Electrospray and MALDI mass spectrometry in the identification of spermicides in criminal investigations.
Electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI) mass spectrometry have been used to examine evidence in a sexual assault investigation. Because condoms are being used increasingly by sexual assailants and some condom brands include the spermicide nonoxynol-9 (nonylphenoxy polyethoxyethanol) in the lubricant formulation, the recovery, and identification of nonoxynol-9 from evidence items may assist in proving corpus delicti. A method was developed for the recovery of nonoxynol-9 from internal vaginal swabs and for its identification by reverse phase liquid chromatography/electrospray ionization mass spectrometry (LC ESI-MS), nanoelectrospray ionization (nanoESI) mass spectrometry, and high resolution MALDI Fourier transform mass spectrometry (MALDI-FTMS). The method was tested on extracts from precoitus, immediate postcoitus, and four-hours postcoitus vaginal swabs provided by a volunteer whose partner does not normally use condoms, but for this trial used a condom having a water-soluble gel-type lubricant that includes 5% nonoxynol-9 in its formulation. Subsequently, LC ESI-MS was used to identify traces of nonoxynol-9 from the internal vaginal swab of a victim of a sexual assault.
Hollenbeck
T P
TP
Scripps Research Institute, Beckman Center for Chemical Sciences, La Jolla, CA, USA.
Siuzdak
G
G
Blackledge
R D
RD
D017280:Condoms; D005260:Female; D005554:Forensic Medicine / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D006801:Humans; D008297:Male; D017137:Nonoxynol / Q000032:analysis* / Q000737:chemistry; D011902:Rape / Q000175:diagnosis* / Q000331:legislation & jurisprudence; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods; D013089:Spermatocidal Agents / Q000032:analysis* / Q000737:chemistry
D013089:Spermatocidal Agents; D017137:Nonoxynol