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Nucleic Acid Quantification moderate

Qubit Value Lower Than UV Absorbance

Symptom
Qubit Fluorometer quantification value is significantly lower than UV absorbance (NanoDrop) measurement for the same sample
Common Causes
  1. 1 Sample contaminated with molecules that absorb at 260 nm
  2. 2 Presence of degraded nucleic acids, small fragments, or free nucleotides
  3. 3 Protein contamination affecting UV absorbance reading
  4. 4 NanoDrop detecting contaminants while Qubit measures only intact nucleic acids
  5. 5 Poor sample mixing in assay tube
Solutions
  1. 1 Perform multiple Qubit assays (dsDNA, RNA HS, Protein) on same sample to determine composition
  2. 2 Check assay kit manual for list of potential interfering contaminants
  3. 3 Further dilute or purify sample to reduce contaminant concentration
  4. 4 Mix working solution and sample thoroughly in assay tube
  5. 5 Recognize that Qubit is more specific for intact nucleic acids than UV absorbance
Source: thermofisher.com ↗
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