6 (ISBN)
Public defence
2012-04-13, Å 2005, Ångströmlaboratoriet, Lägerhyddsvägen 1, Uppsala, 09:30 (English)
Opponent
Supervisors
Available from: 2012-03-23 Created: 2012-02-29 Last updated: 2012-03-29Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textPubMed

Authority records BETA

Zardán Gómez de la Torre, TeresaStrömberg, MattiasRussell, CamillaNilsson, MatsSvedlindh, PeterStrømme, Maria

Search in DiVA

By author/editor
Zardán Gómez de la Torre, TeresaStrömberg, MattiasRussell, CamillaNilsson, MatsSvedlindh, PeterStrømme, Maria
By organisation
Nanotechnology and Functional MaterialsDepartment of Genetics and PathologySolid State Physics
In the same journal
Journal of Physical Chemistry B
Engineering and Technology

Search outside of DiVA

GoogleGoogle Scholar

doi
pubmed
urn-nbn

Altmetric score

doi
pubmed
urn-nbn
Total: 1104 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf