[Quantification of residues DNA in animal-derived biological scaffold materials]

Quantification of residual DNA in animal-derived biological scaffold materials is one of technical specifications for evaluating decellularization process and immunotoxicity risk. Up to now, there have been no standard methods available for quantification of residues DNA in animal-derived biological scaffold materials. In this study, a three-step method, including proteinase K digestion, DNA purification and determination of DNA using fluorescence assay, was designed for residual DNA quantification. A parallel recovery experiment of standard DNA using the same protocol to test article determination was used for adjusting final results of residuul DNA amount. DNA purification based on magnetic beads enabled the experiments to get high accuracy and repeatability. The validation experiment showed that the three-step method had high sensitivity up to 6.25ng of DNA per sample with good linearity (recovery curve R2 > 0.99) in the concentration range of 3. 125-100ng, and 25-400ng per sample. This method is useful for determining micro or trace amount DNA remained in the biomaterials.