⟡ Neuroscience Research Reagents / Neuronal Tracers
Fast Blue
Fast Blue is a fluorescent retrograde neuronal tracer used to identify neurons that project to a defined injection site. It is widely used in academic neuroscience research, especially for long-term survival studies where stable labeling over extended time points is important.
Common applications include neural circuit mapping in rodent central and peripheral nervous system models, followed by fluorescence microscopy, confocal imaging, and neuron counting. Fast Blue is particularly valued when researchers need durable retrograde labeling with limited diffusion from the injection site.
Key Features & Benefits
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Designed for retrograde neuronal tracing: labels neurons that project to the site of injection for pathway mapping and connectivity studies
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Strong choice for long-term studies: commonly selected for long-term survival experiments where signal persistence matters
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High retrograde transport efficiency: supports reliable labeling of projection neurons in CNS and PNS models
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Limited diffusion at the injection site: helps improve spatial specificity and reduce off-target labeling
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Direct fluorescence detection: no enzymatic development required
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Compatible with standard imaging workflows: used with epifluorescence microscopy, confocal microscopy, and neuron counting workflows
Typical Applications
Retrograde neuronal tracing
Identification of neurons projecting to a defined target region.
Neural circuit mapping
Mapping long-range connections in the brain, spinal cord, and peripheral nervous system.
Long-term survival studies
Suitable for experiments with delayed tissue collection and downstream analysis.
Regeneration and injury models
Used in chronic nerve injury, recovery, and plasticity studies.
Academic neuroscience research
Commonly used in university and research institute neuroscience laboratories.
Functional Role
Fast Blue functions as a hydrophilic fluorescent tracer that is taken up at the injection site and transported retrogradely to neuronal cell bodies. This allows researchers to directly visualize projection neurons, quantify labeled populations, and study connectivity with greater precision than indirect approaches alone.
Fluorescence Properties
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Excitation wavelength: 365 nm
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Emission wavelength: 420 nm
Preparation and Use Guidance
Fast Blue is commonly prepared for laboratory animal studies at a concentration of 1.5-2.5% w/v in water. Frequently used protocols describe injecting 5-10 µL of a 2.0% solution into the desired target area.
These conditions are provided as general research guidelines. Protocols may need to be adjusted based on the laboratory animal model, injection site, study design, and downstream analysis methods.
Handling & Storage
- Store in a cool, dry place in the original, tightly sealed container.
- Protect from excessive light exposure to help preserve fluorescence performance.
- Consult the SDS for product-specific handling, preparation, and use guidance.
FAQ
Click a question to expand.
What is Fast Blue used for?
Fast Blue is used for retrograde neuronal tracing to identify neurons that project to a target injection site.
Why do researchers choose Fast Blue?
Researchers often choose Fast Blue for long-term studies because it is associated with durable fluorescent labeling over extended survival times.
What model systems is Fast Blue commonly used in?
It is commonly used in rodent CNS and peripheral nervous system studies, including brain, spinal cord, sensory, and autonomic pathway mapping.
What imaging methods are commonly used after labeling?
Fast Blue labeling is commonly analyzed by fluorescence microscopy, epifluorescence microscopy, confocal microscopy, and neuron counting workflows.
Can Fast Blue be used with other tracers?
Yes. Fast Blue can be used alone or alongside other fluorescent neuronal tracers depending on the experimental design.
