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DNA Extraction for Telemedicine Security. Tofy Mussivand, FRSC Professor of Surgery & Engineering Chair, Medical Devices Centre, University of Ottawa Director, Cardiovascular Devices Division, University of Ottawa Heart Institute. Working Hypothesis.
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DNA Extraction for Telemedicine Security Tofy Mussivand, FRSC Professor of Surgery & Engineering Chair, Medical Devices Centre, University of Ottawa Director, Cardiovascular Devices Division, University of Ottawa Heart Institute
Working Hypothesis A portable, rapid, device based system for DNA extraction from invasive and non-invasive (e.g. fingerprints) samples can be developed for wide-ranging applications in both medical and non-medical fields.
Required Functions/StepsFor Device Based DNA System 1) Cell sample collection (from fingerprint or other sources) 2) Lysis of cell membrane 3) Extraction of (nuclear) DNA 4) Purification of DNA 5) Restriction enzyme operation (Cleavage of DNA strings into recognition sequence) 6) PCR (Polymerase chain reaction) Replication and amplification of DNA 7) DNA detection and identification
DNA Testing Delays News Headlines • April 2005 - Washington State University researchers uncover huge unsolved crime DNA testing backlog (Washington State University News Service) • May 2006 - Delays in obtaining forensic evidence adversely affecting justice system (Auditor General, Australian Government) • May 2007 - DNA labs facing huge backlog: Canadians and Americans failing to meet target processing times… (The Scientist) • Feb 2008 - Lansing serial killing suspect's trial delayed for DNA analysis (WSBT News)
Major Delays • Royal Canadian Mounted Police (RCMP): • Average turnaround time: 114 days • Target turnaround time: 30 days • Federal Bureau of Investigation (FBI): • Average turnaround time: 1 year • Target turnaround time: 60 days. Source: The Scientist. May 21, 2007
Developed technique “SampleRelease” to lift the skin debris Skin debris deposited on a plastic surface after finger applied Same surface following application of the “Sample Release” technique Light Microscope X 20 Magnification 1st Question: Can DNA be obtained from non-invasive sources (fingerprints) ?
Next Question: Can sufficient DNA be extracted from skin debris ? Working Threshold (10 ng)
Next Question: Can this DNA sampling and extraction be performed rapidly ? 16 hrs. 13 hrs. 45 min. 15 min.
DNA Sampling & Extraction Process Validation • Process results validated by an independent 3rd party: • National DNA Data Bank operated by the Royal Canadian Mounted Police (RCMP)
Current Focus Integration of Developed Techniques into a Portable Device Based System
First Challenge: Microfluidics based Cell Membrane Lysis to Extract DNA A 10 sec. video clip taken with a 20X microscope Control Cell Cell exposed to newly developed technique The membrane of the cell exposed to this newly developed technique is lysed within ~ 6 seconds, while the control cell is not lysed
Next Steps: Cell Membrane Lysis using a new microchip developed by the Medical Devices Centre • MUMPs Technology or Multi User MEMS processes • MEMS = micro-electro-mechanical systems • MetalMUMPs = 20 micron thick nickel electroplating construction process cm
Overall Device Status 15 minute Extraction (Original Target): Rapid sampling & extraction method developed 3rd party validation of results by RCMP Patents applied for Canada, US, Japan, Europe (Method and apparatus for collecting cells for macromolecular analysis) 15 second Extraction (Current Target): Preliminary development of rapid cell membrane lysing technique suitable for a portable device Microchip prototype developed and system testing underway Additional work underway on overall device integration and prototype development 15
The DNA/Telemedicine Connection • Original Concept: Needed security method for artificial heart telemedicine system • DNA seemed to be the most secure approach • The importance of telemedicine security is highlighted in recent media reports that outline successful hacking of implantable medical devices including the ability to: • Deliver ICD shocks, or • Turn off the device • This work entitled “Pacemakers and Implantable Cardiac Defibrillators: Software Radio Attacks and Zero-Power Defenses” will be presented at the upcoming 2008 IEEE Symposium on Security and Privacy in Berkeley in May • The publication was released early online at: www.secure-medicine.org Wednesday March 12, 2008
Specific Telemedicine Examples for a Portable DNA Extraction Device • Telemedicine Security: Prevent unauthorized access to telemedicine systems, including for control/monitoring of life critical devices. • Other BioSecurity: DNA is considered by some to be the “holy grail” of biometrics. Data could be transferred for comparisons to central identity databases. Biosecurity apps include everything from secure facilities access to transportation safety. • Population Mapping: The ability to map large communities for specific genetic variants associated with various health conditions could be accomplished easily with a portable DNA sampling and extraction device. Data could be transferred from the field in real-time to international research centres.
Summary & Conclusions • New techniques for rapid (15 minute) DNA sampling and extraction have been developed and validated • The ability to obtain DNA from both invasive and non-invasive (fingerprint) samples has also been demonstrated • Work is proceeding for a 15 second DNA extraction system utilizing microchips for a portable device based system • Microfluidics based cell membrane lysis (6 seconds) has been demonstrated at the microchip level • A wide variety of potential applications in medical and non-medical fields are possible • Utilization of the DNA system could provide vital security for life critical telemedicine applications • Further work is currently underway