Clogged column |
Insufficient sample disruption or homogenization |
- Increase time of sample digestion or homogenization
- Centrifuge sample after Proteinase K digestion or homogenization to pellet debris and use only supernatant for next steps
- Use larger volume of DNA/RNA Protection Reagent (NEB #T2011) and/or RNA Lysis Buffer (NEB #T2012) for sample disruption and homogenization. See sample specific protocols online or in the Product Manual.
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Too much sample |
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Low yield |
Incomplete elution |
- After addition of Nuclease-free Water (NEB #B1500) to column matrix, incubate 5-10 min at room temperature and then centrifuge to elute
- Perform a second elution (note: this will dilute sample)
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Sample is degraded |
- Store input sample at -80°C prior to use
- Use Monarch DNA/RNA Protection Reagent (NEB #T2011) to maintain RNA integrity during storage
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Insufficient disruption or homogenization |
- Increase time of sample digestion or homogenization
- Centrifuge sample after Proteinase K digestion or homogenization to pellet debris and use only supernatant for next steps
- Use larger volume of DNA/RNA Reagent (NEB #T2011) and/or RNA Lysis Buffer (NEB #T2012) for sample disruption and homogenization. See sample specific protocols online or in the Product Manual.
- For Proteinase K treated samples, doubling Proteinase K (from 5% to 10%) may lead to an increase in RNA yield
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Too much sample |
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RNA degradation |
Starting material not handled/stored properly |
- Store input sample at -80°C prior to use. Degradation of RNA may occur if sample is not flash frozen or protected by a preservation reagent. Use Monarch DNA/RNA Protection Reagent (NEB #T2011) to maintain RNA integrity during storage.
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Deviation from the stated protocol may expose RNA to unwanted RNase activities |
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RNase contamination of eluted materials or kit buffers may have occurred |
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Low OD ratios |
Low A260/280 values indicate residual protein in
the purified sample |
- Ensure the Proteinase K step was utilized for the recommended time. Ensure samples have no debris prior to addition of ethanol and loading onto RNA Purification Column.
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Low A260/230 values indicate residual guanidine salts have been carried over during elution |
- Ensure wash steps are carried out prior to eluting sample. Use care to ensure the tip of the column does not contact the flow-through after the final wash. If unsure, please repeat centrifugation. When reusing collection tubes, blot rim of tube on a Kimwipe prior to reattachment to the column to remove any residual wash buffer.
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DNA contamination |
Genomic DNA not removed by column |
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Too much sample |
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Low performance of RNA in downstream steps |
Salt and/or ethanol carryover has occurred |
- Use care to ensure the tip of the RNA Purification Column does not contact the flow-through after the final wash. If unsure, please repeat centrifugation
- Be sure to spin the RNA Purification Column for 2 minutes following the final wash with RNA Wash Buffer
- When reusing collection tubes, blot rim of tube on a Kimwipe prior to reattachment to the column to remove any residual wash buffer
- Add additional wash step and/or extend spin time for final wash
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Unusual Spectrophotometric readings |
RNA concentration is too low for spectrophotometric analysis |
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Silica fines in eluate |
- Re-spin eluted samples and pipet aliquot from the top of the liquid to ensure the A260/230 is unaffected by possible
elution of silica particles
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