Alexa Fluor™ Plus Amine-Reactive Dyes

Invitrogen Alexa Fluor Plus amine-reactive dyes represent a chemically optimized fluorescent labeling solution designed to address critical limitations of traditional fluorescent dyes in protein target identification applications. These spectrally diverse fluorophores have been engineered to significantly reduce nonspecific staining while delivering enhanced signal-to-noise ratios, enabling precise detection of low-abundance targets in rare or precious biological samples.

Unlike conventional fluorescent dyes that exhibit problematic cross-reactivity and elevated background staining, the Alexa Fluor Plus dye series provides researchers with an accessible method for generating bright, reliable fluorophore conjugates that yield high-quality imaging data with improved interpretability. The dyes are specifically optimized for compatibility with Zeba Dye and Biotin Removal Columns (Cat. No. A44298), facilitating streamlined purification workflows in fluorescent labeling protocols.

Features of Alexa Fluor Plus amine-reactive dyes include:

• Multiplexing optimization—specifically engineered for superior performance in multiplexing experiments, enabling simultaneous detection and analysis of multiple targets within a single assay
• Low-abundance target detection—designed with enhanced sensitivity capabilities to effectively detect and visualize low-abundance targets in rare or precious sample materials where sample conservation is critical
• Superior optical performance—delivers enhanced brightness characteristics that significantly improve signal detection and target visualization compared to conventional labeling reagents
• Enhanced photostability—exhibits improved resistance to photobleaching, helping ensure consistent signal intensity throughout extended imaging sessions and repeated exposures
• Optimized signal-to-noise ratio—provides higher signal-to-noise ratio performance, resulting in clearer target discrimination and reduced background interference
• Versatile amine-reactive chemistry—features convenient amine-reactive functional groups that enable efficient conjugation to a broad range of biomolecules including antibodies, proteins, peptides, and oligonucleotides
• Broad application compatibility—suitable for labeling diverse molecular targets, making it adaptable to various experimental protocols and research applications

Enhanced optical performance through advanced fluorophore design

Alexa Fluor Plus reactive dyes represent a significant advancement in fluorescent labeling technology, delivering superior brightness and photostability compared to conventional fluorescent dyes. These enhanced optical properties translate directly to improved image quality, enabling researchers to visualize greater detail within their biological samples. The increased photostability is particularly valuable for extended imaging sessions and time-lapse experiments, where photobleaching of traditional fluorophores can compromise data quality and experimental outcomes.

Optimized small molecule architecture for versatile protein labeling

The Alexa Fluor Plus dyes are engineered as small, organic fluorophores that maintain the structural integrity and biological activity of target proteins while providing exceptional fluorescent signal. These fluorophores are supplied in an amine-reactive format, allowing for straightforward conjugation to primary amines present in proteins, including lysine residues and N-terminal amino groups. This reactive chemistry ensures efficient and stable covalent attachment to the protein of interest while minimizing potential interference with protein function.

Streamlined labeling protocol for consistent results

The recommended labeling procedure involves dissolving the reactive dye in dimethyl sulfoxide (DMSO) to create a working solution, followed by incubation with the target protein under appropriate reaction conditions. Following the labeling reaction, removal of unbound dye is critical for achieving optimal signal-to-noise ratios and preventing background fluorescence. This purification step can be efficiently accomplished using specialized purification systems such as Pierce Zeba Dye and Biotin Removal columns and filter plates, which provide rapid and effective separation of labeled protein from excess unreacted dye.

Comprehensive product portfolio for diverse research applications

Beyond the reactive dye format, Alexa Fluor Plus dyes are available in multiple convenient formats to accommodate various experimental needs. Researchers can access these advanced fluorophores as pre-conjugated primary and secondary antibody conjugates, eliminating the need for custom labeling procedures in immunofluorescence applications. Additionally, ReadyLabel antibody labeling kits provide a complete solution for researchers who prefer to perform their own antibody conjugations, offering all necessary reagents and protocols in a single, optimized package.