Surface Chemistry and Stability

The primary distinction between RSA-Pro™ and RSA-Pro X™ vials lies in the type of surface treatment applied to the RSA™ glass and the resulting hydrolytic stability of each.

• RSA-Pro™ utilizes a vapor-phase deposition process in which silane-based materials are ionically bonded to the glass surface. This treatment imparts hydrophobicity but is not hydrolytically stable. As a result, RSA-Pro™ vials:

  • Are not suitable for autoclaving or freezing
  • May lose their hydrophobic properties over time, especially in aqueous environments
  • Are available only as custom order items

• RSA-Pro X™, by contrast, employs a proprietary surface modification process that covalently bonds hydrophobic materials directly to the RSA™ glass surface. This results in:

  • Exceptional hydrolytic stability, even with prolonged exposure to water
  • Compatibility with autoclaving, freezing, and freeze-thaw cycles
  • Long-term retention of hydrophobicity—stable for years under standard laboratory conditions

Summary of Key Differences

Recommendation

For applications involving aqueous solutions, long-term storage, or hydrophobic analytes such as proteins, peptides, and enzymes, RSA-Pro X™ is the preferred choice. Its robust surface chemistry ensures consistent performance and minimal analyte loss over time.