Why M-Vac

Bardole DNA Collection Method

The following was developed by Francine Bardole of the West Jordan Utah Police Department with support from M-Vac Systems. It is a method of separating and isolating DNA material from small evidence items. The application could include many items that are currently difficult to sample like shell casings, fingernail clippings, rings, gun parts, keys, bomb fragments and other small items. Here is a summary of how it works.

The Bardole Method Overview:

  1. Shell Casing AgitationAdd sterile SRS buffer to an M-Vac collection bottle*
  2. Place place the evidence item in the bottle
  3. Agitate the bottle
  4. Attach a concentration filter to the SEC vacuum hose and turn ON the vacuum
  5. Swirl and pour the liquid portion of the collection bottle into the concentration filter cup
  6. If the evidence item is heavy or sharp, trap the item with the cap of the bottleFiltering a Shell Casing, so that is does not fall onto the filter membrane and potentially damage the integrity
  7. The DNA material is retained on the filter membrane
  8. If there are multiple items, repeat the process
  9. When finished, remove the concentration filter from the vacuum tube and cover to dry

Later, when it is time to process the filter membrane, it will be cut out of the concentration filter apparatus and processed in the same manner as a swab or other DNA evidence gathering method is processed.

*It is important to note, that the size of the item being processed will determine the size of the bottle and the amount of buffer to be used.  There must be enough room and buffer for sufficient agitation to happen.

Continuing Research

A multiple agency project is underway with a larger data set of shell casings to further determine the sensitivity of the method.

Adjudicated Case

Bardole Shell 2Ten casings from a road-rage shooting were processed using the method described above. The extraction quant yielded 0.847 ng of DNA. The amplified results yielded a comparable major profile that matched the suspect. The evidence was presented in court, challenged and accepted.Shell Casing Result Summary

References:

https://www.forensicmag.com/news/2018/04/dna-spent-shell-casings-matter-getting-nooks-and-crannies