Identification of Condom Lubricants by FT-IR Spectroscopy

In many cases, especially those involving sexual assault, forensic scientists are searching the biological evidences such as blood, skin, hair, saliva, urine, semen for DNA analysis. Recently, the uses of condoms in sexual assault cases were increasing to avoid leaving the biological traces in the crime scene. In these cases, finding the condom lubricant traces from the victims can be valuable in sexual assault cases. It has been found that Fourier Transform Infrared Spectroscopy (FTIR) offers a nondestructive method of polymer identification. FT-IR spectroscopy was the main analytical technique used in majority of forensic laboratories. In this study, 35 condoms were purchased from various stores in Taiwan to analyze the lubricants. The results indicated that the majority condom lubricants used were polydimethylsiloxane (PDMS). The infrared spectra database of lubricants can be used to provide associative evidences between victim and sexual assailants.