Development of a biosensor using aptamer/antigen interactions

  • Daniel George Fordham

Student thesis: Doctoral Thesis


The use of aptamers acting within novel biosensors as molecular recognition elements is well documented with a wide variety of techniques being adapted to take advantage of the benefits of oligonucleotide detection. A continuing barrier to the commercial use of ssDNA or RNA aptamers remains the lack of a high-throughput system that confers reliable selection and description of suitable species. Here we describe simple methodologies that utilise fusion proteins, modified affinity chromatography, HPLC, and, nanopore assays, along with other techniques to isolate novel aptamers to well-characterised proteins. These methods have yielded novel aptamers to the HsdR, and HsdS subunits of type I restriction modification system EcoR124I and to the human rhinovirus 3C protease, along with an enriched libraries for nitrotyrosine. In addition to the isolation of novel aptamer species, methods for the characterisation of the binding capabilities of candidate aptamers are presented. The techniques of SPR, EMSA, and dot blotting are evaluated and utilised in the appraisal of the novel aptamer sequences.

Date of Award31 May 2011
Original languageEnglish
Awarding Institution
  • University of Portsmouth
SupervisorJames McClellan (Supervisor)

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