Product manual
Product use, preparation, operating conditions and storage.
Nucleic-acid stains and labeling reagentsDetection probe
TOTO-3 1mM
Cat. No.QH-60-6023
Fluorescence enhancement on nucleic-acid binding for isolated nucleic-acid imaging and detection in suitable samples.
Packs & quotePrepare isolated nucleic acids or complexes
Compare dye-to-nucleic-acid ratios
Image and assess sample condition
Excitation642 nm
Emission661 nm
TargetAccessible DNA and RNA
Preparation and storage
- Preparation
- Soluble in water or DMSO
- Storage
- Store at -20°C, protect from light
Nucleic-acid binding and detection
Dimeric cyanine dyes brighten on nucleic-acid binding and generally do not enter intact cells readily. Binding can alter nucleic-acid physical properties; control the dye:nucleic-acid ratio rather than assuming DNA remains unchanged.
Nucleic-acid imaging
Image suitable DNA or nucleic-acid complexes after comparing sample state and required function before and after staining.
Specifications
Product information
- Product name
- TOTO-3 1mM
- Cat. No.
- QH-60-6023
- Product form
- Nucleic-acid stains and labeling reagents
- Target
- Accessible DNA and RNA
- Pack sizes
- 100 μl
Preparation and properties
- Excitation wavelength
- 642 nm
- Emission wavelength
- 661 nm
- CAS
- 166196-17-4
- Molar extinction coefficient
- 154,000 M⁻¹ cm⁻¹
- Quantum yield
- 0.06
- Preparation and sample
- Soluble in water or DMSO
- Storage
- Store at -20°C, protect from light
Spectral information and detection
Product parameters
Use parameters for the exact catalog number when preparing reagents, setting reagent input or calculating results. Request a lot-specific CoA for test results.
Protocol
Check formulation concentration
Confirm whether the pack is solid, an mM stock or a fold-concentrated solution. Do not reconstitute an existing solution as a solid or interchange molar and fold-concentration units.
Nucleic-acid sample and binding ratio
Check nucleic-acid type, length, concentration and buffer. Calculate dilution from this product’s 1 mM stock and record the final solvent fraction. Validate permeability separately for cellular use rather than assuming access to intact cells.
Prepare isolated nucleic acids or complexes
Confirm nucleic-acid integrity and retain unstained material and a dye blank. Isolated nucleic acid requires no cellular fixation; validate accessibility for cells or complexes.
Compare dye-to-nucleic-acid ratios
Match nucleic-acid input, buffer and solvent fraction while comparing dye amount and binding time using this product’s guidance. Record nucleic-acid amount and its measurement basis; equal masses of different-length nucleic acids are not equal molecule counts.
Image and assess sample condition
Compare bound signal and free-dye background under matched, unsaturated acquisition settings, while checking the state and required function of stained nucleic acids or complexes. Confirm composition independently rather than treating total fluorescence as covalent-labeling efficiency.
Request product documentation
Select a document and enter your phone and email. Include the lot number for a CoA.
TOTO-3 1mMQH-60-6023
Spectra and measurement conditions
Spectra, measurement conditions and detection settings for the exact catalog number.
Certificate of analysis (CoA)
Lot-specific test results. Include the lot number from the vial.
Safety data sheet (SDS)
Handling, storage and emergency response information.
Quality and lot information
Unstained control
Establish sample autofluorescence and detection background.
Handling and dose controls
Compare doses and processing steps to assess changes caused by dye, sample loss or exposure.
References
Nucleic-acid stain binding and membrane permeability
Thermo Fisher Scientific · Molecular Probes Handbook · Section 8.1
Distinguishes DNA preference, membrane permeability and suitable readouts among nucleic-acid stains.
Frequently asked questions
Does strong fluorescence establish covalent labeling?
This dye brightens on nucleic-acid binding, which does not establish covalent NHS or click coupling. For a covalent probe, choose a reagent matched to a modified handle.
Can stained DNA be assumed to retain its physical properties?
Binding can change nucleic-acid properties. Control the dye:nucleic-acid ratio and compare integrity and downstream function with unstained material, particularly in imaging or complex studies.
Can YOYO-1 and TOTO-3 share a detection channel?
They occupy different detection bands. Configure illumination, filters and detectors from the selected catalog number’s excitation/emission data and validate background and signal separately.