DNA, RNA, and protein quantification for a single or multiple samples

Both Qubit instruments are accurate, sensitive, fast, and simple fluorometers that use the target-specific fluorescent dyes in Qubit Assays to quantify DNA, RNA, or proteins. Choose the model that aligns with typical usage in your lab. The Qubit 4 Fluorometer is designed for low-throughput processing, whereas the Qubit Flex Fluorometer is designed for mid-throughput processing, quantifying up to eight samples at a time, with the flexibility to process other increments. Qubit Flex Fluorometers also support add-on SAE software for 21 CFR Part 11 compliance support.


Which Qubit Fluorometer is best for you?

Both Qubit models work the same way and share common features:

  • Qubit fluorescence quantification technology
  • Simple and fast
  • Onboard Reagent Calculator
  • Fluorometer mode
  • Accurate, specific, and sensitive
  • Requires as little as 1 µL of sample
  • Broad range of assays and applications

The key difference between the models is that the Qubit 4 Fluorometer quantifies one sample at a time, while the Qubit Flex Fluorometer quantifies up to eight samples at a time using Qubit Flex Assay Tube Strips. For more than eight samples, simply insert more tube strips.

 

Tip: For high-throughput quantification, consider using a microplate reader with fluorescence capabilities. The Thermo Scientific Varioskan ALF and Varioskan LUX Multimode Microplate Readers are compatible with Quant-iT assays to quantify the same analytes as Qubit Fluorometers and assays.  For a comparison, see our RNA/DNA Quantification page.

Selection guide

Qubit 4 Fluorometer

 

Qubit Flex Fluorometer

Product summary
Highly accurate, easy-to-use quantification of a single sample of DNA, RNA, or protein
Highly accurate, easy-to-use quantification of a up to eight samples of DNA, RNA, or protein

Detailed comparison table

Feature

Qubit 4 Fluorometer

Qubit Flex Fluorometer

Sample throughput

1 sample in 3 seconds

1–8 samples in 3 seconds

User interface

5.7-inch color touchscreen

8-inch color touchscreen

Onboard calculators

Reagent calculator

Reagent calculator
Assay Range calculator

Molarity calculator

Normalization calculator

System Check

Qubit 4 System Verification Assay Kit

Qubit Flex System Verification Assay Kit

Fluorometer mode

Yes

Yes

Programmable open format

Yes, MyQubit

No

Instrument footprint

13.6 x 25 x 5.5 cm

5.4 x 10 x 2.2 in.

18.6 x 28.2 x 10.3 cm

7.3 x 11.1 x 4.1 in.

Sample data storage

1,000 samples

10,000 samples

Data export

  • Wi-Fi to Thermo Fisher Connect or network drive
  • USB drive
  • Direct to computer via USB cable
  • Wi-Fi to Thermo Fisher Connect or network drive
  • USB drive
  • Direct to computer via Ethernet cable

Light sources

Blue LED (peak ~470 nm)
Red LED (peak ~635 nm)
Blue LED (peak ~460–480 nm)
Red LED (peak ~620–640 nm)

Excitation filters

Blue LED (430–495 nm)
Red LED (600–645 nm)
Blue LED (456–484 nm)
Red LED (612–644 nm)

Emission filters

Green (510–580 nm)
Red (665–720 nm)
Green (513–563 nm)
Far-red (671–693 nm)
21 CFR Part 11 software support Not available Optional add-on SAE software

Qubit 4 Fluorometer

The Invitrogen Qubit 4 Fluorometer accurately and quickly measures the concentration of DNA, RNA, or protein in a single sample. It can also be used to assess RNA integrity and quality. The easy-to-use touchscreen menus make it easy to select and run the assays you need, with results displayed in just a few seconds.


Qubit Flex Fluorometer

The Invitrogen Qubit Flex Fluorometer accurately and quickly measures the concentration of DNA, RNA, or protein in up to eight samples simultaneously. Compared to single-sample microvolume fluorometers, using the Qubit Flex system for multiple samples can reduce your time to data by up to 50%. For 21 CFR Part 11 compliance support, Qubit Flex Fluorometers have an optional add-on SAE software available.