Rtx-65

Rtx-65 column

Restek Rtx-65 GC Columns

Restek Rtx-65 GC columns feature a highly polar stationary phase composed of 65% diphenyl and 35% dimethylpolysiloxane, engineered to provide enhanced separation of aromatic, polarizable, and structurally similar compounds. This high phenyl content makes the Rtx-65 one of the most selective phases available for separating complex mixtures where subtle polarity differences and pi–pi interactions strongly influence retention.

Rtx-65 columns excel in the analysis of phenols, aromatic amines, nitroaromatic compounds, substituted benzenes, fatty acid methyl esters (FAMEs), flavor and fragrance components, and other semi-volatile analytes requiring strong aromatic interaction for proper resolution. The phase’s tailored polarity enables improved separation of isomeric and co-eluting species that present challenges on lower-phenyl phases such as Rtx-35 or Rtx-50.

With low bleed, strong thermal stability, and Restek’s high-quality deactivation, Rtx-65 supports both GC and GC-MS workflows. Its inertness ensures sharp, symmetrical peaks for reactive or polar compounds while maintaining long-term reproducibility—making it an excellent choice for environmental, chemical, petrochemical, flavor, fragrance, pharmaceutical, and specialty materials analysis.

As an authorized Restek distributor, Chrom Tech supplies Rtx-65 columns in multiple dimensions to optimize resolution and throughput in high-selectivity workflows involving complex aromatic and polar analytes.

Key Definitions
65% Diphenyl Polysiloxane Phase
A high-polarity stationary phase offering enhanced aromatic and dipolar selectivity for isomeric, polarizable, and structurally similar compounds.
π–π Interaction Selectivity
Retention driven by interactions between aromatic rings in the stationary phase and aromatic analytes, enhancing separation of benzene derivatives, PAHs, and substituted aromatics.
High-Polarity Selectivity
Strong retention for polarizable and functionalized organics, improving resolution of phenols, alcohols, nitro compounds, aromatic amines, and other semi-volatile analytes.
Isomeric Resolution
The high phenyl content supports fine resolution of structural and positional isomers that frequently co-elute on lower-phenyl phases.
Low-Bleed MS Compatibility
Rtx-65 is engineered for low bleed at high temperatures, ensuring cleaner baselines and enhanced sensitivity in GC-MS applications.
Frequently Asked Questions
What types of samples benefit most from Rtx-65 columns?
Complex aromatic mixtures, polarizable semi-volatiles, phenols, aromatic amines, nitro aromatics, flavor compounds, and isomeric species requiring strong phenyl selectivity.
How does Rtx-65 differ from Rtx-50 and Rtx-35?
Rtx-65 offers significantly higher phenyl content, providing greater aromatic interaction and stronger selectivity for isomeric and polarizable compounds compared to Rtx-50 (moderate polarity) or Rtx-35 (lower polarity).
Is Rtx-65 suitable for GC-MS workflows?
Yes. Its low bleed and strong thermal stability make it an excellent fit for GC-MS, especially for complex aromatic compounds requiring high-resolution separations.
Does Rtx-65 support high-temperature programming?
Yes. The column provides high thermal stability suitable for eluting heavier semi-volatiles without excessive bleed or performance degradation.