MACS Matchmaker
Maintenance
Regular maintenance of the MACS Matchmaker ensures optimal performance and longevity of the instrument. A cleaning of the MACS Matchmaker and MACS Sampler is recommended after working with complex media such as blood or cell lysate. Furthermore, we recommend to perform a cleaning of the fluidics system at least once a month. Cleaning solutions and maintenance cartridges can be ordered from the Lino Biotech webshop. The following maintenance procedures are recommended:
- Fluidic System Cleaning: Requires cleaning using MACS Matchmaker cleaning solutions (Clean 1 and Clean 2) and the maintenance cartridge. Follow the cleaning protocol in the MACS Matchmaker software in the Liquid Handler under "Clean Fluidic System". This should be performed after each run with complex samples and at least once a month. When the fluidic system has not been cleaned for over a week since it was last used, MACS Matchmaker reminds you to run Clean Fluidic System. The Liquid Handler page also shows when Clean Fluidic System last ran and how many times it ran in the last 3 months.
- Rinsing After Each Use:Flush the fluidics system with ultrapure water by running the rinsing protocol in the MACS Matchmaker software in the Liquid Handler under "Flush Fluidic System" to remove residuals from previous samples. When the fluidic lines have been idle for several hours after an experiment, MACS Matchmaker reminds you to run Flush Fluidics. The Liquid Handler page also shows when Flush Fluidics last ran and how many times it ran in the last 30 days. If a dedicated wash port is configured on the pump distribution valve (in the pump configuration), MACS Matchmaker instead flushes the fluidics automatically after every experiment that ran injections, drawing washing solution from the wash port; the manual reminder is not shown after such a wash. An experiment without injections leaves the fluidics clean, so it is not washed automatically and the manual reminder still applies.
- Short-term Storage (Up to 24 hours): Perform rinsing procedure using the maintenance cartridge and ultrapure water.
- Long-term Storage: Decontaminate the instrument, then run 20% ethanol through the system.
- Surface Cleaning: Outer surfaces can be disinfected using 70% isopropanol or 70% ethanol.
Maintenance Schedule
| Frequency | Task | Details |
|---|---|---|
| After each use | Flush fluidics | Run the "Flush Fluidic System" protocol with ultrapure water to remove sample residuals. |
| After complex samples | Full cleaning | Run the cleaning protocol with Clean 1 and Clean 2 using the maintenance cartridge after blood, serum, plasma, or cell lysate. |
| Weekly | Inspect consumables | Check MilliQ wash bottle level, waste bottle fill level, and running buffer supply. Replace or refill as needed. |
| Monthly | Preventive fluidic cleaning | Perform full cleaning protocol (Clean 1 and Clean 2) even if only simple buffer samples were used, to prevent buildup. |
| Monthly | Inspect tubing and connections | Check for wear, discoloration, or loose fittings on all fluidic connections. Replace tubing if degradation is visible. |
| Weekly | Syringe pump cleaning | Clean the MACS Matchmaker syringe pump: insert the maintenance cartridge, then flush with 0.5% SDS → 50 mM glycine-NaOH pH 9.5 → ultrapure water (Reset + Fill syringe + Run flow rate at 1000 µL/min for 2 min for each solution). |
Cleaning Verification
After running a cleaning protocol, verify that the system is clean before starting the next experiment:
- Baseline stability:Run buffer for 5 minutes and verify that the baseline signal is flat and stable (drift < 0.05 pg/mm² over 5 min). Excessive drift may indicate residual contamination.
- Blank injection: Perform a blank buffer injection and confirm that no signal response is observed. A response during a blank indicates incomplete removal of previous analyte.
- Visual check: Use the surface camera to inspect the chip area for visible residue, particles, or air bubbles trapped in the flow path.
- If verification fails: Repeat the cleaning protocol. If the issue persists after two cleaning cycles, perform an extended cleaning with 0.5% SDS followed by 50 mM glycine-NaOH pH 9.5 and ultrapure water.
Chemical and Material Compatibility
Ensure that all chemicals and materials used with the MACS Matchmaker are compatible to avoid damage and ensure optimal performance. Verify compatibility of all cleaning and regeneration solutions with:
- Flow cell materials (PDMS, PEEK, glass).
- Tubing and seals (PTFE, FFKM, silicone).
- Sensor chips and mologram surfaces.
- External surfaces (especially under BSL-2 cleaning requirements)
Recommended cleaners: ethanol, mild surfactants, or specific biosafety-approved agents. Avoid strong oxidizers unless validated.
