General Information on Analysis of Saccharides and Organic Acids

Saccharides

Aqueous SEC (GFC) columns are mainly used for the analysis of saccharides such as starch. However, for the analysis of saccharides in the low molecular weight range with molecular weights similar to each other, GFC mode alone cannot provide satisfactory separation. Shodex columns for saccharides analysis have ligand exchange, ion exchange, ion exclusion, reversed/normal phase and GFC mode combined; these columns are suitable for the analysis of various types of saccharides.

For high-selective analysis of organic acids, affinity chromatography columns, AFpak series columns are recommended.

Sample Category Columns to be Selected (SUGAR series)
Saccharides contained in ordinary foods SC1011
Foods containing oligo-saccharides SC1821KS-802, KS-802 + SC1011
Dairy products(Sucrose, Lactose, Lactose, Lactulose) SP0810
Saccharides, organic acids and alcohols in fermented products SH1011, 1821
Sample containing saccharic acids such as uronic and aldonic SH1011, 1821
Saccharides in wood and pulp SP0810

Retention volume ranges of Shodex SUGAR series columns, KS-801SC1011SP0810SC1211 and SZ5532 are shown in this figure.

The column selection according to monosaccharides, disaccharides, oligosaccharides, polysaccharides, sugar alcohols, organic acids and dietary fibers is shown in this figure.

The column selection according to the analytical conditions to be used is shown in this figure.

The column selection according to the combination of saccharides is shown in this table.

Saccharides to be separated Columns to be selected
Monosaccharides
Glu,Fru SP0810,SC1011,SC1211,KS-801
Glc,Gal,Fru SP0810,SC1011,SC1211
Glc,Gal,Man SP0810
Glc,Gal,Ara SP0810,SC1011,SZ5532
Glc,Xyl,Ara SP0810,SC1011,SZ5532
Glc,Fru,Sorbitol SC1011,SC1211,SC1811,SZ5532
Glc,Gal,Sorbitol,Ducitol SP0810,SC1011
Glc,Gal,Man,Sorbitol,Ducitol,Mannitol SP0810
Glc,Fru,Gly,EtOH SC1011,SC1211,KS-801
Glc,Fru+alcohols SC1011,SH1011,SC1211
Glc,Fru+organic acids SH1011,SH1821
Disaccharides
Suc,Lac SZ5532
Suc,Mal SZ5532
Suc,Mal,Lac SZ5532
Mal,Isomaltose SZ5532
Lac,Lactulose SP0810,SC1011
Suc,Glc,Fru SC1011,SC1211,KS-801,SZ5532
Suc,Lac,Glc,Gal,Fru SZ5532
Mal,Glc,Fru,Gly,EtOH SC1011,SC1211,KS-801
Cel,Glc,Gal,Man,Xyl,Ara SP0810
Mal,Glc,Fru,Sorbitol SP0810,SC1011,SC1211,SZ5532
Mal,Glc,Fru+alcohols SC1011,SC1211,SH1011
Mal,Glc,Fru+organic acids SH1011,SH1821
Suc,Glc,Fru,Sorbitol SP0810,SC1011,SC1211,SC1821
Mal,Maltitol SP0810,SC1011,SC1211,SZ5532
Suc,Lac,Mal,Maltitol SZ5532
Glc,Suc,Erythrytol SP0810,SC1011,KS-801
Mal,Glc,Fru,Erythrytol SP0810,SC1011
Oligosaccharides
Sta,Raf,Mal,Glc,Gal,Ara SC1011,KS-801,SZ5532
G4,G3,Mal,Glc SC1011,KS-801,KS-802
Sta,Raf,Suc,Glc SC1011,KS-801,SZ5532
Raf,Suc,Glc,Fru,Ara KS-801
Maltooligosaccharide SC1821,KS-802,SZ5532
Maltooligosaccharide+alcohols SC1821,KS-802,SH1821
Maltooligosaccharide+organic acids SH1821
Maltooligosaccharide+sugar alcohols SC1821,SC1011+KS-802
Sugar alcohols
Xylitol,Sorbitol SC1011,SC1211,SZ5532
Sobitol,Mannitol,Xylitol SP0810,SC1211,SZ5532
Sobitol,Dulcitol,Xylitol SP0810,SC1011,SZ5532
Maltitol,Sorbitol SC1011,SC1211,SZ5532
Maltitol,Dulcitol,Arabitol,Xylitol,Mannitol,Sorbitol SC1211

Ara: Arabinose, Cel: Cellbiose, Fru: Fructose, G3: Maltotriose, G4: Maltotetraose, Gal: Galactose, Glc: Glucose, Gly: Glycerol, Lac: Lactose,
Mal: Maltose, Man: Mannose, Raf: Raffinose, Sta: Stachyose, Suc: Sucrose, Xyl: Xylose

Shodex SUGAR series allow the separation of monosaccharides and disaccharides using aqueous eluent under ligand exchange and GFC modes. Basically, saccharides are eluted in order of decreasing molecular weight by GFC mode. The series provides base line stability and linearity over a wide range when quantifying samples, thus permitting the detection of refractive indexes with high sensitivity.

Ligand exchange mode is a separation mode, which employs ion interaction between metal ions (M+) which are the counter ions of the packing material, and hydroxyl (OH) groups of the saccharides. Saccharides take chair form structure which is energetically stable. Hydroxyl groups are bonded with carbon molecules of chair form and there are two bond types, one is axial(Ax) and another is equatorial(Eq). In the figure above, two cases are illustrated.
(a) Triplet: Three hydroxyl groups having Ax-Eq-Ax structure form a complex with the counter ion. In this case, saccharides are strongly retained by the counter ion.
(b) Pair: Two hydroxyl groups having Ax-Eq structure form a complex with the counter ion. In this case, saccharides are rather strongly reteined by the counter ion but not so strongly as the case of triplet.
In the table below, the numbers of pair and triplet in monosaccharides are shown.

Depending on not only the structure of saccharides but also the type of counter ion, the intensity of interactions applied to the saccharides varies. And, the order of intensity is as follows:

Ag+ < Li+ < Na+ < Zn2+ < Ca2+ < Ba2+ < Pb2+
SUGAR SP0810 (Pb2+) is effective in separating monosaccharides from each other as it is a column in which ligand exchange mode functions most strongly. SUGAR SP0810 (Pb2+) and SUGAR SC1011 (Ca2+), which have divalent metal ions attached to the packing material, can separate saccharides from sugar alcohol as these columns retain sugar alcohol strongly.

The counter-ion of SUGAR KS-801 packing material is Na+. This column elutes saccharides basically in order of decreasing molecular weights as GFC is the dominant mode of this column. However, the column also can separate monosaccharides from each other to some extent as ligand exchange mode contributes to the separation.

In case of Shodex SUGAR columns, GFC mode, ligand exchange mode and adsorption & partition mode are combined in balance to enable good separation of saccharides.

Organic Acids

RSpak KC-811 is suitable for the analysis of organic acids. KC-811 is packed with strong cation exchange gel (bonded with sulfo groups with coordinated H+ as counter ion) where ion exclusion and reversed phase modes function to separate a variety of organic acids. If it is desirable that reversed phase contribute more to the separation, a reversed phase column RSpak DE-613 or DE-413 can be connected to KC-811. RSpak NN-814 is suitable for the separation of aromatic organic acids under ion exclusion and reversed phase modes.