ATTO 565, Orange Emission

ATTO® 565 is a premium orange-red fluorescent dye designed for demanding fluorescence imaging, molecular diagnostics, and analytical applications. Its excellent brightness, high fluorescence quantum yield, and exceptional resistance to photobleaching make it an ideal fluorophore for quantitative fluorescence measurements and long-term imaging experiments.

ATTO® 565 is commonly conjugated to DNA, RNA, PNA, LNA, siRNA, antisense oligonucleotides (ASOs), aptamers, peptides, proteins, and other amino-modified biomolecules using NHS ester chemistry, producing a stable amide bond with primary amino groups. Alternative labeling strategies, including click chemistry and other orthogonal conjugation methods, may also be used depending on the experimental design.The dye exhibits excitation and emission maxima of approximately 563 nm and 592 nm, respectively, making it highly compatible with 561 nm laser systems commonly used on confocal microscopes, fluorescence microscopes, flow cytometers, and imaging instruments. ATTO® 565 provides excellent spectral separation from green, far-red, and near-infrared fluorophores, making it particularly valuable for multicolor fluorescence imaging and multiplex detection.

Features:

• Replacement dye for Cy3.5, ROX, PET
• Excitation range: 545-575 nm
• High fluorescence yield
• High thermal and photo-stability
• Cationic dye
• Supplied as mxiture of two isoemer (single isomer available)

ATTO 565 dye can be incorporated at any position within an Oligonucleotide. A primary amine modified oligonucleotide is used to covalently attach with dye via NHS conjugation chemistry; other cross-linking chemistries are also available depending on particular project specifications. Dual HPLC purification is used to remove failure sequences during first HPLC purification,  after labeling, the second HPLC is performed to remove unlabeled oligonucleotides and excessive dye in order to obtain a full length labeled oligonucleotide.

Bio-Synthesis offers custom ATTO® 565-labeled oligonucleotides for DNA, RNA, PNA, LNA, siRNA, ASOs, molecular beacons, aptamers, and other synthetic nucleic acids. ATTO® 565 can be incorporated at the 5′ end, 3′ end, or internal amino-modified positions, and may be combined with numerous additional modifications including quenchers, biotin, thiol modifiers, amino modifiers, PEG linkers, click chemistry handles, GalNAc, cholesterol, peptide conjugates, lipid conjugates, and other custom chemistries.

Each labeled oligonucleotide is synthesized under stringent quality standards and is available with optional HPLC purification, together with analytical characterization by HPLC, LC-MS, MALDI-TOF, UV-Vis spectroscopy, and fluorescence analysis to verify labeling efficiency, sequence identity, and product purity.

Property	Typical Value
Fluorophore	ATTO® 565
Fluorescence Color	Orange-Red
Typical Reactive Group	NHS ester (or other conjugation formats)
Target Functional Group	Primary amino groups
Bond Formed	Stable amide bond
Excitation Maximum	563 nm
Emission Maximum	592 nm
Laser Compatibility	561 nm DPSS laser
Filter Compatibility	TRITC / Cy3 filter sets
Compatible Oligos	DNA, RNA, PNA, LNA, siRNA, ASO, Aptamers
Typical Labeling Sites	5′ end, 3′ end, internal amino modifiers

Trademark Notice: ATTO® is a registered trademark of ATTO-TEC GmbH. Bio-Synthesis provides custom conjugation services using customer-specified or commercially available fluorescent dyes and is not affiliated with or endorsed by ATTO-TEC GmbH.