Analytical Columns

• BioSphere™ C4 – Optimized for Intact Proteins
  • Particle size=5 µm
  • Pore size=300 Å

Featuring a 300-Å pore size and C4 alkyl ligand, this BioSphere™ stationary phase provides enhanced surface accessibility for large biomolecules. The reduced hydrophobicity of the C4 phase minimizes protein unfolding, while the expanded pore architecture facilitates efficient mass transfer and interaction with intact proteins.
Ideal for Reversed Phase LC-workflows targeting native-state protein isoforms and post-translational variants.

• BioSphere™ C8 – Reliable Retention for Hydrophobic Peptides
  • Particle size=5 µm
  • Pore size=120 Å

This C8 phase is optimized for the separation of hydrophobic peptides, including membrane-associated fragments and highly lipophilic tryptic peptides. The moderate chain length of the BioSphere™ C8 ligand provides sufficient interaction without excessive retention, resulting in sharp peaks and reproducible elution profiles. A chemical modification ensures phase stability in highly aqueous mobile phases, maintaining consistent performance even under low organic conditions.
An ideal choice for Reversed Phase LC of peptides in aqueous buffers or gradients with minimal organic content.

• BioSphere™ C18 –The Gold Standard for Proteomics
  • Particle sizes=1.9 µm, 3 µm and 5 µm
  • Pore size=120 Å

This C18 phase is purpose-built for the analysis of complex peptide mixtures, including whole-proteome digests from biological samples. Its high surface interaction capacity ensures excellent retention and resolution, even for low-abundance peptides in highly complex matrices. BioSphere™ C18 is available in multiple particle sizes (1.9 µm, 3 µm and 5 µm), allowing you to tailor separation efficiency and system compatibility to your specific workflow. A chemical modification ensures stable performance in highly aqueous mobile phases, while the phase maintains exceptional reproducibility under extended, slow-gradient LC conditions.
A robust and versatile choice for in-depth proteomics applications.

• PLRP-S™ –High‑performance PS/DVB media for intact proteins and oligonucleotides
  • Particle sizes=5 µm
  • Pore size=1000 Å

The PLRP‑S™ stationary phase is a wide‑pore polystyrene/divinylbenzene (PS/DVB) material engineered for high‑resolution reversed‑phase chromatography of large biomolecules. Its silica‑free design ensures stable retention, broad pH tolerance (1–14), and excellent thermal robustness, making it ideal for demanding LC and LC‑MS workflows. This pore/particle combination is widely used for intact protein analysis, mAb subunit separations, and long synthetic peptides, including GLP‑1 analogues and other therapeutic biomolecules.
A strong choice for laboratories working with proteins, peptides, and nucleic acids.

• Customer-Supplied Stationary Phase

For specialized applications or proprietary chemistries, Sothis Separations offers the option to fabricate analytical columns using customer-supplied stationary phases. In close consultation, we ensure optimal packing conditions and column geometry to match your analytical goals. Whether you’re working with novel materials, custom surface modifications, or unique selectivity profiles, our fabrication process guarantees high-performance integration into nanoscale LC workflows. This service is ideal for research groups and developers seeking full control over column chemistry while benefiting from our precision engineering and compatibility with the Deans Column Switching System.