Age estimation using aspartic acid racemization in various forensic samples: a preliminary study

Age estimation


  • YUTTI AMORNLERTWATANA Department of Forensic Medicine, Faculty of Medicine, Chiang Mai University
  • Churdsak Jaikang Department of Forensic Medicine, Faculty of Medicine, Chiang Mai University


Age estimation, Aspartic acid racemization, D-aspartic acid, L-aspartic acid, Forensic samples


Objectives To evaluate the potential of aspartic racemization to estimate age using different types of forensic specimens.

Methods Samples of blood, vitreous fluid and teeth were collected from cadavers and placed in 6 M hydrochloric acid before o-phthaldialdehyde- N-acetyl-L-cysteine (OPA-NAC) derivatization. D- and L-aspartic acid were determined by high performance liquid chromatography using a fluorescence detector. Linear regression was used to evaluate the relationship between the ln [(1+D/L)/(1-D/L)] value and chronological age.

Results A higher correlation was observed between aspartic acid racemization rates and age in dentin than in either vitreous fluid or blood with calculated error ranges of ± 4.5, 22.6 and 581.4 years, respectively. Dentin had a lower amino acid turnover rate than either the vitreous fluid or blood samples.

Conclusions Dentines can provide a more accurate estimation of age than either vitreous fluid or blood. Other low amino acid turnover rate tissues should be studied to determine their age estimation precision capacity.


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How to Cite

AMORNLERTWATANA Y, Jaikang C. Age estimation using aspartic acid racemization in various forensic samples: a preliminary study: Age estimation. Chiang Mai Med J. [Internet]. 2020 Jun. 26 [cited 2022 Jun. 29];59(2):53-9. Available from:



Original Article