U.S. flag

An official website of the United States government, Department of Justice.

Automated Processing of FTA Samples

NCJ Number
241347
Author(s)
Erin Finehout; Perry Bonanni; Scott Duthie; Weston Griffin; Zaeem Khan; Phil Shoemaker; Xuefeng Wang
Date Published
February 2013
Length
27 pages
Annotation
This project designed a system for automating the processing of FTA cards in forensic DNA data-banking applications.
Abstract
The proposed system allows a user to load a stack of FTA EasiCollect cards in the system and then receive a 96-well plate of punches ready for PCR. The prototype of the system includes the following subsystems: card manipulation, well-plate handling, sample locating, well-plate static removal, card punching, fluid addition, and dust removal. The subsystems were integrated, and the resulting prototype was tested for sample loss, cross- contamination, and compatibility with downstream STR analysis. The system was effective in reducing the risk of sample loss from static effects. The final estimated error rate was less than 0.15 percent. Tests that evaluated cross-contamination found that a cleaning punch between samples reduces the cross contamination risk and that the current vacuum system requires some improvement in order to prevent general dust buildup. The final test used the system in order to punch FTA cards that contained buccal swabs. All of the tested samples produced full STR profiles. The prototype tests were used to develop a conceptual design for a next-generation prototype. Having a system that enables automation of FTA card handling could improve the throughput of sample processing of DNA data-banking forensic labs. By having the automated system work reliably with the smallest size punch (1.2 mm), labs would also be able to minimize their reagent costs. The cost savings would result from both using smaller volumes of the PCR reagents and from having fewer "lost" punches, which would mean fewer sample re-runs. 12 figures, 4 tables, and 3 references