Water-Soluble, Deep-Red Fluorescent Squaraine Rotaxanes

Doctoral Dissertation


Squaraine dyes are bright deep-red fluorescent molecules that have a donor-acceptor-donor structure resulting in an electron deficient aromatic core that is susceptible to nucleophilic attack. Encapsulation of the dye inside a tetralactam macrocycle forms a squaraine rotaxane which protects the core from nucleophiles and also prevents fluorescence quenching by self-aggregation. This dissertation focuses on the development, syntheses, and application of water-soluble squaraine rotaxanes. The chemical and photochemical stability of water-soluble squaraine rotaxanes with four large stopper groups attached to the dye core was found to be vastly superior to that of squaraine rotaxanes with three and two large stopper groups. Squaraine rotaxanes were functionalized with ionic groups and utilized as non-targeted tracers for in vivo imaging studies, including monitoring disruption of the blood-brain-barrier. A variety of squaraine rotaxanes with potential targeting ability were prepared and tested for application in cell death imaging, cationic cell entry, and bio-conjugation. Bone targeted squaraine rotaxanes with non-bisphosphonate groups were found to be excellent in vivo imaging agents and their bone targeting ability was comparable to that of traditional bisphosphonate probes.


Attribute NameValues
  • etd-03042013-130234

Author Erin Lee Cole
Advisor Bradley D. Smith
Contributor Xavier Creary, Committee Member
Contributor Marvin J. Miller, Committee Member
Contributor Bradley D. Smith, Committee Chair
Contributor Marya Lieberman, Committee Member
Degree Level Doctoral Dissertation
Degree Discipline Chemistry and Biochemistry
Degree Name PhD
Defense Date
  • 2013-02-26

Submission Date 2013-03-04
  • United States of America

  • Rotaxane

  • Cationic

  • Squaraine

  • Bone

  • Squaraine Rotaxane

  • Imaging

  • University of Notre Dame

  • English

Record Visibility and Access Public
Content License
  • All rights reserved

Departments and Units


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