Lc20 high performance liquid chromatography pump

The molecular weight distributions of the HA and PHA was determined by gel permeation chromatography (GPC, Shimazu LC-20A, Japan). The instrument configuration was as follows: LC20 high-performance liquid chromatography pump (Shimadzu, Japan), RID-20A refractive index detector (Shimadzu, Japan), TSKgel GMPWXL water phase gel chromatography column (TOSOH, Japan), Rheodyne 7725i manual six-port valve sampler (20 µl loop, USA), and HW-2000 GPC chromatography workstation. Polyethylene glycol samples were used as standard substances. HA or PHA (100 mg) was dissolved in 10 mL of a 0.1 M NaOH solution and then filtered through a 0.22 μm membrane filter before determination. The operation parameters were as follows: 35 °C column temperature, 0.1 N NaNO₃ and 0.06% NaN₃ aqueous solution as mobile phase, and 0.6 mL/min flow rate.

The molecular weights of polysaccharides were measured by gel permeation chromatography (GPC) with an LC20 high-performance liquid chromatography pump (Shimadzu, Japan) and an RID-20 refractive index detector (Shimadzu, Japan). The column was eluted with an aqueous solution of sodium nitrate (0.1 M) at a flow rate of 0.5 mL/min. The molecular weight of JCH-a1 was calculated from curves calibrated with T-series dextran standards (MW 642, 334, 49.4, 2.2, 0.63 kDa).