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HomeSingle Molecule Counting (SMC®) TechnologySMCxPRO® Platform: Best Practices

SMCxPRO® Platform: Best Practices

The SMCxPRO® instrument is the next generation instrument beyond the Erenna® immunoassay system and employs the unique Single Molecule Counting (SMC®) technology to meet your low sensitivity needs. Offering several advantages including fluidics-free sample acquisition, faster read-times, and compact instrument footprint, the SMCxPRO® instrument is also easy to use, 21CFR part II compliant, and LIMS compatible. Uncover best practices on SMCxPRO® instrument use, including basic instrument maintenance guidelines, Aurora reader plate handling, and general information regarding SMC® assays.

SMCxPRO® Instrument Recommendations

The SMCxPRO® unit should be positioned in the lab at least 10 inches from the back wall to allow proper airflow behind the unit. It should not share a benchtop with any other equipment that shakes or causes vibration. When powering up the unit at the beginning of the day, allow the instrument to warm up for 90 minutes before use.

Run the ASSIST application at the start of each day of use to ensure your SMCxPRO® instrument and its components are operating within an acceptable range. Air drafts or long periods of non-use may cause the ASSIST Thermal Stability Test to fail the first time it is executed. If this occurs, leave the instrument idle for 30 minutes and then re-run all ASSIST tests.

ASSIST diagnostics will test some instrument components that are not involved in regular data acquisition, similar to the “Check Engine” light on your car. If your SMCxPRO® unit fails some ASSIST parameters beyond instrument temperature, notify our Technical Support Team or your Field Application Scientist (FAS). In cases of a time-sensitive experiment, the instrument can still be used if the calibrator plate test passes.

Calibrate the SMCxPRO® unit at the beginning of each day the instrument is in use.

Watch a Video on How to Set Up and Calibrate the SMCxPRO® Instrument

Watch this short video for an easy step-by-step guide to setting up and calibrating the SMCxPRO® instrument.

How to Handle Aurora Reading Plates

SMC® assays are prepared in 96-well bottom Axygen plates until the end of the protocol, where eluted and neutralized samples will be transferred to 384-well plates for acquisition. Aurora 384-well plates are the only compatible 384-well read plate for the SMCxPRO® instrument. Each plate will include a black lid which should be kept under the plate to protect well bottoms from scratches, fingerprints, dust, and debris. Cover the Aurora plate wells immediately after removing them from packaging to minimize exposure to open air, lint, and dust.

Use only aluminum adhesive seals for assay plates that will be read on SMCxPRO® instruments or assay plates that you will store and read later. Do NOT use clear acrylic seals to seal loaded Aurora plates because they do not protect against light. The paint inside the instrument hood is reflective and will disrupt signal acquisition.

Image of the Aluminum adhesive seal needed for Aurora assay plates read on SMCxPRO® instruments. Do NOT use clear acrylic seals to seal loaded Aurora plates because they do not protect against light.

Figure 1.The aluminum adhesive seal that is needed for Aurora assay plates read on SMCxPRO® instruments.

To ensure optimal acquisition precision, it is important to seal the read plate completely and uniformly to prevent well evaporation and cross-well condensation which may occur if each well is not fully sealed.

To achieve complete sealing for each well:

  1. Use the recommended aluminum adhesive seals and plate roller
  2. Remove the backing of the seal and center the seal smoothly over all 384 wells without creating any creases, folds, or kinks.
  3. Run fingers across the seal on the plate to secure placement, then create a complete seal by rolling the plate roller across the entire face of the plate:
    1. First, in a vertical direction
    2. Then, in a horizontal direction of the plate
      1. Hold the plate down with one hand. Tilting the plate roller on the plate with the other hand, use the soft corner of the silicone padding and migrate from one end of the plate to the other, vertically, then horizontally.
      2. Pay close attention to the junctions and corners of the outer edge wells and the plate frame.
      3. A complete seal will have a concave appearance across all wells, and all rims and well wall corners will be clearly visible.

Firmly and carefully place your loaded Aurora plate containing sample into the Tray Load Portal, ensuring that all four corners are seated properly. If the plate is tilted during the well scan, data collection will be compromised, and the software may return an error.

In addition, flip up the perforated side strips of the aluminum adhesive seals before seating your plate into the instrument to prevent potential acquisition issues due to plate alignment.

Pulse centrifuge Aurora plates after each read to pull down any product condensation between reads. Carefully handle Aurora read plates to prevent disturbing the liquid contents.

FAQs on SMC® Assays

How do I avoid interference in signal detection?
Thorough elution and neutralization of immunoassay complexes and proper sample transfer to the Aurora read plate are essential to achieve stable, reproducible well RESPONSE signals and ensure intra-assay precision. Detailed neutralizations may be found within the kit protocol.

To avoid interferences in signal detection, avoid air bubbles when transferring the neutralized eluate to the Aurora read plate by aspirating and dispensing slowly using a P20 multichannel pipette. If bubbles persist, use air from a P1000 pipette to resolve them before applying the final read plate seal.

Can I skip the warm-up period?
After initiating an assay run through the SMCxPRO® software, the SMCxPRO® instrument will warm up the read plate briefly so that it matches the operating temperature of the instrument. It is not recommended to skip this warm-up period as temperature inconsistencies can result in unwanted signal drift.

Can SMC® assays be read multiple times?
SMC® assays can be read multiple times on SMCxPRO® instruments. Pulse centrifuge Aurora plates between reads to recover, evaporate, and minimize photobleaching.

How do I store eluted products?
Eluted products from most SMC® assays can be stored with the seal facing upward overnight at 4 °C or frozen at -80 °C for later reading. Handle loaded plates gently, ensuring a complete seal on every well and pulse centrifuging plates containing eluted product before storage to maintain the integrity of the results. Additional protection can be ensured by bubble wrapping and/or zip-locking plates prior to storage.

When returning a loaded read plate from storage at 4 °C, be sure to leave it at room temperature for 30 minutes to 1 hour on the benchtop before reading to avoid a rapid increase in temperature within Aurora plate wells.

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For Research Use Only. Not For Use In Diagnostic Procedures.