Most part of our products are polymeric glycoconjugates. Quality control is performed both at the level of initial carbohydrate ligands and at the level of final conjugates.
- Aminoalkyl glycosides are tested using H-NMR and reversed-phase HPLC, only the substances having the purity > 95% are subjected to conjugation.
- The labels either synthesised at home or purchased ones are tested with H-NMR.
- Starting activated polymer was characterised by 13C-NMR, a polymer was obtained in amount about 100 g, all polymeric glycoconjugates are synthesised from the same batch of the initial polymer.
- In order to exclude variations in the label amount, a large amount of an intermediate, containing, for example, 1% of fluorescein, is obtained. ALL carbohydrate derivatives are then synthesised from this intermediate. This approach guarantees the same content of flu label in the conjugate, thus making possible and correct the quantitative comparison of such conjugates, e.g. in flow cytometry.
- Though the attachment of an aminoalkyl glycoside to the activated polymer is performed in 100% yield, the ready conjugates are subjected to quantitative analysis of monosaccharide composition: glycoconjugate is hydrolysed to monosaccharides which are analysed using HPLC.
- ELISA of glycoconjugate is performed in case of availability a specific reagent (antibody, lectin) to the given carbohydrate ligand.
- If a customer wishes to obtain glycoconjugate batches of high consistency during long term, we can reserve a separate batch of the initial activated polymer. This approach guarantees the identity of the products obtained in different time both by the label content and by molecular weight.
- After lyophilyzation almost all PAA-glycoconjugates produce solid, stable during years product. However, some of them, such as those containing phosphate or sulfate can spontaneously convert to oil-like state. The product being coated the vial bottom can be practically invisible. This fact does not indicate the loss of quality: in case of correct storage the oil product is stable for at least one year.
- Glycoconjugates can be infinitely freeze dryed. We recommend to store the incopmletly used product in lyophilised state (in case of the long-term storage) or in frozen aqueous or water-glycerol solution. It is not recommended to store diluted solutions in plastic vial (especially polystyrene) as in this case the loss of the substance due to the gradual adsorption on plastic can take place. It is not possible to use borate buffers.
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