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Chemically bonded aminopropyl silicas are the most widely
used for the hydrophilic interaction chromatography of
carbohydrates. The mobile phases consisting of acetonitrile-
water mixture are usually employed. All of the commercial
columns used for carbohydrate chromatography are packed with
porous sorbents. In a column packed with porous sorbent, mass
transfer effects due to pore diffusion of solutes into and out
of the sorbent may result in a longer elution time.
However, when non -porous silica sorbents are employed as
packing materials. The solutes can be rapidly separated on the
column.
In this research, the non-porous silica having an average
diameter of 3.04 μm was prepared . The non-porous silica
was silanlized with α-aminopropyltriethoxy silane to
introduce terminal amino groups with a densityof 1.98 μmole/m2
on the surface. It is believed that the modified silicacovered a
monolayer of silane on its surface. The resultant aminopropyl-
silicasthen were packed into two columns (5 cm×0.46 cm I.D. and
10 cm×0.46 cm I.D.). The mixture of glucose and lactose
could be separated in 3 min in the 5-cm long column at a flow
rate of 0.5 ml/min. The maximum loading capacity of this column
was determined to be 5 μg. A sample with a glucose
concentration down to 0.1 mg/l could be quantitatively
analyzed. The results indicated that the column was suitable
for analysis of low sugar concentrations. The lowest value of
plate height could be reached by reducing the flow-rate to
0.35 ml/min .The 10-cm long column was effective for the
separation of fructo-oligosaccharides produced from sucrose
solution catalyzed by β-fructofuranosidase. The separation on
the 10-cm long column was accomplished in 8 min at a flow-rate
of 0.5ml/min . Whereas it took 24 min to conclude the
separation of fructo -oligosaccharides products on the
Supelcosil LC-NH2 column (25 cm×0.46 cm I.D.) with a flow-rate
of 1ml/min. However, due to the low bindingcapacity of the
prepared column, fructose could not be effectively
separatedfrom sucrose.
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