How can I determine the concentration of a PNA solution?
The concentration of PNA solutions should be measured spectrophotometrically by reading the sample absorbance at 260 nm. To measure exclusively the PNA molecules in solution, the PNA stock should be centrifuged at 12,000 x g to first sediment any aggregated PNA molecules before diluting for OD measurement. Each PNA sequence has its own specific extinction coefficient that is different from a DNA oligomer of the same sequence due to the chemical differences. For further details on determining PNA concentrations, refer to Appendix B of the handbook supplied with the GeneChip Globin Reduction Kit.