Description 

Made of 3 µm silica particles, Zenix SEC packing is a breakthrough technology for size exclusion chromatography. 

Combination of 3 µm silica particle size and proprietary surface technology enables highest separation efficiency

 and resolution for biological molecules and water soluble polymers. Available pore sizes of Zenix packings are 

100, 150 and 300Å.

Sepax SEC Product Family Comparison Chart

Packing 

Zenix S

EC Technical Specifications

Characteristic

o Particle size of 3 µm

o Selection of pore size: 80, 100, 150 and 300 Å

o Highest separation efficiency and resolution

o High loading capacity

o High stability over low and high concentration salt

o Lot-to-lot reproducibility

o High protein recovery with intact biological activity

o Negligible non-specific interactions

o Ideal for separation and analysis of biological molecules: proteins, nucleic acids, oligonucleotides, 

peptides and virus

o Ideal for separation and analysis of natural polymers, e.g. polysaccharides, synthetic polymers,

 and nanomaterials, e.g. nanoparticles

Conditions   Column: Zenix SEC-300 (3 µm, 7.8×300mm) Mobile phase: 150 mM phosphate buffer, pH 7.0 Flow rate: 1.0 mL/min Temperature: Ambient Detector: UV 214 nm Injection volume: 5 µL Sample: 1. Thyroglobulin (1.0 mg/mL), 670 kD 2. BSA dimer, 132 kD 3. BSA (1.0 mg/mL), 66 kD 4. Ribonuclease A (1.0 mg/mL), 13.7 kD 5. Uracil (0.1 mg/mL), 120 D

Pore size vs. MW exclusion limit

Column Dimension Availability

Available Zenix SEC column dimensions are 0.75, 1.0, 2.1, 3.0, 4.6, 7.8, 10, 21.2 and 30 mm I.D., and 20, 30, 50, 100, 150, 250, 300 and 600 mm length. Sepax also offers custom-made columns. Both stainless steel and PEEK tubes are available.

High Separation Efficiency

The advantages of developing small particle size are higher efficiency and higher resolution. When particle size is decreased to 3 µm from 5 µm, the column efficiency is almost doubled. As shown in Table 1, the plate numbers of BSA dimmer, BSA, ribonuclease A increased from 2720 to 4600, 6590 to 13090, 11160 to 22000 when the particle size decreased from 5 µm to 3 µm. Fig. 2 and Fig. 3 further show that high efficiency has been achieved by 3 µm Zenix columns with various proteins. The efficiency of p-aminobenzoic acid reached to the plate number of 40,000 for 30 cm long Zenix column.

Figure 1. Separation of protein mixture A by Zenix SEC-300 and SRT SEC-300 columns. 

Conditions   Column: Zenix SEC-300 and SRT SEC-300 Mobile phase: 150 mM phosphate buffer, pH 7.0 Flow rate: 1.0 mL/min for 7.8×300mm, 0.35 mL/min for 4.6×300mm Temperature: Ambient Detector: UV 214 nm Injection volume: 10 µL for 7.8×300mm, 3 µL for 4.6×300mm Sample: 1. Thyroglobulin (1.0 mg/mL), 670 kD 2. BSA dimer, 132 kD 3. BSA (1.0 mg/mL), 66 kD 4. Ribonuclease A (1.0 mg/mL), 13.7 kD 5. Uracil (0.1 mg/mL), 120 D

Table 1. Efficiency of Zenix SEC-300 and SRT SEC-300 columns. 
 

Figure 2. Separation of protein mixture B by Zenix SEC-150 and 300 columns with 7.8 mm ID. 
 

Conditions   Column: 3 µm, 7.8×300mm Mobile phase: 150 mM phosphate buffer, pH 7.0 Flow rate: 1.0 mL/min Temperature: Ambient Detector: UV 214 nm Injection volume: 10 µL Sample: 1. Thyroglobulin, 670 kD 2. γ-Globulin, 158 kD 3. Ovalbumin, 44 kD 4. Ribonuclease A, 13.7 kD 5. p-Aminobenzoic acid, 137 D

Table 2. Efficiency of 7.8×300 mm Zenix SEC-150 and 300 columns. 
 

Figure 3. Separation of protein mixture B by Zenix SEC-150 and 300 columns with 4.6 mm ID. 
 

Conditions   Column: 3 µm, 4.6×300mm Mobile phase: 150 mM phosphate buffer, pH 7.0 Flow rate: 0.35 mL/min Temperature: Ambient Detector: UV 214 nm Injection volume: 5 µL Sample: 1. Thyroglobulin, 670 kD 2. γ-Globulin, 158 kD 3. Ovalbumin, 44 kD 4. Ribonuclease A, 13.7 kD 5. p-Aminobenzoic acid, 137 D

Table 3. Efficiency of 4.6×300 mm Zenix SEC-150 and 300 columns. 
 

High Loading Capacity

Loading capacity is critical for size exclusion separation and purification. Figure 4 shows high loading capacity for BSA as one example (>500 µg for an analytical column). 
Figure 4. BSA loading test on a Zenix SEC-150 column. 

Conditions   Column: Zenix SEC-150 (3 µm, 7.8×300 mm) Mobile phase: 150 mM phosphate buffer, pH 7.0 Flow rate: 1.0 mL/min Temperature: Ambient Detector: UV 214 nm Injection volume: 10 µL

Figure 5. BSA loading test on a Zenix SEC-300 column. 
 

Conditions   Column: Zenix SEC-300 (3 µm, 7.8×300 mm) Mobile phase: 150 mM phosphate buffer, pH 7.0 Flow rate: 1.0 mL/min Temperature: Ambient Detector: UV 214 nm Injection volume: 10 µL

High Stability

The proprietary stationary phases of Zenix SEC packings utilize densely bonded chemistry on the silica surface, which greatly hinders the diffusion of the molecules that would attack the bond of silica-stationary phase layer, thus enabling high stability over a wide range of pH from 2 to 8.5.

Mobile Phase Compatibility

Zenix SEC phases are compatible with most aqueous buffers, such as ammonium acetate, phosphate, trizma and so on. Zenix SEC phases can tolerate high concentration of salts, such as 2.0 M. Furthermore, Zenix SEC columns are stable in both organic solvents, such as methanol, ethanol, THF, DMF, DMSO, and so on; as well as the mixture of water and organic solvents.

Lot-to-Lot Reproducibility

The controlled surface chemistry used to synthesize Zenix SEC phases makes the surface coating highly reproducible, leading to consistent column manufacturing. Separation variation from batch to batch is controlled to be within 5% for retention time.

High Protein Recovery

Zenix SEC phases are hydrophilic and neutral. Proteins and other biological molecules have negligible nonspecific interactions with Zenix stationary phases. The protein adsorption to the silica surface is suppressed, leading to high recovery of intact proteins, maintaining the protein activity after separation. More than 95% recovery is achieved for BSA and lysozyme, the representatives for acidic and basic proteins, respectively.