ProLong® Gold reagent is a liquid mountant applied directly to fluorescently labeled cell or tissue samples on microscope slides. ProLong® Gold reagent contains chemical components designed to protect fluorescent dyes from fading (photobleaching) during fluorescence microscopy experiments, and it delivers this protection without significantly quenching the initial fluorescence signal (Ref 1). ProLong® Gold reagent is a curing mountant that forms a near perfect optical path (1.47 RI) and allows longer-term storage of the sample. It comes ready to use (no mixing required)—just apply a drop to the sample, add a coverslip, cure, and image. ProLong® Gold reagent is available with or without DAPI nuclear stain in two packaging formats: one 10 mL vial or five 2 mL vials.

Key Attributes

• Protects dyes from fading during imaging
• Ready-to-use liquid that cures for longer-term storage
• Mounted samples are stable for months
• Maintains fluorescence signal—little to no quenching
• Ideal for Alexa Fluor® and Cy® dyes—compared to competitor products, improved performance is especially noted with red dyes (Ref 2)

Get Photobleaching Protection Without Quenching Many mountants can destroy initial fluorescence signal strength by up to 80%. To create the Molecular Probes® Gold series of mountants, our scientists developed a formula of chemical additives that minimize this initial signal quenching for the broadest range of colors and dyes. See (Ref 2,3) for information on the level of photobleaching protection achieved for various dyes.

Stable Signals During Imaging and for Longer-Term Storage While epoxy-based mountants used in our FluoCells® series of prepared cells can be stable for years and afford the highest level of antifade protection, they are difficult to use, requiring a series of steps in organic solvents prior to mounting. ProLong® Gold is the next best option for archiving samples. And it is the best option for preserving signal strength during prolonged imaging sessions, such as repeated scanning under confocal laser scanning illumination. It’s easy to use: just air-dry your stained samples to remove excess water and mount (Ref 3). For immediate viewing of the sample, choose our noncuring mountant, SlowFade® Gold reagent. For photobleaching protection with Qdot® nanocrystals, we offer Qmount® Qdot® mounting medium.

Achieve Excellent Refractive Index Matching Without Acrylic Resins For modern high-resolution imaging applications, refractive index matching is critical. ProLong® Gold reagent will cure to an Rf of 1.47 (Ref 4). Additionally, the curing property means you can avoid messy acrylic resins (i.e., finger nail polish), which can damage or ruin modern microscope objectives if it comes into contact with them.

Proven Performance Backed by years of use, the Gold series of mountants have been cited in over 2,000 peer-reviewed articles (as tabulated using Highwire press).
For Research Use Only.  Not intended for any animal or human therapeutic or diagnostic use.