• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1
  • Tagged with
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Development of novel hypervalent iodine conjugation strategies towards pneumococcal conjugate vaccines

Fumbatha, Sinethemba January 2013 (has links)
Masters of Science / Invasive pneumococcal disease (IPD), which includes potentially fatal conditions such as meningitis, septicaemia and pneumonia poses a threat in children aged <5 years, pneumonia being the leading cause of child mortality worldwide. Even though capsular polysaccharides are the main antigens involved in the immunity to encapsulated bacteria, it was found that in children in that age group, the immune system was unresponsive. Conjugate vaccines however induce immunologic memory and provide long-term protective immunity. Therefore the aim of this project was to develop novel conjugation strategies towards a pneumococcal conjugate vaccines and focuses mainly on the serotypes that are a burden to the African continent. The chemistry involved in developing a conjugate vaccine is of importance beacuse while some polysaccharides contain chemical grouping which can be conveniently utilized for conjugation, many medically important ones require derivatization before they can be coupled to protein. Derivatization of which can be achieved through various strategies, important to note is through hypervalent iodine oxidants. Two hypervalent iodine reagents, O-Methyl substituted-1-hydroxy-1,2-benziodoxol-3(1H)-one 1-oxide (Me-IBX)and modified 1-hydroxy-1,2-benziodoxol-3(1H)-one 1-oxide (mIBX)were successfully synthesized in preparation for the use in polysaccharide, polyribitol phosphate, (PRP) oxidation. The polysaccharide to be oxidised was first size reduced by microfluidisation to allow maximum oxidation. However, the extent to which oxidisation was achieved was not enough to conjugate the polysaccharide to the protein of preference, Bovine Serum Albumin, (BSA).

Page generated in 0.0943 seconds