Qubit™ Protein Quantitation












Qubit™ Protein Quantitation

The Quant-iT™ assays represent the most advanced quantitation systems for DNA, RNA, or protein samples. Molecular Probes state-of-the-art assay reagents deliver high sensitivity and specificity together with a simple, streamlined protocol. All Quant-iT™ kits contain prepared buffers and prediluted standards — just dilute the dye in the provided buffer, add your sample, and read!

Selection Guide for the Quant-iT™ Assay Kits


  • Cat # Kit Name Target Useful Range* Ex/Em †
    Q33120 Quant-iT™ DNA Assay Kit, High Sensitivity dsDNA 0.2–100 ng 502/523
    Q33130 Quant-iT™ DNA Assay Kit, Broad Range dsDNA 2–1000 ng 510/527
    Q33140 Quant-iT™ RNA Assay Kit RNA 5–100 ng 644/673
    Q33210 Quant-iT™ Protein Assay Kit Protein 0.25–5 µg 470/570

    * A 1–20 µL sample volume in a 96-well microplate assay.
    † Excitation (Ex) and fluorescence emission (Em) maxima of the Quant-iT™ reagents, in nm.

Four Assays Cover Your Quantitation Needs In Molecular Biology and Biochemistry

Each Quant-iT™ Kit contains:

  • A state-of-the-art reagent for sensitive and selective quantitation of your sample
  • Prediluted standards for an accurate standard curve every time
  • Ready-to-use buffer
  • Easy-to-follow instructions
  • Sufficient reagents to perform 1000 assays, based on the 96-well microplate format

 

 Figure 1.

Quant-iT™ DNA Assay Kit, High Sensitivity

High-sensitivity DNA quantitation
(for sample concentrations from 10 pg/µL to 100 ng/µL)

  • Quantitates DNA from 0.2 ng to 100 ng
  • Accurate in the presence of an equal mass of RNA
  • Signal is unaffected by many common contaminants, including free nucleotides, salts, solvents, and proteins
  • Fluorescence is detected using standard fluorescein filters
  • Great for quantitating PCR products, viral DNA, DNA fragments for subcloning, and other applications involving small amounts of DNA

 

Figure 2. The Quant-iT™ High-Sensitivity DNA Assay Kit has a linear detection range of 0.2–100 ng and is selective for dsDNA, even in the presence of an equal mass of RNA. The x-axis gives the mass of nucleic acid at a given point when DNA or RNA is assayed alone. In the 1:1 mixture, the total mass of nucleic acid at a given point is double what is stated on the x-axis.

Quant-iT™ DNA Assay Kit, Broad Range

Fast quantitations of concentrated DNA solutions
(for sample concentrations from 100 pg/µL to 1000 ng/µL)

  • Quantitates DNA from 2 ng to 1000 ng
  • Accurate in the presence of an equal mass of RNA
  • Signal is unaffected by many common contaminants, including free nucleotides, salts, solvents, and proteins
  • Fluorescence is detected using standard fluorescein filters
  • Eliminates the need to dilute concentrated samples, such as genomic DNA and miniprep DNA, prior to high-throughput procedures
  • View our Quant-iT™ DNA Assay Kit, Broad Range

 

Figure 3. The Quant-iT™ Broad-Range DNA Assay Kit has a linear detection range of 2–1000 ng and is selective for dsDNA, even in the presence of an equal mass of RNA. The x-axis gives the mass of nucleic acid at a given point when DNA or RNA is assayed alone. In the 1:1 mixture, the total mass of nucleic acid at a given point is double what is stated on the x-axis.

Quant-iT™ RNA Assay kit

The first homogeneous assay ever developed for quantitation of RNA in the presence of DNA
(for sample concentrations from 250 pg/µL to 100 ng/µL)

  • Quantitates RNA from 5 ng to 100 ng
  • Accurate in the presence of an equal mass of DNA
  • Signal is unaffected by many common contaminants, including free nucleotides, salts, solvents, and proteins
  • Ideal for measuring samples for microarray, RT-PCR, and Northern blot procedures




Figure 4. The Quant-iT™ RNA Assay Kit has a linear detection range of 5–100 ng and is selective for RNA, even in the presence of an equal mass of DNA. The x-axis gives the mass of nucleic acid at a given point when DNA or RNA is assayed alone. In the 1:1 mixture, the total mass of nucleic acid at a given point is double what is stated on the x-axis.

Quan-iT™ Protein Assay kit

This fluorescence-based protein assay is easier and more sensitive than standard absorbance-based assays
(for sample concentrations from 12.5 µg/mL to 5 mg/mL)

  • Quantitates proteins from 0.25 µg to 5 µg
  • Signal is unaffected by many common contaminants*, including DTT, -mercaptoethanol, amino acids, and DNA
  • Little protein-to-protein difference in signal
  • Signal is stable for 3 hours
  • not compatible with detergents

 

Figure 5. The Quant-iT™ Protein Assay Kit has a detection range of 0.25–5 µg. This graph shows the signal generated from nine different proteins over the stated detection range. The protein-to-protein variability at the 3 µg point for all nine proteins assayed is 12%.