Applying Native Chemical Ligation to the Development of Magnetically-responsive Drug Delivery Platforms for Biomedical Applications

  • Raúl Horacio Camarillo López

Student thesis: Phd


The potential of magnetic nanoparticle-vesicle assemblies (MNP-V) as remote controlled drug delivery platforms capable of inducing cellular responses under magnetic stimuli has been previously demonstrated in the Webb group at the University of Manchester. To create these magnetoresponsive nanomaterials biotin-avidin and Cu-histidinyl multivalent recognition were employed. This thesis describes an exploration of the potential of thiol-thioester exchange reactions (leading to native chemical ligation, NCL) to create magnetoresponsive materials, which potentially have applications in biomedicine. Firstly, iron oxide magnetic nanoparticles have been synthesised using a thermal co-precipitation method followed by chemical modification with sulfhydryl motifs for use as smart biomaterials. Knowing that the behaviour and reactivity of nanoparticles is highly influenced by their physicochemical properties, a thourough characterisation of these particles has been obtained. Secondly, during this project, several thioester derivatives have been synthesised that can be incorporated into the membranes of 800 nm liposomes. Among these, the spectrophotometric properties of synthetic lipid 38 allowed the investigation of trans-thioesterification rates with cysteinyl functionalities, both in solution and at the phospholipid membrane interface of liposomes. Product identification has been achieved using mass spectrometry and 1H-NMR spectroscopy. Finally, the conditions required to induce the release of a dye (e.g. 5(6)-CF) from MNP-V upon exposure to an AMF pulse have been established. Aurintricarboxylic acid (ATA), a general inhibitor of nucleases has been investigated as interesting payload due to its fluorescent and anti-viral properties.
Date of Award1 Aug 2017
Original languageEnglish
Awarding Institution
  • The University of Manchester
SupervisorSimon Webb (Supervisor) & Robert Dryfe (Supervisor)


  • Thiol-thioester exchange
  • Nanotechnology
  • Native Chemical Ligation
  • Magnetic Nanoparticles
  • Drug Delivery Systems

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