Establishment of a Fast and Accurate Proteomic Method for Body Fluid/Cell Type Identification

• NCJ Number: 236538
• Author(s): Mechthild Prinz, Ph.D.; Yingying Tang, M.D., Ph.D.; Donald Siegel, Ph.D.; Heyi Yang, Ph.D.; Bo Zhou, Ph.D.; Haiteng Deng, Ph.D.
• Date Published: 2011
• Length: 62 pages
• Grant Number(s): 2008-DN-BX-K011
• Agencies: NIJ-Sponsored
• Publication Type: Report (Study/Research)

Annotation

This project's overall objective was to determine whether a single, confirmatory methodology, using mass spectrometry (MS) as the means of detection, could be developed for the identification of five forensically important body fluids: blood, saliva, semen, menstrual blood, and vaginal fluid.

Abstract

The steps involved in achieving this objective were to identify multiple protein markers for each body fluid; determine the limit of detection for each body fluid; establish a single extraction procedure that works well for all body fluids on a variety of substrates; determine limits of detection for each body fluid in mixed samples; evaluate aged mock forensic samples; and establish a high throughput assay. The results of these efforts show the value of MS as a routine tool for body fluid identification. Multiple markers were identified for blood, saliva, and semen; and a common method was developed for their extraction from all five substrates (cotton, polyester, condom, common beverage plastic, and wood). Detection levels for these three body fluids were in the nanoliter range, which is lower than other methods currently used. Body fluids mixtures could be distinguished, and aging for up to 20 months did not significantly affect sample detection. In addition, preliminary results indicate that all three body fluids are amenable to high throughput testing. Researchers also identified multiple markers in menstrual blood (five) and vaginal fluid (seven); however because protein expression is known to vary in response to hormone levels, further investigation of these potential markers throughout the menstrual cycle is required. Thus, these findings indicate that MS can be used as a single confirmatory body-fluid assay that could replace the current test methods. This would simplify standardization for body-fluid testing across laboratories. 10 tables and 62 references