Testing the limits of the ninhydrin method for radiocarbon dating degraded and contaminated bone

We aim to test whether a method involving the chemical ninhydrin which selects amino acids, the building blocks of proteins, can:

  1. recover sufficient carbon from extremely degraded protein in Australian bones for radiocarbon dating.

Radiocarbon methods for dating bone select the protein collagen. Most were developed in northern Europe/America where collagen is well preserved in temperate climates. In the warmer climate of Australia, collagen breaks into fragments that dissolve and are lost if exposed to water. However, if dry or physically protected, the fragments may remain. Unfortunately these cannot be dated with the traditional methods. However it is possible that a technique aiming to select amino acids and avoiding some of the more aggressive steps of the routine preparation of collagen will enable sufficient proteaceous carbon to be recovered from degraded bones. The ninhydrin technique will be tested initially on material from Cloggs Cave, Victoria (e.g. Simosthenurus mandible in the image).

  1. remove glue and humic contaminants from bone to enable accurate radiocarbon dating of Pleistocene fossils

The routine ultrafiltration protocol used to extract and purify bone collagen prior to dating cannot remove large quantities of humic contaminants which affect the dating of bone from e.g. bogs, or glues and consolidants used during conservation in the field and/or museum environments. High performance liquid chromatography is the only method that has been successful in removing such contamination (e.g. Marom et al. 2012). Unfortunately the method is complicated, requiring specialist technicians and expensive equipment. We aim to test whether the much simpler ninhydrin protocol is effective in removing such contamination.


  • Josephine Flood, Emeritus Faculty, ANU
  • Melbourne Museum, Victoria
  • Funded by the Ian Potter Foundation (2013-2014).