ApartSIL C18 HPH is a specialized high-performance liquid chromatography (HPLC)
column designed to handle demanding analytical tasks, particularly in high-pH environments.
This column is tailored for applications requiring robust separation of non-polar to
moderately polar compounds while maintaining stability under harsh conditions. Below is a
detailed overview of ApartSIL C18 HPH:
1. Structure and Composition
C18 Bonded Phase: The ApartSIL C18 HPH column features an 18-carbon long
hydrocarbon chain (octadecyl) chemically bonded to the silica particles. This C18
chain provides the column with its hydrophobic characteristics, making it suitable for
reverse-phase chromatography.
High-pH Stability: ApartSIL C18 HPH is specifically designed to withstand high-pH
conditions, typically up to pH 10-12. This is achieved through special bonding
chemistry and the use of highly stable silica, making the column resistant to
degradation under alkaline conditions.
Silica Support: The silica particles used in ApartSIL C18 HPH are often highly pure
and spherical, providing a large surface area for interaction and ensuring high
efficiency and resolution in separations.
2. Applications
Pharmaceutical Analysis: Widely used in the separation and analysis of
pharmaceutical compounds, particularly those that require alkaline mobile phases for
optimal separation.
Basic Compound Analysis: Ideal for the separation of basic compounds, which often
require high-pH mobile phases to avoid tailing and ensure good peak shape.
Peptide and Protein Separation: Suitable for the separation of peptides and small
proteins, especially when alkaline conditions are necessary to prevent adsorption or
degradation.
Environmental Analysis: Effective for analyzing pollutants and contaminants in
environmental samples that require high-pH conditions for optimal separation.
Food and Beverage Testing: Used to detect and quantify various compounds in food
and beverages, particularly those that are sensitive to acidic conditions.
3. Key Features
High-pH Stability: The primary feature of ApartSIL C18 HPH is its stability in high-
pH environments, allowing for the use of alkaline mobile phases without degrading
the silica support or bonded phase.
Extended Column Life: The robust bonding chemistry and stable silica matrix
contribute to a longer column lifespan, even under harsh analytical conditions.
Wide pH Range: ApartSIL C18 HPH can operate across a broad pH range, typically
from pH 2 to 12, providing flexibility in method development.
Temperature Tolerance: The column is generally stable at elevated temperatures,
often up to 80°C or higher, which can enhance separation efficiency and reduce
analysis time.
Versatile Applications: Suitable for a wide range of applications, particularly those
requiring high-pH mobile phases, without compromising column performance.
4. Operating Conditions
Mobile Phases: ApartSIL C18 HPH is compatible with a variety of mobile phases,
including those with high pH, such as ammonium bicarbonate or sodium phosphate
buffers. It also performs well with standard organic solvents like methanol and
acetonitrile.
Flow Rate: The column typically operates efficiently at flow rates ranging from 0.5 to
2.0 mL/min, depending on the specific application and column dimensions.
Column Dimensions: Available in various sizes, commonly with diameters of 2.1
mm to 4.6 mm and lengths from 50 mm to 250 mm, allowing for flexibility based on
the analytical needs.
5. Maintenance and Care
Column Conditioning: Proper conditioning with the intended mobile phase,
particularly at the desired pH, is essential before use to ensure stable and reproducible
performance.
Storage: The column should be stored in a solvent mixture compatible with the
stationary phase and pH range, typically a neutral pH buffer or a mixture of water and
organic solvent.
Preventing Contamination: Regular filtration of samples and mobile phases is
recommended to avoid particulate contamination, which can reduce column efficiency
and lifespan.
6. Limitations
Solvent Compatibility: While ApartSIL C18 HPH is robust under high-pH
conditions, care must still be taken with certain solvents, particularly strong acids or
bases that could exceed the column's stability range.
Silica-Based Constraints: Despite its enhanced stability, the silica support can still
degrade under extreme conditions (e.g., very high pH for extended periods), so
monitoring and optimizing conditions are essential.
7. Comparison with Standard C18 Columns
High-pH Tolerance: ApartSIL C18 HPH offers superior stability in high-pH
environments compared to standard C18 columns, which typically degrade at pH
levels above 8.
Basic Compound Separation: The column provides better peak shape and retention
for basic compounds, which might suffer from tailing or poor resolution on standard
C18 columns under neutral or acidic conditions.
Longer Lifespan: Due to its enhanced stability, ApartSIL C18 HPH generally offers
a longer operational life in demanding applications compared to standard C18
columns.
8. Alternatives
C18 Columns: For applications that do not require high-pH conditions, standard C18
columns may suffice and could be more cost-effective.
Polymeric Columns: For extreme pH conditions (both high and low), polymeric
columns may offer even greater stability, though they may lack the selectivity of
silica-based columns.
C8 Columns: If less retention and faster separations are desired, a C8 (octyl) column
may be an alternative, though it might not perform as well in high-pH environments.
ApartSIL C18 HPH is a highly specialized HPLC column that excels in high-pH
environments, making it an ideal choice for analysts working with basic compounds,
peptides, and other challenging analytes. Its enhanced stability and versatility make it a
valuable tool in various industries, including pharmaceuticals, environmental testing, and
food and beverage analysis.