The primary study of postmortem interval estimation by the lipid in puparium cases of Diptera：Calliphoridae / 中国法医学杂志

ABSTRACT

Objective To explore the value of lipidic degradation in puparium cases of C.megacephala during weathering in postmortem interval estimation. Methods The puparium cases of reared C.megacephala were collected, and laid outdoor. They were taken back 5 days and 10 days later, and then be stored at -20℃. The samples of control group were cleaned and cryopreserved immediately. The spectra were collected and preprocessed. The peak position and peak height were read and performed statistical analysis by SPSS 19.0 software. Results Compared to control group, the positions of Vas CH3 band showed no shift, and the Vas CH2 band showed blue shift, meanwhile, the Vs CH2 band disappeared in both experimental groups, moreover, the Vs CH3 band showed red shift only in 10d group;except of the Vs CH3 band in 5d group, the intensities of both the other two lipidic bands reduced in both experimental groups. Compared with 5day group, the Vs CH3 band showed red shift in 10d group, meanwhile, the differences of all the lipidic bands had statistical signiifcance. Conclusion Detection of lipidic degradation in puparium cases of C. megacephala during weathering by micro-FTIR provides a novel way to estimate postmortem interval and performs its potential for forensic applications.