Structurally stable N-t-butylacrylamide hydrogel particles for the capture of peptides.

Hydrogel particles have proven to be powerful tools for the capture and concentration of low abundance, low molecular weight peptides and proteins from complex biofluids, such as plasma. The primary means of recovering and washing the particles following harvesting is through centrifugation, which can be a very time-consuming process depending on harvest conditions. To improve the process of particle recovery, washing, and elution we have developed new particle formulations: incorporating N-t-butylacrylamide (tBA) in the polymer backbone with monomers bearing more acidic functional groups and higher degrees of cross-linking. These particle formulations produce a stable architecture that does not significantly respond to changes in environmental conditions, such as pH and temperature. These two new formulations impart structural stability to the particle, control swelling, and improve pelleting through centrifugation, even at high pH values. These structurally stable microparticles yield improved particle recovery while maintaining the peptide capture properties of the particle.