ERP Micro December 2019

samples and BTS have dried, HCCAMatrix solution must be added within 30 min, or the target must be cleaned and the inoculation of samples and BTS must be repeated. ( m ) Overlay each sample position and BTS control positions with 1 μL HCCAMatrix. Use a new pipet tip to add matrix to each inoculated sample position. ( n ) Dry the inoculated target at room temperature (20–25°C). ( o ) The inoculated target is now ready for use. Note : An inoculated target must be processed within 24 h of preparation, or the target must be cleaned and the inoculation of samples and BTS must be performed again. The sample positioning on the target can be facilitated with the MBT Pilot™ workstation. J. Generating a Run Result Report ( a ) After the acquisition of the target has been completed, click View > Results to generate a PDF report. ( b ) The PDF report header contains the Run Identifier and Run Creation Date/Time from the Run Info section. ( c ) The PDF report footer contains the report creation date/time, page count, and the appropriate area of application. References: J. AOAC Int . 101 , 1593(2018) DOI: 10.5740/jaoacint.18-0012 (First Action) J. AOAC Int . 102 , 1595(2019) (Revised First Action) DOI: 10.5740/jaoacint.18-0329 Posted: March 2018, October 2018, August 2019 (Revised First Action after publication in J. AOAC Int.)

I. Formic Acid/Ethanol (Tube) Extraction Sample Preparation ( a ) If the identification received is still below 1.7 after the eDT, the isolate should be reanalyzed following the EXT procedure. ( b ) Transfer 300 µL HPLC grade water to a microcentrifuge tube. Transfer colonies from the agar plate into the water to create a cell suspension of approximately 1.5–2 McFarland. ( c ) Add 900 µL ethanol and mix suspension. ( d ) Centrifuge the suspension for 2 min at 15871–21130  g (equivalent to 13000 to 15000 rpm for Eppendorf tube centrifuged with a 5424R rotor). Decant the ethanol. ( e ) Repeat step ( d ) to remove all residual ethanol. Avoid contact with the pellet. ( f ) Air-dry the pellet for a minimum of 5 min at room temperature (20–25°C). ( g ) Add 25 µL of 70% formic acid and pipet up and down to resuspend the pellet. Vortex thoroughly and let stand for 5 min at room temperature (20–25°C). ( h ) Add 25 µL of 100% acetonitrile and mix by pipetting up and down 2–3 times. ( i ) Centrifuge 2 min at 15871–21130  g (equivalent to 13000 to 15000 rpm for Eppendorf tube centrifuged with a 5424R rotor). ( j ) Dispense 1 µL of sample onto the target, i.e., cleaned reusable steel target or disposable Biotarget 96. ( k ) A valid BTS control is mandatory per target and run, therefore it is advised to use two BTS control positions. Select the BTS control positions on a target to inoculate with BTS solution. ( l ) Pipet 1 μL of reconstituted BTS solution onto the two selected positions and dry at room temperature (20–25°C). Note : After

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