Welcome to SETA BioMedicals

SETA BioMedicals is the exclusive producer of squaraine rotaxanes, the world's brightest, chemically robust, and photostable fluorescent dyes for biomedical applications.

SETA BioMedicals develops, produces, commercializes, sells, and licenses proprietary fluorescent detection reagents, including dyes, probes, labels, tags, tandems, conjugates, and standards, for use with the latest fluorescence techniques in biology, medical diagnostics, biomedical and pharmaceutical research, environmental monitoring, and food control. These reagents include rotaxanes—specifically, squaraine rotaxanes—as well as advanced cyanines and squaraine dyes of the SeTau, Seta, and Square series.

These dyes cover a wide spectral range from the UV to the near-infrared (NIR) region. Available in both reactive and non-reactive forms, they can be attached to various types of carrier molecules. They also show brighter fluorescence, higher chemical stability, and higher photostability compared to Cy dyes, Alexa dyes, ATTO dyes, IRDyes, LiCor dyes, Dy dyes, BrightDyes, BODIPY dyes, and other commercially available alternatives.

In addition, they have longer lifetimes (FLTs) up to 32 ns in aqueous buffer systems. Donor-acceptor pairs and true dark quenchers (SQ dyes)—superior alternatives to Black Hole Quenchers (BHQ), QSY quenchers, Iowa Black quenchers, and Dabcyl—are also available for FRET-based applications.

SETA BioMedicals also provides custom development, custom synthesis, conjugation, and consulting services.

These detection reagents and services can be ordered over the phone and WhatsApp at (217) 417 2160, via e-mail at orders@setabiomedicals.com, or via online shopping. Orders are delivered within 24 hours in the continental USA or CA and within days worldwide.

TECHNOLOGY HIGHLIGHTS

Squaraine Rotaxanes - Simply the Best!
Conventional fluorescent dyes, particularly those in the red and near-IR spectral region, exhibit lower chemical and photochemical stability, brightness, and fluorescence lifetimes.

Our proprietary squaraine rotaxane dyes are based on a squaraine dye fluorophore, where the central squaraine moiety is protected by a macrocyclic ring, which helps to improve the properties of the final dye (see image above).

This innovative technology has enabled the development of highly bright, exceptionally photostable, and chemically stable dyes, probes, labels, tandem conjugates, and fluorescent standards for the long-wavelength region. In addition, squaraine rotaxanes exhibit longer fluorescence lifetimes (FLTs) compared to other dyes in the same long-wavelength spectral region.

Exceptional photostability of squaraine rotaxanes compared to conventional long-wavelength dyes

The long-wavelength squaraine rotaxanes (SeTau-665, SeTau-660 and SeTau-647) have longer fluorescence lifetimes (FLTs) compared to Atto 647, Alexa 647 or Cy5

The long-wavelength squaraine rotaxanes (e.g. SeTau 647) also exhibit higher brightness compared to Atto 647, Alexa 647 or Cy5.

Squaraine rotaxanes are available as imaging probes and in reactive forms with NHS-ester, maleimide, azide, and DBCO modifications for a wide range of applications.

Experience the performance of squaraine rotaxane dyes firsthand - we guarantee that you will not be disappointed!
Click Chemistry Reagents
Azides and proprietary DBCO derivatives of long-lifetime and 2P-imaging dyes with 2PACS of several thousand GM for Cu-catalyzed and Cu-free click chemistry reactions
Phycobiliprotein Tandem Conjugates
Bright and photostable tandem-conjugates of APC, PE, and PerCP with Seta dyes for flow cytometry and immuno-fluorescence applications.

Blood cells stained with CD3-Seta-APC-780
Lifetime and Intensity-Based Calibration Standards
Fluorescence standards that are utilized in the calibration and validation of fluorescence instruments and luminescence readers as fluorescence reference materials. The standard kits offered by SETA BioMedicals are ready and easy to use!
Fluorescence Lifetime Labels
Fluorescent labels with lifetimes (FLTs) of 0.5 to 32 ns in aqueous buffer systems for fluorescence lifetime- and polarization-based applications.

