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BioTek® Plate Washer Maintenance for SMC® Assays


The BioTek® plate washer maintenance for SMC® assays detailed below should only be used as a guideline and should be adapted to the requirements of individual laboratories. SMC® assays utilize the “cellular wash” function in the BioTek® washers, which uses smaller flow tubing. Therefore, to ensure the BioTek® washer is properly primed, it is recommended to use the “W-Day Rinse” protocol that dispenses a volume of 500 mL. You may have to evaluate whether you need to perform the bleaching protocol biweekly or monthly. This will depend on your throughput and if you have an increase in the coefficient of variation (CV).

Overview of Maintenance Procedure

The protocol is split into three parts:

  • Start and End of Day Maintenance
  • Biweekly Maintenance
  • Monthly Maintenance


Wash protocols are routinely set up as deionized water (DI Water) on washer port A and Wash Buffer on washer port B. Please confirm the setup of buffers before using this maintenance procedure.

Image of the BioTek® plate washer for SMC® assays used in the maintenance protocols.

Figure 1.The BioTek® plate washer for SMC® assays.

Start and End of Day Maintenance

The procedures outlined below should be completed by the operator.

Start of Day Maintenance

  • Prime with Wash Buffer
  • Select: Maintenance, W-Day_Rinse, this will prime tubing lines and press start
  • Volume: 500 mL total volume Buffer: B (Wash Buffer), Full System

Note: W-Day_Rinse is a simple one-step protocol to fully flush the system with water or reagent to keep the manifold tubes clog-free.

End of Day Rinse

  • Prime with DI Water
  • Select: Maintenance, W-Day_Rinse, and press start
  • Volume: 500 mL (minimum), Buffer: A (DI Water), Full System
  • Dampen a lint-free tissue with 70% ethanol or reagent alcohol and wipe down exposed surfaces of the BioTek® washer and magnetic plate
  • Select: Maintenance
  • Select program: Water Rinse & Soak or Water Shutdown Bottle A
  • Once the main screen shows “submerging tips” and a timer of 5 minutes starts, turn off BioTek® washer (switch in back)

Prior to Storage or As Required

  • Sonicate manifold (if Ultrasonic Advantage™ program is available)
  • Sonicate the manifold at the end of every day for 10-15 minutes
  • Select: Quick (Right side of the main menu, top button)
  • Sonicate Manifold tab
  • Clean Buffer: B (Wash Buffer), Rinse Buffer: A (DI Water), 10-15 minutes

Biweekly Maintenance

The procedures outlined below should be completed by the operator.

  • Turn on BioTek® washer (switch in back)
  • Rinse containers
  • Empty and rinse both DI Water and Wash Buffer container with DI Water
  • Refill both containers with their respective liquids
  • Screw on container lids, empty waste

Bleach Manifold (must be followed by Rinse Manifold)

  • Make ~1% Sodium Hypochlorite solution (or 10% solution of US household bleach) in a Wash Buffer container
  • Place both line A and line B into the bleach filled wash bottle
  • SMC® assays utilize the BioTek® washer’s “optimized cell washing” function to give a slower flow rate. This uses smaller tubing in the washer and a thorough rinse is required.

Prime System Line A

  • Select: Maintenance, W-Day_Rinse
  • Volume: 500 mL (minimum), Buffer: A (Line into bleach), Full System

Prime System Line B

Select: Maintenance, W-Day_Rinse, Prime System tab

  • Volume: 500 mL (minimum), Buffer: B (line into bleach), Full System
  • Rinse Manifold
  • Use a clean Water Rinse bottle (not the Buffer A water bottle to be used in your run) with DI water
  • Prime system Line A
  • Place both line A and line B into the Water Rise bottle
  • Select: Maintenance, W-Day_Rinse
  • Volume: 500 mL (minimum), Buffer: A (Line into Water Rinse bottle), Full System
  • Prime system Line B
  • Select: Maintenance, W-Day_Rinse, Prime System tab
  • Volume: 500 mL (minimum), Buffer: B (Line into Water Rinse bottle), Full System
  • Return Line A to the Buffer Bottle A (DI Water) and Line B to Buffer Bottle B (Wash Buffer)

Sonicate Manifold (if Ultrasonic Advantage™ program is available)

  • Select: Quick (Right side of the main menu, top button)
  • Sonicate Manifold tab
  • Clean Buffer: B (Wash Buffer), Rinse Buffer: A (DI Water), duration: 60 minutes (01:00 hour)
  • This step may not be required if Manifold has been sonicated at the end of every day for 10-15 minutes
  • Prime with DI Water
  • Select: Maintenance, W-Day_Rinse
  • Volume: 500 mL (minimum), Buffer: A, Full System
  • End of Day Rinse
  • Select: Maintenance
  • Select program: Water Rinse & Soak or Water Shutdown Bottle A
  • Once the main screen shows “submerging tips” and a timer of 5 minutes starts, turn off BioTek® washer (switch in back)

Monthly Maintenance

The procedures outlined below should be completed by the operator.

  • Decontaminate containers
  • Rinse containers 3x with DI Water and refill with their respective liquids

Pin Cleaning

  • Use the appropriate size pin to clean the short dispense pin and the longer aspiration pins after removing manifold from BioTek® washer
  • Removing manifold requires removing the spray shield, unscrewing all four manifold screws, and sliding both top and bottom manifold out simultaneously
  • Ream each aspirate and dispense pin with the appropriately sized pin and wash out sides of manifold with DI Water

Tips for Plate Washer Maintenance

  • If assay gradient issues are suspected, check that the carrier plate is level using a spirit level
  • Clean any dust or spillages from the magnetic plate with a soft clean toothbrush and DI Water
  • If washers are not in regular use, use the dust cover provided with the BioTek® washer
  • For high-throughput clinical studies, we recommend you contact BioTek® support for twice-yearly preventive maintenance (PM)



Learn more tips for using this plate washer in our BioTek® Plate Washer article .

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