calculate the amount of water and sugar to be added, use
the following formulas:
μg sugar ¼ weight μg  purity% Â
no hydrated sugar MW
hydrated sugar MW
(see Note 4)
(If the sugar is not in the hydrated form, the last ratio present in
the formula is equal to 1)
μL water ¼
μg sugar
4:5
l
Weigh an empty 500 mL glass bottle on the technical balance
and transfer 1 mL of the sugar solution prepared in previous
section; then add water up to achieve a total weight of 400 g in
order to obtain a solution with a concentration of 11.25 μg/mL
for GlcNAc.
(c) Thermo Dionex CarboPac PA10 column (4 Â 250 mm) coupled with a PA10 guard column (4 Â 50 mm).
(d) TFA 8 M solution.
l
Under chemical hood, with the glass cylinder, measure
30 mL of TFA and transfer it into the glass bottle.
l
With a pipette, add in the bottle 20.5 mL of water and
gently mix.
(e) TFA 4 M solution.
l
Dilute 10 mL of TFA 8 M adding 10 mL of water.
(f) Eluents.
l
Sodium hydroxide (NaOH) 50 mM.
– Fill the eluent bottle with 2 L of water using the volumetric flask.
– Degas for 15 min by bubbling Helium.
– With a pipette, add 5.2 mL of NaOH 50% (Baker, cod.
7067) to the bottle.
– Degas for 10 min more.
l
NaOH 500 mM.
– Fill the eluent bottle with 2 L of water using the volumetric flask.
– With a pipette, remove 26 mL of water from the bottle.
– Degas for 15 min by bubbling Helium.
– With a pipette, add 26 mL of NaOH 50% to the bottle.
– Degas for 10 min more.
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Francesca Micoli et al.