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[Relationship between PMI and ATR-FTIR Spectral Changes in Swine Costal Cartilages and Ribs]
Objective:
To analyze postmortem chemical changes in Landrace costal cartilages and ribs using attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, and to provide a novel technique for estimation of postmortem interval (PMI).
Methods:
The swines were sacrificed by hemorrhage and their costal cartilages and ribs were kept in 20 degrees C. The chemical analysis of the costal cartilages and ribs were performed using ATR-FTIR every 72 h. The correlation between the certain spectral parameters and PMI was also analyzed. The time-dependent changes of costal cartilages were more significant than ribs.
Results:
There were no obvious changes for the main absorbance bands position, and some absorbance band ratios showed time-dependent changes and significant correlations with the PMI.
Conclusion:
ATR-FTIR has the ability to analyze postmortem chemical changes of the swine costal cartilages and ribs, and it can be a new method to estimate PMI based on spectroscopy.
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