(W1030-05-26) Studying the Effect of Increased Modifier Range on EPSA Analysis by SFC

Purpose: Bioavailability and cell membrane permeability of drug candidates is vital to the success of any potential therapeutic.  The ability to assess these qualities quickly and early in the development process can allow the elimination or promotion of candidates, thereby streamlining the drug development process.  EPSA offers a rapid, SFC-based technique that has been shown to provide good correlation to more time intensive and traditional permeability studies.  Building on the methods found in literature, this study will demonstrate the optimization potential of increased modifier percentage to both reduce the time to result, and allow for additional standards to increase the range of resolvable polarity.

Methods: Based on the work of Goetz and Romero, this study uses the Chirex 3014 stationary phase and methanol as the modifier.  The Shimadzu Nexera UC SFC system was used in a binary gradient configuration, employing linear gradients up to 95% modifier.  Standards used for EPSA mapping were taken from Goetz, et al.

Results: The retention time map and EPSA values were assigned to the polarity standards, and replicates (n=5) obtained.  Peptide samples were then injected with replicate (n=3) to generate EPSA values.

Conclusion: By increasing the available modifier gradient percentage, EPSA studies can expand the log P of standards beyond furosemide (logP = 2.03), and increase the potential throughput of these assays by eluting strongly retained compounds more quickly.  This approach can provide rapid feedback in the drug design phase as a tool to promote candidates with the required permeability to continue development.