| abstract |
The invention relates to activated Streptococcus pneumoniae serotype 10A, 22F or 33F polysaccharides and processes for their preparation, the process comprising the steps of:(a) reacting an isolated serotype 10A, 22F or 33F capsular polysaccharide with an oxidizing agent; and(b) quenching the oxidation reaction by addition of a quenching agent resulting in an activated Streptococcus pneumoniae serotype 10A, 22F or 33F polysaccharide.Comprised is wherein the oxidizing agent is periodate including sodium metaperiodate.Comprised is wherein the temperature of the reaction in step (a) is maintained between 1 and 10°C.Comprised is where the duration of step (a) is between 1 and 25 hours.Comprised is wherein the quenching agent is selected from vicinal diols, 1,2-aminoalcohols, amino acids, glutathione, sulfite, bisulfate, dithionite, metabisulfite, thiosulfate, phosphites, hypophosphites or phosphorous acid, including glycerol, ethylene glycol, propan-1,2-diol, butan-1,2-diol or butan-2,3-diol.Comprised is wherein the temperature of the reaction in step (b) is maintained between 1 and 10°C. |