Novel Metal Clusters for Imaging Applications

Handle URI:
http://hdl.handle.net/10754/313850
Title:
Novel Metal Clusters for Imaging Applications
Authors:
Alsaiari, Shahad K.
Abstract:
During the past few years, gold nanoparticles (AuNPs) have received considerable attention in many fields due to their optical properties, photothermal effect and biocompatibility. AuNPs, particularly AuNCs and AuNRs, exhibit great potential in diagnostics and imaging. In the present study, AuNCs were used to selectively image and quantify intracellular antioxidants. It was reported by Chen et al. that the strong fluorescence of AuNCs is quenched by highly reactive oxygen species (hROS). Most of applications depend on fluorescence quenching, however, for our project we designed turn-on fluorescent sensors using AuNCs that sense antioxidants. In the presence of antioxidants, AuNCs fluorescence switch on, while in the absence of antioxidants their fluorescence immediately turn off due to hROS effect. AuNRs were also used for cellular imaging in which AuNRs were conjugated to Cy3-labelled molecular beacon (MB) DNA. Next, the previous complex was loaded in two different strains of magnetotactic bacteria (MTB). MTB were used as a targeted delivery vehicle in which magnetosomes direct the movement of bacteria. The DNA sequence was specific to a certain sequence in mitochondria. The exposure of MTB to an alternating magnetic field (AMF) leads to the increase of temperature inside the bacteria, which destruct the cell wall, and hence, bacterial payload is released. When MD-DNA hybrid with the target sequence, AuNR and Cy3 separate from each other, the fluorescence of the Cy3 is restored.
Advisors:
Khashab, Niveen M.
Committee Member:
Merzaban, Jasmeen ( 0000-0002-7276-2907 ) ; Pain, Arnab ( 0000-0002-1755-2819 )
KAUST Department:
Biological and Environmental Sciences and Engineering (BESE) Division
Program:
Bioscience
Issue Date:
May-2014
Type:
Thesis
Appears in Collections:
Bioscience Program; Theses; Biological and Environmental Sciences and Engineering (BESE) Division

Full metadata record

DC FieldValue Language
dc.contributor.advisorKhashab, Niveen M.en
dc.contributor.authorAlsaiari, Shahad K.en
dc.date.accessioned2014-03-10T13:30:53Z-
dc.date.available2014-03-10T13:30:53Z-
dc.date.issued2014-05en
dc.identifier.urihttp://hdl.handle.net/10754/313850en
dc.description.abstractDuring the past few years, gold nanoparticles (AuNPs) have received considerable attention in many fields due to their optical properties, photothermal effect and biocompatibility. AuNPs, particularly AuNCs and AuNRs, exhibit great potential in diagnostics and imaging. In the present study, AuNCs were used to selectively image and quantify intracellular antioxidants. It was reported by Chen et al. that the strong fluorescence of AuNCs is quenched by highly reactive oxygen species (hROS). Most of applications depend on fluorescence quenching, however, for our project we designed turn-on fluorescent sensors using AuNCs that sense antioxidants. In the presence of antioxidants, AuNCs fluorescence switch on, while in the absence of antioxidants their fluorescence immediately turn off due to hROS effect. AuNRs were also used for cellular imaging in which AuNRs were conjugated to Cy3-labelled molecular beacon (MB) DNA. Next, the previous complex was loaded in two different strains of magnetotactic bacteria (MTB). MTB were used as a targeted delivery vehicle in which magnetosomes direct the movement of bacteria. The DNA sequence was specific to a certain sequence in mitochondria. The exposure of MTB to an alternating magnetic field (AMF) leads to the increase of temperature inside the bacteria, which destruct the cell wall, and hence, bacterial payload is released. When MD-DNA hybrid with the target sequence, AuNR and Cy3 separate from each other, the fluorescence of the Cy3 is restored.en
dc.language.isoenen
dc.subjectAntioxidantsen
dc.subjectGold Nanoclustersen
dc.subjectGlutathioneen
dc.subjectMagnetotactic Bacteriaen
dc.subjectGold Nanoclustersrodsen
dc.subjectMolecular Beacon DNAen
dc.titleNovel Metal Clusters for Imaging Applicationsen
dc.typeThesisen
dc.contributor.departmentBiological and Environmental Sciences and Engineering (BESE) Divisionen
thesis.degree.grantorKing Abdullah University of Science and Technologyen_GB
dc.contributor.committeememberMerzaban, Jasmeenen
dc.contributor.committeememberPain, Arnaben
thesis.degree.disciplineBioscienceen
thesis.degree.nameMaster of Scienceen
dc.person.id123812en
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