Troubleshooting
| Issue | Likely cause | Recommended action |
|---|---|---|
| No fluid flow | Pump not primed, air in line, or blocked tubing | Prime the pump, inspect tubing for kinks or blockages, run maintenance chamber with ultrapure water using the flush fluidics option in the liquid handler |
| Intermittent or unstable flow | Loose MACS sampler tubing or pump slip | Tighten tubing in the MACS sampler, verify pump mounting and tightness and flush pump syringe with ultrapure water. |
| Air bubbles in line | Incomplete priming or permeable/loose connections | Re-prime system with ultrapure water, check connectors |
| High backpressure or flow restriction | Clogged flow chamber or tubing or debris in lines | Stop run, flush with recommended cleaning sequence (SDS → glycine buffer → ultrapure water), inspect/replace flow chamber |
| Contamination or carryover | Insufficient cleaning after complex samples | Run full decontamination: 0.5% SDS → 50 mM glycine-NaOH pH 9.5 → ultrapure water; for long-term storage run 20% ethanol |
| Poor assay performance / low yield | Incorrect buffers, pH drift or degraded reagents | Verify buffer composition and pH, replace expired reagents, rerun control sample |
| Signal Drift | Flow instability, contamination | Equalize flow rates, allow equilibration, clean the MACS sampler and MACS Matchmaker fluidics with cleaning solutions |
| Cannot couple | Coupling not found on Prepare Reader | Escalate through the coupling procedure: prime the chip, retry on Prepare Reader, then try the more detailed coupling on the Instrument Operation page, and finally couple manually via System Control. See Chip Coupling. |
| Weak Focus | Poor coupling or optical misalignment | Check focus alignment and adjust manually |
| High Noise | Poor coupling, poor or no backfilling | Improve coupling by repeating Prepare reader or manual adjustment, use backfilling |
| Unrecognized molograms | Software recognition issue | Verify pattern alignment and coupling, repeat Prepare reader |
| Air Bubbles on the Chip | Bubble present in the MACS sampler syringe or in the samples | Verify that MACS sampler buffer bottle has sufficient volume, prime system 5 times with MQ, if still present, prime system 3x with IPA and 5x with MQ |
| Sample not Injected | Bubble present in the MACS sampler syringe or MACS Sampler pump water empty | Verify that MACS sampler pump bottle has sufficient volume, prime system 5 times with MQ, if still present, prime system 3x with IPA and 5x with MQ |
| Fluid Leakage from the Fluidic Head | Damaged flow chamber, improperly mounted or clogged flow chamber | Remove and inspect the flow chamber for damage, replace if necessary, remount the flow chamber ensuring proper alignment. Clean the spilled area with ultrapure water. |
| Bubbles while sample injected | Not sufficient dead volume | Adjust dead volume in the vials/well plate |
| No response during association phase | Autosampler wash bottle empty or low on MilliQ — an air plug forms in the syringe and buffer tubing, preventing sample aspiration | Refill the wash bottle with fresh MilliQ. Purge the syringe and buffer tubing until all air is removed. Verify proper aspiration before resuming measurements. |
| No response during association phase | Injection valve blocked — wash bottle is filled but sample still cannot be aspirated, syringe plunger meets abnormal resistance | Do not attempt to clear the blockage yourself. Contact Lino Biotech Service Support for assistance. |
Assay-Level Troubleshooting
The following issues are related to assay performance rather than instrument hardware:
| Issue | Possible cause | Recommended action |
|---|---|---|
| High baseline drift | Incomplete passivation or backfilling, temperature fluctuations, or buffer mismatch | Verify passivation or backfilling step was completed. Allow instrument to equilibrate for 15 min. Ensure running buffer and sample buffer are identical. |
| Non-specific binding (control molograms show signal) | Insufficient backfilling, analyte aggregation, or surface contamination | Increase backfilling level to match frontfilling. Centrifuge or filter the analyte. Check for affinity-matched backfilling. |
| Incomplete regeneration | Regeneration conditions too mild, very slow koff, or surface fouling | Try stronger regeneration (e.g., 3 M GdnCl + 125 mM NaOH). Extend regeneration time. For persistent fouling, try 1x trypsin/EDTA. Verify regeneration efficiency by checking baseline return (> 95% is good, < 80% is poor). |
| No binding response despite sample injection | Failed ligand immobilization, inactive analyte, wrong buffer conditions, or solubility issues | Verify immobilization by checking capture level. Test analyte activity with a known positive control. Check buffer pH and ionic strength. |
No Response During Association — Recommended Check Sequence
- Confirm the response is truly absent (not just low).
- Inspect the MilliQ wash bottle level. If low or empty, refill, purge air from the syringe and buffer tubing, and retry.
- If the bottle is sufficiently filled and the problem persists, suspect an injection valve blockage and contact Lino Biotech Service Support.
Prevention: Check the MilliQ wash bottle level before each measurement session to prevent air ingress into the fluidic system.
Contact Support
If you are unable to resolve an issue using the steps above, contact Lino Biotech Support at support@lino-biotech.com. Please include a description of the issue, the steps you have already tried, and any relevant measurement data or screenshots.