Decontamination of Surgical Instruments with MIDAS

Demonstration of MIDAS technology under laboratory conditions

These new methods for cleaning surgical instruments completely remove protein contamination, including prions – the infectious agents that cause Creutzfeldt-Jakob Disease (CJD) in humans.

The MIDAS methods, that were developed at the University of Edinburgh, use radiofrequency (RF) gas-plasma technology and are highly effective in removing contamination, including protein, from a variety of surfaces. Biological assays using infective implants have verified that the technique eliminates TSE infectivity.

Prion diseases are resistant to inactivation by conventional chemical and physical decontamination. This creates a risk of cross-contamination from instruments used during surgical procedures on patients.

Conventional sterilisation does not deactivate the infective agent of prion diseases. Many instruments must, therefore, be removed entirely from service. MIDAS technologies involve a series of pre-treatments, followed by exposure of the surgical instruments to RF plasma. The plasma treatment scours the surfaces, breaking down any biological tissue and converting it to non-toxic gases. Test samples pre-contaminated with TSE infective brain tissue and then treated using the MIDAS method show that contamination has been eliminated.

The technique can remove contaminating biomolecules from stainless steel surfaces (to levels a thousand times lower than those achieved by existing methods) and leaves no visible trace of any residual contaminated material. Verification techniques include SEM, spectrofluorimetric detection and biological TSE infectivity testing conducted by an independent laboratory.


  • Sterilisation of metal instruments used in surgery, dentistry or food preparation

Key Benefits

  • Removal of all protein contamination, including prions
  • Surgical instruments can be re-used
  • Stock-piled instruments can be brought back into service
  • Metal instruments are not damaged by the plasma techniques

Key Publications

Surgical Instrument Decontamination: efficacy of introducing an argon:oxygen RF gas-plasma cleaning step as part of the cleaning cycle for stainless steel instruments. Baxter et al IEEE Trans. Plasma Sci., 2006, 34, 1337- 1344.

Terms & Conditions

A datasheet describing the method for the decontamination of instruments employing the MIDAS method will be provided following acceptance of the terms and conditions.

University Services Available

Researchers are also developing spectrometer technology for the sensitive detection of surface biomaterial. Please get in touch to discuss opportunities for collaborative research or licensing.

This technology is available to access under the University's Open Technology initiative.

Request Access To This Technology

To access this technology under the 'Open Technology' initiative from ERI, simply complete the Open Technology Request Form, accepting the terms and conditions applicable to this technology.

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