Magnetic Separation Methods for the Detection of Mycobacterium avium subsp. paratuberculosis in Various Types of Matrices: A Review

Table 6

Magnetic separation method used for the detection of Mycobacterium avium subsp. paratuberculosis DNA in feces and tissue.

Type of kit	Type of matrix	Artificially contaminated	Preparation of sample	Initial volume of sample	Initial number of MAP [MAP/mL]	Limit of Detection [MAP/mL]	Sensitivity of detection [%]	Reference
MagMAX	Bovine feces	No	No preparation	500 µL	n. a.	n. a.	65	[43]
		No	300 mg of feces diluted in 1 mL of PBS, vortexed, centrifuged, supernatant added to a tube with zirconia beads and lysis-binding solution, vortexed, centrifuged, added to a plate with isopropanol, magnetic nucleic acid-binding beads and binding lysis enhancer, automated system used (MagMAX Express Magnetic Particle Processor)	300 mg	n. a.	n. a.	76	[14]
BioSprint 96 + MagMAX-96 auto.	Bovine feces	No	Growth in Bactec 12B, 200 µL liquid culture medium added to 200 µL buffer RLT, transferred to a tube with 0.3 g zirconia/silica beads, disrupted in Fast Prep-24 bead beater for 60 s, and centrifuged, 100 µL added to a deep 96-well plate	100 µL	n. a.	n. a.	n. a.	[44]
	Sheep feces	No		100 µL	10^6 to 10^1	100–1000	n. a.
	Sheep tissue	No		100 µL	n. a.	n. a.	n. a.

MagMAX Total Nucleic Acid Isolation Kit; BioSprint 96 one-for-all vet kit (Qiagen) + MagMAX-96 automated magnetic processor; artificially contaminated only to set the Limit of Detection; auto = automatically processed; LOD = Limit of Detection; MAP = Mycobacterium avium subsp. paratuberculosis; n. a. = not available; PBS = phosphate-buffered saline; RLT = commercial name for the lysis buffer (Qiagen).