Development of a HPLC method for the separation of peptide nucleic acids

Peptide Nucleic Acids (PNA) are DNA analogues, combining a polyamide backbone (2-aminoethylglycine) attached via a methylenecarbonyl group to purine and pyrimidine nucleobases. PNA has a stronger affinity for its DNA compliment than doescomplimentary DNA itself. Consequently, PNAs have enormous potential for use as genetic probes, for gene therapy and antisense applications, among others. As a purification technique, High Performance Liquid Chromatography (HPLC) is facile, cheap and easily automated. Hence, HPLC can seemingly be a great technique for separation of PNA oligomers. The effects of various HPLC parameters, temperature, column type, and eluent composition and gradient, were investigated with respect to the retention time and peak resolution for PNA oligomers. Results show that as column temperature rises, the retention times fall and the peak resolution increase both linearly. HPLC peak resolution is also enhanced by using typical peptide conditions (acidic) as opposed to typical DNA analysis conditions (basic).