720402.4

NUCLEOSIL® standard silica phases for HPLC

Features

NUCLEOSIL® is a family of totally porous spherical silicas with a very pure and uniform SiO2 structure

• Wide acceptance as routine packings for very different fields of chromatography
• One of the first spherical silicas used in HPLC
• Developed in the early seventies, it became a world-renowned HPLC packing
• Still found in many analytical and preparative applications
• An absolutely reliable choice in HPLC
• The largest variety of modified HPLC silicas available on the market
   

NUCLEOSIL® 4000-7 PEI  
Silica-based HPLC phase for anion exchange chromatography of proteins and peptides
 
Features
 

•  Base material NUCLEOSIL® silica, particle size 7 µm, pore size 4000 Å polymeric, covalently bonded polyethyleneimine network, weakly basic anion exchanger
• Ion exchange capacity 0.15 mmol/g; protein binding capacity 61 mg BSA/g; pH stability 2–8.5; max. working pressure 250 bar
• Separation principle: reversible adsorption of negatively charged substances to positively charged groups on the exchanger material and their subsequent displacement by either increasing ionic strength or pH changes in the mobile phase
• Eluent in column methanol   
•  High selectivity for numerous proteins: e.g., β-lactoglobulins A and B, two proteins differing in just two amino acids, can be separated in only 10 minutes; biological activity of purified proteins is preserved
• Good binding and desorption kinetics for nucleotides as well