Ultrasonicators for Forensic Investigations
- Ultrasonic devices are used for two major applications in forensic labs: for extraction and cleaning.
- Ultrasonic extraction is used to obtain targeted substances such as DNA, drug components or other active compounds.
- Ultrasonic cleaning is an effective tool to remove residuals and depositions from subject-matter.
Ultrasonic devices are a standard tool in well-equipped analytical laboratories. For forensic investigations, ultrasonics is mostly used to extract substances and to clean surfaces and microcracks.
Ultrasonic devices are a proven tool to extract active compounds, traces and residues from sample material, such as tissue, hair, blood, bones, and plants. Common applications of ultrasonic lab devices include the extraction of DNA, proteins, and active compounds such as drugs. Ultrasound is very effective to release cell-entrapped matter or bounded substances resulting in higher yields of extracts in shorter time. Its simple use as well as its reliability and reproducibility are major advantages of the ultrasound-assisted extraction technique. Click here to learn more about ultrasonic extraction!
Example: Extraction of Drug Residues
For forensic investigations, it is a recurrent task to test hair samples on residues of drugs. The extraction of drugs from hair is one of the most sensible steps of hair analysis as drugs are firmly enclosed in the hair structure and partly bound to proteins, melanin or lipids of the cell membrane complex. The extraction yield depends on the drug structure, the state of the hair matrix, pre-grinding steps, polarity of the solvent, and duration. The use of ultrasonics helps to assist higher extraction yields whilst reducing the treatment time. Therefore, ultrasound is a reliable method for the extraction applications in biological, clinical and forensic laboratories.
The graphic below displays the extraction yield obtained over a step-wise extraction of opiates (morphine, codeine, heroin, MAM) of a hair sample of a heroin fatality in methanol.
Ultrasonification is an excellent technique for the cleaning, conservation and restoration of metals, ceramics and other materials. The ultrasonic waves of an probe-type ultrasonic device allows for the precise removal of deposits from surfaces and small orifices. The mechanical cleaning forces of ultrasound can be applied with the sonotrode (probe) directly on surfaces and on small holes, (micro-)cracks and fissures removing unwanted crusts, debris, sediments or microbial contamination. Due to its exact and targeted application and its precise controllability of the ultrasonic intensity, ultrasonicators are not only used in forensic labs, but for the restoration and conservation of archeological findings, too. Easy handling and precisely controllable amplitudes ensure that a gentle yet effective cleaning is achieved.
- Mozayani, Ashraf; Noziglia, Carla: The Forensic Laboratory Handbook: Procedures and Practice. Springer Science & Business, 2006. 169.
- Pragst, Fritz (2004): Pitfalls in hair analysis. T + K 71/2, 2004. 69-81.
The work of forensic scientists and technicians include the examination and analysis of blood and hair samples, DNA, fingerprints, ballistics, hard drives, vehicles, toxins, controlled substances, blood splash patterns, trace marks and more. The obtained test results give important indications. This means, forensic laboratories provide objective evidence to help solve crimes, explain accidents and disasters for clients in law enforcement, government, and insurance companies.
The work areas of forensic laboratories branches out into the fields of criminalistics, botany, chemistry, dactyloscopy, DNA analysis, entomology, geology, limnology, pathology, podiatry, oxicology, serology, and toxicology.
Facts Worth Knowing
Ultrasonic tissue homogenizers are often referred to as probe sonicator/ sonificator, sonic lyser, ultrasound disruptor, ultrasonic grinder, sono-ruptor, sonifier, sonic dismembrator, cell disrupter, ultrasonic disperser, emulsifier or dissolver. The different terms result from the various applications that can be fulfilled by sonication.