The discontinuation of polar resins such as PEGA has created a bottleneck within peptide chemistry and chemical biology.1 We present a novel sustainable and scalable approach producing high quality PEGA reins via inverse suspension polymerization in recyclable silicone oil, avoiding highly restricted solvents like CCl4, and minimizing waste. Bulk synthesis produced the beaded resin at a size range of 200-400 µm and resulted in over 700 mL of water-swelled resin per batch, suitable for more than 500 medium scale peptide syntheses. These beaded resins are spectroscopically transparent, and act as a stealth polymer that do not interact with proteins, biomolecules or cells. Providing the ideal template for protein immobilization technologies. The bead formation was optimized by obtaining precise temperature control and using PEG1500-(O-TBDMS)2 as detergent. Flow synthesis were further refined to ensure uniform bead control, yielding the optimal diameters for on-bead bioassays. The swelling capabilities of the resulting PEGA resin was evaluated through a broad range of green solvents, showing excellent solvent compatibility and confirming its suitability for green solid-phase synthesis technologies.
Performance of the resin was validated through successful peptide assembly of Leu-enkephalin utilizing Fmoc-based protocols. Likewise, the performance as a stealth polymer was demonstrated through development of a simple covalent immobilization technique of green fluorescent protein confirming uniform biomolecule diffusion.2 Further optimization using weaker activation of the resin, has resulted in a novel site specific His-tag acylations at the N-terminus of proteins, while maintaining the biological activity of the protein.
Incorporation of arginine and ATOTA labeled microparticles in the polymer matrix establishes a foundation for efficient optical encoding, offering the option of efficient synthesis and characterization of substrates in combinatorial libraries.3
Our procedures empowers laboratories to maintain an independent and environmentally friendly production of PEGA resin, advancing initiatives in peptide and protein research without compromising on performance.