These reversed-phase columns contain Waters innovative embedded polar group technology that “shields” the silica’ residual silanol surface from highly basic analytes. The reduced silanol activity for the SymmetryShield RP18 column significantly improves peak shape and resolution.
Chemistry |
C18 |
Separation Mode |
Reversed Phase |
Particle Substrate |
Silica |
pH Range Min |
2 pH |
pH Range Max |
8 pH |
Maximum Pressure |
6000 psi (415 Bar) |
Endcapped |
Yes |
Bonding Technology |
Shield RP18 |
Silanol Activity |
Low |
Particle Shape |
Spherical |
Particle Size |
3.5 µm |
Endfitting Type |
Waters |
Pore Size |
100 Å |
Format |
Column |
Surface Area |
335 |
System |
HPLC |
USP Classification |
L1 |
Inner Diameter |
4.6 mm |
Length |
150 mm |
Carbon Load |
17 % |
UNSPSC |
41115709 |
Brand |
Symmetry |
Product Type |
Columns |
Units per Package |
1 pk |
Symmetry Shield RP18 Column, 100Å, 3.5 µm, 4.6 mm X 150 mm, 1/pk
With Waters’ patented embedded polar group technology, Symmetry Shield RP18 Columns have been able to set the industry standard of performance for peak shape of basic compounds. The reversed-phased column works as embedded polar group technology “shields” the silica’s residual surface silanols from highly basic analytes. As the embedded polar group is in close proximity to the silica surface, the activity of surface silanols is further reduced within SymmetryShield packing materials. This leads to improvements in peak shape and resolution across a wide pH range and less retention of basic compounds when compared with convention C18 and C8 columns.
SymmetryShield RP18 and Symmetry Shield RP8 Column, 100Å, 3.5 µm, 3 mm X 100 mm, 1/pk deliver USP Tailing Factors of less than 1.2 across a pH range of pH 2 to pH 8. With low limits of detection and quantitation, these columns will enable chromatographers to develop new methods faster while improving productivity. The Shield Technology used in these columns is the ideal lab equipment for applications that require low organic, highly aqueous mobile phase conditions. The reversed-phase particles are water-wettable, allowing for improved interaction between the particles and samples. This leads to stable retention in highly aqueous mobile phases with excellent peak shape.
Like all of the Symmetry family of columns, SymmetryShield RP18 Columns are designed for reproducibility across HPLC applications, allowing for the same chromatographic results across the lifetime of a column or product. As a result of Waters’ commitment to the tightest specifications in the HPLC column industry, Symmetry columns offer excellent reproducibility and reliable results. Engineered using high purity raw materials and tightly controlled processes, SymmetrySheild columns provide the best and most reproducible HPLC columns available.
What Is The Recommended pH Range For Symmetry Columns?
For Symmetry columns, the recommended operating pH range is 2 to 8. The column lifetime will vary depending upon the operating temperature as well as the type and concentration of buffer used. For example, using a phosphate buffer at pH 8 combined with elevated temperatures may lead to a shorter column lifetime.
What Is The Recommended Pressure For Symmetry Columns?
Symmetry columns are designed to tolerate up to 6,000 psi (400 bar) of pressure. However, anything greater than 4,000 – 5,000 psi should be avoided if possible for maximum column and system lifetime.