A highly sensitive magnetic nanoparticle based method for reliable and efficient screening of forensic evidence samples

The aim of the proposed project is to address the problem concerning the significant backlog of biological evidence, including Sexual Assault Kits (SAKs), present in local and state crime laboratories throughout the United States. Upon completion of this project, a sensitive, non-PCR based, non-destructive assay for detection and quantifying total male and human DNA will have been developed. The method is based on probe hybridization and enzymatic signal enhancement; hence the assay will be a non-destructive approach to evidence quantification. This can be of great value for low level DNA evidence sample processing, such as DNA swabs from gun casing and single fingerprint evidence. By utilizing a low-cost, non-PCR based assay that can rapidly screen biological evidence, crime scene investigation (CSI) units and crime laboratories can significantly reduce backlogs and focus on probative results in order to solve violent crimes. InnoGenomics proposes to develop a non-PCR hybridization based method utilizing functionalized nanoparticles, perform simple conjugations and DNA targeting with the use of fluorometric techniques. Features of functional magnetic nanoparticles (MNPs) include stability in solution and homogeneous dispersion in media, making them well-suited for bio-sensing. With functionalized MNPs, the ability to easily capture low concentrations of DNA (in the femto- and pico- molar range) has been shown to achieve comparable or better sensitivity than the current best qPCR detection systems. With a simple set up and ease of use to determine results, the ability to use functionalized DNA nanoparticles provides a greater advantage for detecting DNA in smaller quantities when compared to other methods in forensic evidence screening. Objectives of the project include identifying efficient and sensitive human and male DNA targets, protocol optimization, and evaluating the developed system with vari us types of mock and non-probative samples. Preliminary data demonstrates the systems ability to successfully sequester DNA from serially diluted samples and directly quantitate it without PCR amplification. Research to develop a low-cost system that can easily detect the presence and quantity of human DNA and human male specific DNA (with a high degree of sensitivity), will be of tremendous societal value to aid in the reduction of crime scene evidence backlogs, especially for sexual assault kits. This new test will have high sensitivity so that only a small portion of the collected evidence sample will be screened to find the most probative samples for DNA profile processing. This project contains a research and/or development component, as defined in applicable law. - See 2 CFR 200.210(a)(14). ca/ncf