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Microfluidic System for Automated Dye Molecule Extraction and Detection for Forensic Fiber Identification

NCJ Number
Date Published
November 2014
172 pages
This report presents the results and methodology of a project with the twofold purpose of producing a novel, reliable, and useful microfluidic system for fabric dye extraction and increasing the knowledge needed to guide criminal justice policy and practice related to the forensic analysis of dyed fabric.

The project succeeded in identifying and creating the optimum extraction conditions for different dyes and fabrics, and it developed an automated microfluidic dye extraction system that produces these conditions. This report provides information on the extraction solvent, the extraction chamber material, cavity shape, valve configurations, extraction temperature, and the macro fluidic extraction and analysis. The micro fluidic device connected directly to a high resolution mass analyzer or any other mass spectrometer enables automatic setting for the analysis of extracted dyes from fibers or a single fiber. The volume of solvent used to achieve the extraction and analysis is low (10 ml). The analysis of a sample can be done in 10 minutes. An advantage of this process is the lack of sample manipulation for the extraction of the dye, which prevents possible scenarios of contamination. The methods developed in this project are a step toward identification of dyes within fibers with minimal loss of fiber. The developed system enables objective comparisons of fiber dyes and a statistical error calculation useful in court testimony. Future work is required to determine the statistical rigor of the methods reported in this project. Extensive tables and figures, 57 references

Date Published: November 1, 2014