From a chromatographic standpoint, there is no measurable difference in performance between clear and amber RSA™ (Reduced Surface Activity) vials. Both vial types are manufactured using the same proprietary RSA™ process, which eliminates surface silanols and minimizes adsorption of basic analytes—ensuring consistent performance across vial types.

Key Observations from QC and R&D Testing:

• Adsorption behavior: No significant difference in the adsorption of basic compounds between clear and amber RSA™ vials.
• pH stability: No observable variation in pH-related effects on sample diluents.
• Surface chemistry: Both vial types exhibit identical surface activity profiles due to the RSA™ manufacturing process.

When to Choose Amber Glass:

Amber RSA™ vials are recommended for light-sensitive analytes, as the amber coloration provides protection against UV and visible light exposure. This is particularly important for compounds prone to photodegradation.

Glass Composition:

• Clear RSA™ vials are manufactured from Type I, Class A 33 expansion borosilicate glass.
• Amber RSA™ vials are produced using N51A expansion borosilicate glass, which includes iron and other oxides to achieve light-blocking properties.

Conclusion:

The choice between clear and amber RSA™ vials should be based on sample light sensitivity, not chromatographic performance. Both options deliver the same high level of surface inertness, dimensional precision, and LCMS compatibility expected from RSA™ technology.