Automated peptide-resin deprotection/cleavage by a robotic workstation

Area of Science:

• Organic Chemistry
• Biochemistry
• Automation Engineering

Background:

• Automated peptide synthesis is crucial for efficient drug discovery and development.
• Manual deprotection and cleavage steps involve hazardous reagents and can be time-consuming.
• Existing methods require significant human intervention and exposure to noxious chemicals.

Purpose of the Study:

• To develop and validate a robotic workstation for automated peptide deprotection and cleavage.
• To integrate this workstation with existing peptide synthesis platforms.
• To minimize human contact with hazardous reagents during peptide purification.

Main Methods:

• Construction of a robotic workstation around a Zymark robot arm, integrated with a peptide synthesis workstation.
• Automated deprotection using trifluoroacetic acid (TFA)-labile side-chain protecting groups and cleavage from acid-labile resins.
• Utilizing a TFA/scavenger cocktail compatible with Fmoc chemistry and aqueous-ether continuous extraction for purification.

Main Results:

• The apparatus processes 50-500 mg of peptide resin every 2 hours.
• Crude peptides are obtained in 50%-80% yield, free from residual scavengers.
• The method is applicable to most peptides, excluding highly hydrophobic ones.

Conclusions:

• The robotic workstation successfully automates peptide deprotection and cleavage, enhancing efficiency and safety.
• This automated approach minimizes exposure to hazardous trifluoroacetic acid and scavengers.
• The system provides a reliable method for obtaining high-purity crude peptides.