Low Dead Volume Design

Low dead volume design

Minimal extra-column band broadening is required to take full advantage of the highest efficiency GPC columns The EcoSEC Elite GPC System is engineered to minimize system dead volume. The semi-micro design allows the use of GPC columns with smaller ID (4.6 mm) and shorter lengths (15 cm) such as the TSKgel SuperMultiporeHZ columns. Together with a small stroke volume pump and a 2.5 μL RI flow cell, the EcoSEC Elite GPC System allows accurate and precise molar mass measurements, particularly when benefiting from state-of- the-art column technology.

As shown in Figure 1, when run on the EcoSEC Elite GPC System, the TSKgel SuperMultiporeHZ-N (4.6 mm ID × 15 cm) column achieves separation efficiency equivalent to that of a conventional high speed column (7.8 mm ID × 30 cm), but analysis time is reduced to half that of a conventional column and one-sixth the amount of solvent is consumed.

Figure 1. Comparing semi-micro and conventional GPC columns 

Columns:            A. Conventional columns, 7.8 mm ID × 30 cm × 4
                            B. TSKgel SuperMultiporeHZ-N, 3 µm, 4.6 mm ID × 15 cm × 4
Mobile phase:    THF
Flow rate:           A. 1.0 mL/min
                            B. 0.35 mL/min
Detection:          RI (EcoSEC Elite GPC System)
Temperature:     40 °C
Injection vol.:     A. 50 µL  B. 10 µL
Sample:              poly(teramethylene ether glycol) (PTMEG 650), 10 g/L

The combination of the EcoSEC Elite GPC System and semi-micro columns provides significant solvent related cost savings while doubling sample throughput without compromising resolution. As shown in Table 1, the solvent related cost savings are extraordinary for samples requiring expensive solvents such as hexafluoroisopropanol.

Table 1. Annual solvent cost saving with semi-micro columns and the EcoSEC Elite GPC System


Competitive GPC System

EcoSEC Elite GPC System


Chloroform ($17/L) $1,830 $295 $1,535
DMF* ($25/L) $2,600 $416 $2,184
NMP* ($30/L) $3,082 $493 $2,589
THF* ($40/L) $4,160 $666 $3,494
HFIP* ($1,000/L) $96,493 $15,439 $81,054

*DMF: dimethylformamide; NMP: N-methylpyrrolidone; THF: tetrahyrofuran; HFIP: hexafluoroisopropanol