Evaluation of DNA in Collagen Products

Evaluation of DNA in the following products:

• PureCol^®  3 mg/ml type I bovine collagen, Catalog #5005
• PureCol^®-S 3 mg/ml type I bovine collagen standard, Catalog #5015
• VitroCol^® 3 mg/ml type I human collagen, Catalog #5007
• Nutragen^® 6 mg/ml type I bovine collagen, Catalog #5010
• FibriCol^® 10 mg/ml type I bovine collagen, Catalog #5133

Nuclei acids are known to be susceptible to extremes in pH. DNA is degraded at low pH while RNA is quite susceptible to high pH. The collagen products listed above undergo processing at both low pH and high pH where likely degradation of any DNA takes place. A study was performed to confirm this.

Method:
Human DNA was incubated in pH 2 hydrochloric acid (HCl) for 7 days at 18°C. This is the minimal time that the above listed collagen products are subjected to pH 2 during processing. The samples were then neutralized and analyzed by gel electrophoresis. To evaluate the effects of high pH, DNA was incubated for a time period at 20°C in sodium hydroxide (NaOH). These samples were then neutralized and analyzed by gel electrophoresis.

Results:
The results indicate that the HCl treated DNA samples were completely degraded and the DNA in the NaOH treated samples were partially degraded under the conditions used to process the collagen.

Conclusion:
The study demonstrates that DNA is completely destroyed at pH 2. The DNA was significantly reduced under the conditions in which it was treated with NaOH. This study provides good assurance that the collagen processing clears DNA in the collagen products.