TABLE OF CONTENTS - BGB Analytik AG

LC and LC/MS
Agilent ZORBAX Silica
Agilent ZORBAX Silica
ZORBAX Silica Manufacturing Process – the Making of a Rugged,
High-Purity Silica
584 www.agilent.com/chem/supplies
All Agilent ZORBAX columns are built from porous silica microspheres (PSM) based on silica
sols. The silica particle is made of tiny, solid sol microparticles agglutinated in a patented
polymerization process, then fused together at very high temperatures to form the final
particle (Figure 1). These strong, durable silica particles are called ZORBAX Rx-SIL or ZORBAX
SIL and are the base silicas for ZORBAX columns.
The ZORBAX Rx-SIL process produces ultra-pure (99.995%) particles, with very low metal
content. The final silica particle is fully hydroxylated and of low acidity. The Rx-SIL process also
allows careful and reproducible control of pore size and particle size. These key features – purity
(low acidity), strength, and careful control of pore and particle size – are critical to excellent
chromatographic results and are the building blocks of superior ZORBAX bonded phases.
The table below compares the process used to make the ZORBAX Rx-SIL particles to a second
process – the Xerogel process – commonly used to make silica particles for HPLC columns. To
produce silica with the key features that maximizes chromatographic performance – purity,
strength, controlled pore and particle size, plus higher pH resistance – the Agilent ZORBAX
process is an excellent choice.
SilicaSol
+
Urea (pH~2)
+
CH 2O
O2
Figure 1. Formation of ZORBAX porous silica particles
80Å or 300Å pore
1.8
3.5 μm
5, 7
Eclipse Plus
Eclipse XDB
StableBond SB, 300SB
Bonus-RP
Extend-C18, 300Extend-C18