ADME columns can deliver retention comparable to TFA-based methods while using formic acid mobile phases.
Application: Amino Acid Analysis Without TFA
Challenge
Amino acids are highly polar compounds that are difficult to retain on conventional C18 columns under MS-compatible conditions.
- With formic acid → poor retention
- With TFA → improved retention, but:
- Ion suppression
- Poor MS sensitivity
Approach
Comparison of:
- C18 column with formic acid
- C18 column with TFA
- ADME column with formic acid
Results (THIS is the key insight)
C18 + Formic Acid
- Early elution of polar amino acids
- Insufficient retention
C18 + TFA
- Improved retention
- Comparable separation
- But not MS-friendly
ADME + Formic Acid
- Strong retention of amino acids
- Comparable to C18 + TFA
- Fully compatible with LC-MS
👉 This is the money statement:
Retention comparable to TFA-based methods can be achieved using MS-friendly conditions.
Conclusion
ADME columns enable the analysis of polar compounds such as amino acids using formic acid mobile phases, achieving retention comparable to TFA-based methods while maintaining LC-MS compatibility.
