HPLC FAQ´s 

What does Exmere Ltd specialize in?

Exmere Ltd specializes in high-quality silica bulk materials and HPLC solutions. We supply silica from 1.5 µm to 20 µm for HPLC and UHPLC applications and offer a full OEM service for HPLC columns, from media to finished products.

Who are your typical customers?

Our customers include HPLC column manufacturers, OEM partners, distributors, and laboratories worldwide. Many of them sell under their own brand—Exmere works reliably in the background.

Do you offer silica bulk material only, or finished HPLC columns as well?

Both.
We supply silica bulk for customers who pack themselves, and we also provide fully packed HPLC columns as part of our OEM service.

What particle sizes and applications do you cover?

We offer silica bulk materials from 1.5 µm to 20 µm, suitable for HPLC and UHPLC applications, including analytical, preparative, and custom use cases.

Do you support OEM and private-label projects?

Yes—this is one of our core strengths.
We offer OEM and private-label services, including media supply, column packing, specification matching, and scalable production for long-term partnerships.

How fast are your delivery times?

Speed is part of our DNA.
Thanks to stock availability and efficient logistics, we are known for short lead times and reliable delivery, even for recurring OEM orders.

How do you ensure consistent quality?

All materials and products are produced under strict quality standards with batch consistency, traceability, and performance checks. Long-term customers value us for reproducibility, not just specifications.

Can you match or replace existing silica or columns?

In many cases, yes.
We regularly support customers with equivalent or alternative solutions to existing silica materials or HPLC columns. Technical details help us move faster.

Is Exmere suitable for long-term supply agreements?

Absolutely.
Many of our partnerships are long-term OEM collaborations with stable pricing, predictable quality, and reliable availability.

How can I request a quote or start a project?

Simply contact us via the website or email us directly.
For fast processing, please include particle size, pore size (if known), quantity, and application.

What is a C8 and C18 column?

C8 and C18 columns are reversed-phase HPLC columns that differ by the length of the hydrophobic chains bonded to the silica surface.
C18 columns provide stronger retention and are the standard choice for most analytical HPLC applications.
C8 columns offer lower retention, faster run times, and are ideal for very hydrophobic or large molecules.
Exmere supplies C8 and C18 silica bulk and OEM-packed columns across 1.5–20 µm, optimized for UHPLC, HPLC, and preparative use.

Is C8 or C18 more polar?

C8 is more polar than C18.
Because C18 has longer hydrophobic chains, it is less polar and retains non-polar compounds more strongly, while C8 provides weaker hydrophobic interaction and faster elution.

What is C18 used for?

A C18 column is used for reversed-phase HPLC separations of non-polar to moderately polar compounds.
It is the most common choice for pharmaceutical analysis, bioanalysis, environmental testing, and routine QC, offering strong retention and robust, reproducible separations.

How do you use an HPLC column?

An HPLC column is used by first conditioning and equilibrating it with the selected mobile phase, then injecting the sample and running the method at the defined flow rate, temperature, and pressure limits.
Compounds are separated inside the column based on their interaction with the stationary phase and are detected as they elute.
After analysis, the column should be flushed, cleaned, and stored in a suitable solvent to maintain performance and lifetime.

What are the different types of HPLC columns?

Exmere offers a broad HPLC portfolio based on Exsil® silica phases.
This includes Exsil® C18 and Exsil® C8 for reversed-phase separations, Exsil® Pure (bare silica) for normal-phase chromatography, Exsil® IEX phases for ion-exchange applications, Exsil® SEC for size-exclusion chromatography, and Exsil® Chiral phases for enantiomer separations.
All phases are available via www.exmere.eu as silica bulk or OEM-packed columns in particle sizes from 1.5–20 µm for UHPLC, HPLC, and preparative use.

How do you flush a C18, C8 or C4 column?

A C18 column is flushed by first running a high-organic solvent (typically acetonitrile or methanol) to remove strongly retained compounds.
Afterwards, the column can be equilibrated back to the starting mobile phase or flushed with 100% organic solvent for storage.
Always stay within the column’s pressure, pH, and solvent compatibility limits to protect the bonded phase and silica.

What is an ODS and BDS column?

An ODS column (Octadecylsilane) is a standard C18 reversed-phase column with C18 chains bonded to silica, offering strong hydrophobic retention.
A BDS column (Base-Deactivated Silica) is a C18 phase where residual silanol activity is minimized, resulting in improved peak shape for basic compounds.