Size exclusion chromatography (SEC) is frequently applied in industries and many labs for Mw and Mw distribution (MwD) determination because of its time and cost efficiency. Since the retention volume of SEC depends on the hydrodynamic volume rather than Mw, the use of globular coil-type standards Pulluan(P)-82, leads to a significant overestimation of Mw of many plant and fungal polysaccharides with flexible chain conformation. In this research, we developed Mw standards with linear structure and expanded chain conformation. The standard kits were characterized and compared with the performance of P-82.

 

Materials:

Lentinus edodes  (PLE ), Guar galactomannan (GG ),  CM-cellulose (CMC )

Shodex P-82, PS-OBG-Mw( From Putus Macromolecular company)

 

Methods:

GPC and laser LLS

 

Results:

Figure 1:Characterization of a General Mw Standards Kit produced by Putus, with comparison to Pullulan-82

 

 

Table 1:the Mw of the samples by GPC and LLS

Samples	Mw1	Mw2	Mw3
PLE	707k	1160k	790k
GG	122k	331k	112k
CMC	130k	354k	148k

 

Mw¹ : determined by PS-OBG-GMw

Mw²:determined by Pullulan-82

Mw³: determined by LLS

 

The three polysaccharides in Table 1 were widely accepted to adopt expanded chain conformation in solution. The Mw determined by using Putus standard was demonstrated to be more accurate than by using Pullulan-82, compared to their real Mw measured by LLS. Using P-82 to determine Mw of expanded chain leads to a significant overestimation.