Frequently Asked Questions About Cogent HPS™
- What is Cogent HPS™?
- What is the pH Stability of Cogent HPS™?
- What is the column to column reproducibility?
- Who is the manufacturer of the silica that is used in Cogent™ HPLC columns?
- How long have Cogent HPS™ HPLC products been on the market?
- Do you have a specific set of limits for metals in the silica? If so, what are they and which metals do you test for?
- Why is Cogent HPS C18 columns so good for separation of peptides?
- What is the biggest difference between Cogent HPS™ columns and most HPLC columns available on the market today?
1. What is Cogent HPS™? [top]
Cogent HPS™ is a state-of-the-art stationary phase (both bonded and non bonded) that is designed for
applications that require high purity silica. Metal content in Cogent HPLS is extremely low and this produces very
good stability and “deactivates” the silica for use with basic analytes. A very smooth and uniform silica surface
results for mechanical strength and stability.
Cogent HPS™ is available for HPLC with unmodified silica, C18, C8, Amino, Cyano or Phenyl stationary phases.
2. What is the pH stability of Cogent HPS™? [top]
These columns are extremely stable in from pH 2.0 to pH 8.6. Depending on the concentration of the acid or base will
determine if these columns would be stable outside of this range.
3. What is the column to column reproducibility? [top]
These columns have been determined to be very reproducible from column to column, from batch to batch by customers
from all parts of the world.
4. Who is the manufacturer of the silica that is used in Cogent™ HPLC columns? [top]
MicroSolv Technology is the sole source and producer of the silica used in HPS™ HPLC Columns. The silica is
manufactured with proprietary sol-gel technology and quality controlled for purity and physical characteristics. The
bonding process is organo-silane with extensive, double end capping.
5. How long has Cogent HPS™ been on the market? [top]
The silica and bonding has been in production and on the market since April 2001.
6. Do you have a specific set of limits for metals in the silica? If so, what are they
and which metals do you test for? [top]
Yes (see details below)
| Metal p.p.m. |
Levels specification |
Found |
| Na |
<10 |
<1 |
| Al |
<10 |
<1 |
| Fe |
<10 |
<1 |
| Ti |
<10 |
<1 |
| K |
<10 |
None detected |
|
7. Why is Cogent HPS C18 columns so good for separation of peptides? [top]
There are two different, but complimentary properties of the bonded phase silica that govern the retention/separation
of peptides and these are:
- low alkali metal and Fe content found in the Cogent HPS™ silica
- unique, proprietary bonding method used in the manufacture of the stationary phase
8. What is the biggest difference between Cogent HPS™ columns and most HPLC columns available on the market today? [top]
The Cogent HPS™ silica has a very narrow particle size range and consequently the column efficiency and durability
of the phase improves significantly. Additionally, the bonded phases have been manufactured under strict anaerobic
conditions and unique bonding techniques have been employed. For this reason the bonded phases are covered uniformly on
the silica surface producing better results in the short and long run.
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