Hydrazides & biocytins for neuron staining

These low molecular weight polar tracers cross gap junctions and follow neuronal projections. Offered in a range of fluorescent colors, they can be multiplexed with other probes, and biocytins easily accept secondary detection for effective signal amplification.


Select hydrazides & biocytins for neuron staining

Hydrazides & Biocytins for Neuron Staining

  • Load by microinjection or iontophoresis
  • Fixable and photostable
  • Able to cross gap junctions
  • Use direct detection or signal amplification

With low molecular weights (<1,000 Da) and bright fluorescent signals, these cell-impermeant polar tracers can be employed to trace neuronal projections and investigate gap junctions. They are fixable and photostable and are offered in multiple colors for multiplexing with other fluorescent probes. Biocytins can also be detected using fluorescent streptavidin conjugates for signal amplification.

Because they cross gap junctions, biocytins and hydrazides are often used to investigate neuronal communication in conjunction with labeled dextrans, which are retained within the cell.

 Biocytins and hydrazides
Confocal image stack of a 10,000 MW Calcium Green dextran–labeled climbing fiber in a sagittal cerebellar slice, showing incoming axon and terminal arborization (in yellow). The Purkinje cell innervated by this fiber was labeled with Alexa Fluor® 568 hydrazide.

Selection Guides for Hydrazides and Biocytins

Properties

ReadoutDirect fluorescence imaging of cells
Tissue sectionsYes
In vivo neuronsYes
Fixed tissue sectionsNo
Cultured cellsYes
Cell loadingMicroinjection, iontophoresis
Staining modeEndogenous
Best forSingle cells
Fixable5 stars
TransportBidirectional
Photobleaching resistance5 stars
Synaptic transferNo
Gap junction transferYes
BibliographyCitations

 

Selection Guide

 
Carrier
Standard filter set(s)
Fluorophore
Ex/Em (nm)
Quantity
Cat. No.
Alexa Fluor® 350 HydrazideHydrazide, sodium saltDAPIAlexa Fluor® 350346/4425 mgA10439
Alexa Fluor® 488 HydrazideFITCAlexa Fluor® 488495/5195 mgA10436
Alexa Fluor® 568 HydrazideRhodamineAlexa Fluor® 568578/6035 mgA10437
Alexa Fluor® 594 HydrazideTexas Red®Alexa Fluor® 594590/6175 mgA10438
Alexa Fluor® 555 HydrazideHydrazide, Tris(triethylammonium)
salt
TRITCAlexa Fluor® 555555/5651 mgA20501MP
Alexa Fluor® 633 HydrazideTexas Red®Alexa Fluor® 633632/6471 mgA30634
Alexa Fluor® 647 HydrazideCy®5Alexa Fluor® 647650/6681 mgA20502

Properties

Readout
Direct fluorescence imaging of cells; biocytins easily accept secondary detection to amplify weak signals
Tissue sectionsYes
In vivo neuronsYes
Fixed tissue sectionsNo
Cultured cellsYes
Cell loadingMicroinjection, iontophoresis
Staining modeEndogenous
Best forSingle cells
Fixable5 stars
TransportBidirectional
Photobleaching resistance5 stars
Synaptic transferNo
Gap junction transferYes
BibliographyCitations

 

Selection Guide

  Carrier
Standard filter set(s)
Fluorophore
Ex/Em (nm)
Quantity
Cat. No.
Alexa Fluor® 488 Biocytin

Biocytin,
sodium salt

FITCAlexa Fluor® 488495/519250 μgA12924
Alexa Fluor® 546 BiocytinTRITCAlexa Fluor® 546556/573250 μgA12923
Alexa Fluor® 594 BiocytinTexas Red®Alexa Fluor® 594590/617250 μgA12922