Studies of Multivalent Probes as Bacterial Imaging Fluorophores and Agglutination Agents

Master's Thesis


This study evaluates the performance of Bis-Zinc II dipicolylamine (ZnII-DPA) conjugated squaraine rotaxane as bacterial targeting probes. Firstly, binding assays with planktonic bacteria show this probe to selectively bind cells best during the log phase of the cell cycle, with up to 99% binding efficiency. These probes binds both Gram-negative and Gram-positive strains of bacteria with varying affinity depending on phospholipid content of Gram-positive cells and structural makeup of the Gram-negative cell wall. Planktonic staining assays and flow cytometry of the amide version of the probe show a threefold increase in the fluorescence intensity when compared to
treatments with the triazole version. Phosphatidylserine Sensor 480 analogs with one ZnII-DPA unit exhibit a similar affinity to the bacterial cells, and a faster diffusion rate. Multivalent squaraine rotaxanes exhibit a high affinity for a wide range of bacteria at low concentrations with planktonic bacterial staining assays and slide agglutination assays. Selectivity to the bacteria and cross linking was observed even when treating bacteria in the presence of mammalian cells. Bis-ZnII DPA versions of the probe were more effective as agglutination agents than the mono-ZnII DPA version.


Attribute NameValues
  • etd-12132009-223918

Author Lica Abu-Esba
Advisor Dr. Bradley Smith
Contributor Dr. Patricia Clark, Committee Member
Contributor Dr. Bradley Smith , Committee Chair
Contributor Dr. Jeffrey S Schorey , Committee Member
Contributor Dr. Shahriar Mobashery , Committee Member
Degree Level Master's Thesis
Degree Discipline Chemistry and Biochemistry
Degree Name MS
Defense Date
  • 2009-12-01

Submission Date 2009-12-13
  • United States of America

  • Squaraine Rotaxane

  • Multivalent probes

  • bacterial imaging agents

  • bacterial fluorophores

  • Agglutination agents

  • University of Notre Dame

  • English

Record Visibility Public
Content License
  • All rights reserved

Departments and Units


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