The dyes of our SeTau blue series (SeTau 380, SeTau 405 and SeTau 425) exhibit much longer fluorescence lifetimes (FLTs) in aqueous systems compared to any other dye (e,g, Atto 386H or Alexa 405)

Fluorescence lifetime (FLT) immunoassay using an environment-sensitive lifetime label (Seta 633), eliminating the need for donor-acceptor pairs required for conventional FRET-based assays
Viscosity-Sensitive Probes and Labels
Large Stokes' shift fluorescent molecular rotors with high sensitivity and a large dynamic range in lifetime and intensity mode. They are available in reactive (NHS-ester and maleimide) and non-reactive formats.
Exeptional Dyes for 2-Photon Microscopy
Fluorescent probes and labels with exceptionally high 2-photon action cross sections (2PACS) close to 10,000 GM based on squaraines and squaraine rotaxanes.

Comparison of the two-photon action cross sections (2-PACS) of red-emitting Seta and SeTau dyes to Alexa 647 for excitation at 900 nm. The 2-PACS values are presented on a logarithmic scale.

APPLICATIONS

Applications of Squaraine Rotaxanes

Exceptionally photostable, chemically stable dyes, and extremely bright probes, labels, tandem conjugates, and fluorescent standards have been developed by SETA BioMedicals based on squaraine rotaxanes.

Due to their extreme resistance to oxidizers, squaraine rotaxanes are advantageous for use in a wide range of biomedical, pharmaceutical, and environmental sensing applications, including:
- Oxidative stress detection assays
- Oxidative damage assays
- Live-cell imaging under oxidative conditions
- Super-resolution microscopy (STORM/STED)
- Immunofluorescence in oxidizing environments
- Photo-oxidation, photodynamic therapy (PDT), and sonodynamic therapy (SDT) studies
- Monitoring of drug delivery and oxidation-triggered drug release
- Flow cytometry
- Detection of oxidative pollutants in water, air, and soil.
DNA and Protein Microarrays

Our highly fluorescent squaraine rotaxanes exhibit excellent chemical stability in particular against oxidative reagents e.g. peroxides or ozone and therefore are outstanding detection reagents for use in DNA and protein microarrays. Importantly our customers found that the fluorescence signals of cyanine dyes such as Cy5, Atto and Alexa dyes are strongly dependent on the concentration of ozone during array washing - see our Microarray Signal Stability Comparison and below.

Images of the protein microarray scans of a SeTau-647 rotaxane dye-labeled-neutravidin attached to an immobilized, biotinylated antibody at time = 0 and after 6 hours (left) and an Alexa-647-labeled neutravidin at time = 0 and after 2 hours (right).
Microarray Imaging

Below is a comparison of our Seta-555 and SeTau-647 dyes with other dyes commonly used in such microarrays. These dyes are ideal for both, one- and two-color microarray measurements and they have much higher ozone stability as compared to other dyes. Try and experience the difference yourself!
Single Molecule Applications

In a comparative study of common dyes used for single molecule application — including TRITC, Rhodamine 110, DY 647, Cy3, Cy5, Dy547, Alexa 488, Atto 488, Atto 594, and Atto 647N — the squaraine rotaxane dye SeTau-647 exhibited the best photobleaching performance, with an exponential lifetime of 105.8 seconds, approximately twice as long as the second-best dye, Atto-647N [Nature Chem Biol, 2018, 14, 497].

Single-fluorescence-moleculecular-imaging photobleaching lifetimes in the presence of 2% and 21% O₂. Dyes were located on the outer surface of a living T24 epithelial cell
Imaging Technologies

Next generation labels for proteins, oligonucleotides and other biomolecules with exceptional brightness and photostability.

Mouse egg cell stained with
Square-655 and Square-460 Mouse egg cell stained with
Square-670-Carboxy
Superresolution Microscopy

Seta and SeTau dyes are a class of extremely bright and photostable dyes for fluorescence imaging and are well suited for STED and STORM applications.

STED image of HeLa-M cell nuclei labeled with primary mAB414 antibody and a secondary antibody labeled with SeTau-647.
2-Photon Microscopy

Squaraine and squaraine-rotaxanes have 10 – 50-times higher 2-photon cross-sections compared to conventional cyanine dyes in the order of several thousand GM.

2-Photon image of a neuron filled with a squaraine rotaxane-labeled peptide


Mouse egg cell stained with Square-655 and Square-460	Mouse egg cell stained with Square-670-Carboxy