Invitrogen™ ActinRed™ 555 ReadyProbes™ Reagent

Invitrogen™ ReadyProbes™ F-Actin Phalloidin Conjugates are ready-to-use fluorescent probes designed for rapid, high-affinity staining of filamentous actin (F-actin) in fixed and permeabilized cells or tissues. These reagents combine the specificity of phalloidin with bright, photostable fluorescent dyes for superior cytoskeletal visualization.

Available in two optimized color formats:

• ActinGreen™ 488 (R37110) – Alexa Fluor™ 488 conjugate
• ActinRed™ 555 (R37112) – Tetramethylrhodamine (TRITC) conjugate

Both reagents are supplied in convenient dropper bottles, eliminating dilution steps and simplifying workflow.

Key Features

• High-affinity, selective F-actin staining
• Superior specificity compared to antibody-based actin labeling
• Low non-specific binding
• Ready-to-use liquid format
• Stable at room temperature (≤25°C)
• Compatible with standard GFP/FITC and RFP/TRITC filter sets
• Ideal for imaging and high-content applications

Fluorescence Properties

Applications

• Fluorescence microscopy (IF, ICC, IHC)
• Confocal microscopy
• High-content screening & imaging
• Flow cytometry
• Cytoskeleton visualization
• Morphology and cell structure studies

How It Works

Phalloidin is a bicyclic peptide that binds selectively and tightly to filamentous actin (F-actin). Fluorescently labeled phalloidin provides:

• Consistent binding across species (plants and animals)
• More uniform labeling than antibodies
• Reduced background staining

Suggested Protocol

1. Fix and permeabilize cells or tissue.
2. Add 2 drops per mL of medium or buffer.
3. Incubate for 15–30 minutes.
4. Wash and image.

Optimization may be performed by adjusting drop volume depending on cell type or staining intensity requirements.

Counterstains such as DAPI or NucBlue™ ReadyProbes™ can be used for nuclear visualization.

Technical Specifications

Compatible Equipment

• Confocal microscopes
• Fluorescence microscopes
• Flow cytometers
• EVOS™ and Floid™ imaging systems

Invitrogen™ ReadyProbes™ F-Actin Phalloidin Conjugates provide a fast, reliable, and high-performance solution for cytoskeletal imaging. Their ready-to-use format reduces preparation time while delivering bright, photostable staining of F-actin with minimal background.