Instead of using liquids or tiny droplets for combinatorial peptide microarray synthesis, PEPperPRINT utilizes solid amino acid microparticles with embedded and pre-activated amino acids. Melting of these particles simply releases the immobilized amino acids to initiate coupling on the microarray support. The oily consistency of the liquefied material finally enables the high-density synthesis of peptide microarrays and thereby circumvents the drawbacks arising with conventional printing and spotting techniques. The microarray quality is corrupted neither by evaporation of solvent, clogging of printing mechanics, nor by blurred or inhomogeneous spots. Due to the long-term stability of the amino acid microparticles, a further advantage of PEPperPRINT's technology is the significantly reduced material need, making the PEPperCHIP® platform definitely more cost-effective than any other peptide microarray technology.
The physical properties of the amino acid particles are precisely adjusted to conventional high-end laser printer toner particles. The particles are thoroughly analyzed with respect to size distribution, thermal characteristics, charge-to-mass ratio, and morphology guaranteeing highest demands on particle quality and state-of-the-art printing performance.