Preparation of abiotic polymer nanoparticles for sequestration and neutralization of a target peptide toxin

Synthetic polymer nanoparticles (NPs) with intrinsic affinity for target biomacromolecules hold great promise in the development of novel tools for biological and biomedical research. We recently reported the design and synthesis of abiotic, synthetic polymer NPs with high intrinsic affinity for a peptide toxin melittin. The NP was selected by screening a small library of NPs (∼100 nm) composed of various ratios of monomers that contain functional groups complementary to the peptide melittin. The selected polymer NP, a co-polymer of acrylic acid (AAc), N-tert-butylacrylamide (TBAm), N-isopropylacrylamide (NIPAm) and N,N'-methylenebisacrylamide (BIS), effectively captures and neutralizes the toxicity of the peptide through a combination of electrostatic and hydrophobic interactions. This protocol describes a step-by-step procedure for the preparation and evaluation of synthetic polymer NPs for sequestration and neutralization of the target peptide toxin. The polymer NPs can be synthesized in a one-step polymerization reaction using commercially available reagents. The polymerization reaction for the synthesis of polymer NPs takes several hours, and the total protocol including subsequent purification and characterization by dynamic light scattering, NMR and toxicity neutralization assays takes 1-2 weeks in total.