Integrated Microfluidic System for Rapid Forensic DNA Analysis: Sample Collection to DNA Profile

Abstract

We demonstrate a conduit for the delivery of a step change in the DNA analysis process: A fully integrated instrument for the analysis of multiplex short tandem repeat DNA profiles from reference buccal samples is described and is suitable for the processing of such samples within a forensic environment such as a police custody suite or booking office. The instrument is loaded with a DNA processing cartridge which incorporates on-board pumps and valves which direct the delivery of sample and reagents to the various reaction chambers to allow DNA purification, amplification of the DNA by PCR, and collection of the amplified product for delivery to an integral CE chip. The fluorescently labeled product is separated using micro capillary electrophoresis with a resolution of 1.2 base pairs (bp) allowing laser induced fluorescence-based detection of the amplified short tandem repeat fragments and subsequent analysis of data to produce a DNA profile which is compatible with the data format of the UK DNA database. The entire process from taking the sample from a suspect, to database compatible DNA profile production can currently be achieved in less than 4 h. By integrating such an instrument and microfluidic cartridge with the forensic process, we believe it will be possible in the near future to process a DNA sample taken from an individual in police custody and compare the profile with the DNA profiles held on a DNA Database in as little as 3 h.

The future of forensic DNA analysis

“…In the past few years, instrumentation providing a fully automated DNA profiling system has been introduced [28][29][30][31]. These rapid DNA instruments integrate the steps of DNA extraction, rapid PCR amplification of 15 or more STR loci, DNA separation, detection, sizing and genotyping.…”

Direct and label-free monitoring oligonucleotide immobilization, non-specific binding and DNA biorecognition

“…and label-free monitoring oligonucleotide 1 immobilization, non-specific binding and DNA biorecognition 2 3 José Luis López-Paz, Miguel Ángel González-Martínez * , Jorge 4 Escorihuela, María-José Bañuls, Rosa Puchades, Ángel Maquieira DNA binding chemistry on silicon surface has been investigated. Aminated 12 oligonucleotide probes were immobilized on the chip surface by chemical silanization and 13 further covalent attachment.…”

Noise analysis and measurement of integrator-based sensor interface circuits for fluorescence detection in lab-on-a-chip applications

“…The requirements for large-scale bench-top infrastructure, expert operators and costly reagents has restricted assay analysis to large, well-funded laboratories. In recent years, however, there has been a surge in the development of point-of-care (POC) diagnostic devices for applications in medicine [1], forensics [2] and food safety [3].…”