Support & Resources



Reagents & Accessories for
DNA/RNA Gel Electrophoresis

The most sensitive red fluorescent DNA gel stain, proven safer than EtBr.
A safer and more sensitive alternative to SYBR® Green I green fluorescent gel stains.
Similar to our classic GelRed® stain, but made to stain DNA in PAGE gels with high sensitivity.
A novel visible blue DNA gel stain, extremely sensitive and great for cutting out bands for cloning.
Much greater sensitivity for RNA than EtBr, and allows convenient denaturing, loading, and tracking in a single step.
Obtain results up to 3X faster with this low ionic strength buffer for higher voltage electrophoresis.
Featuring high-quality and low cost forms of Oxazole Gold (SYBR® Gold) and Thiazole Green (SYBR® Green I).
Novel laser diode-based illumination for excellent performance with green and red fluorescent dyes.


How Safe is Your Gel Stain?

A number of ethidium bromide (EtBr) alternatives are marketed as being safe. In fact, many so-called “safe” gel stains contain dyes that are well known to bind DNA in living cells, with cytotoxic effects. GelRed® and GelGreen® are highly sensitive gel stains designed to be nontoxic and nonmutagenic by virtue of being cell membrane impermeable, so they cannot enter living cells. Download our white paper to learn more.

GelRed® and GelGreen®

Safer alternatives to EtBr, SYBR® Safe, and others

EtBr has been the predominant dye used for nucleic acid staining for decades because of its low price and generally sufficient sensitivity. However, EtBr is a highly mutagenic material. The safety hazard and costs associated with decontamination and waste disposal can ultimately make the nucleic acid dye expensive to use. The dye experts at Biotium developed the extremely popular GelRed® and GelGreen® fluorescent agarose gel stains to not only be the most sensitive DNA gel stains on the market, but also the safest: they are the only DNA gel stains that have been tested and found to be safe and non-toxic by independent laboratories. To learn more, visit the GelRed® and GelGreen® technology page.

Click here to download an App Note on using GelRed® and GelGreen® on the UVP GelDoc-It® imaging system. Click here to download an App Note on using GelGreen® on the UVP GelDoc-It® imaging system with the Visi-Blue™ Converter Plate.

GelRed® and GelGreen® stains are also available pre-coated to ultra-pure LE agarose. Using GelRed® Agarose & GelGreen® Agarose is easy and convenient, and obviates the need to handle concentrated fluorescent dye.

GelRed® & GelGreen® do not readily penetrate cells. HeLa cells were incubated for 30 minutes at 37°C with 1X SYBR® Safe, GelRed®, or GelGreen®. SYBR® Safe rapidly bound to DNA in live cells resulting in bright green nuclear staining. GelRed® and GelGreen® were unable to bind DNA in live cells, shown by the absence of fluorescence.

GelRed® Features:

  • Visualized with UV transilluminators using ethidium bromide detection settings
  • Most sensitive fluorescent red DNA gel stain
  • Safer and more environmentally friendly than EtBr, as well as other so-called “safe” gel stains
  • Can be used as a post-stain, or precast in agarose
  • Available as a 10,000X stock, ready-to-use 3X solution, and in 6X loading buffer format
Comparison of ethidium bromide (EtBr) and GelRed® in precast gel staining using 1% agarose gel in TBE buffer. Two-fold serial dilutions of 1 kb Plus DNA Ladder (Invitrogen) were loaded in the amounts of 200 ng, 100 ng, 50 ng and 25 ng from left to right. Gels were imaged using 300 nm transilluminator and photographed with an EtBr filter.

GelGreen® Features:

  • Visualized with blue light boxes or UV light box using SYBR® green detection settings
  • More sensitive than SYBR® Safe
  • Safer for users and the environment than SYBR® Safe and other so-called “safe” gel stains
  • Can be used as a post-stain, or precast in agarose
  • Available in a concentrated 10,000X stock
Comparison of GelGreen® and SYBR Safe in post-electrophoresis staining of 1% agarose/TBE gels. Two-fold serial dilutions (200 ng, 100 ng, 50 ng and 25 ng) of 1 kb Plus DNA Ladder (Invitrogen). Gels were imaged using 254-nm UV transilluminator and photographed with a SYBR filter.
Product Name Catalog Number Size
GelRed® 10,000X in water 41003-T 0.1 mL (Trial Size)
41003 0.5 mL
41003-1 10 mL
GelGreen® 10,000X in water 41005 0.5 mL
41005-1 10 mL
GelRed® 3X in water 41001 4 L
6X GelRed® Prestain Loading Buffer, Orange Tracking Dye 41010 1 mL
GelRed® Prestain Plus 6X DNA Loading Dye 41011 1 mL
GelRed® Agarose LE 41029-5G 5 g
41029-50G 50 g
GelGreen® Agarose LE 41030-5G 5 g
41030-50G 50 g

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PAGE GelRed® is a version of our popular GelRed® dye that was specially formulated for staining DNA in polyacrylamide gels. Like the classic GelRed®, PAGE GelRed® has also been found to be safe by independent laboratories.

Download the PAGE GelRed® Safety Report.

PAGE GelRed® Features:

  • Visualized with UV transilluminators using ethidium bromide detection settings
  • Formulated for efficient penetration and staining of polyacrylamide gels
  • Proven safe and environmentally friendly
  • Compatible with downstream cloning applications

Product Name Catalog Number Size
PAGE GelRed® 10,000X in Water 41008-T 0.1 mL
PAGE GelRed® 10,000X in Water 41008-500uL 500 uL
PAGE GelRed® 1X in Water 41014 4 L

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Choose the Right Stain for Your Application

Product / Method Procedure Advantages Disadvantages Recommended for
DNA prestaining with GelRed® Prestain Plus 6X DNA Loading Dye GelRed® loading buffer is added directly to the DNA sample before loading • Fast & simple: one-step sample loading & DNA staining

• Less concentrated dye for safer handling

• Can re-run a gel to use empty lanes
• Not recommended for PAGE, DGGE, EMSA, or PFGE gels

• Dye may cause band migration issues when loading larger amounts of DNA (more than ~100 ng/band), or for some restriction digests
• Routine agarose gels

• Recommended loading 50-200 ng ladder or 2-5 uL PCR product ( ~100 ng/band or less)
Precast staining with GelRed® 10,000X in water or GelGreen® 10,000X in water

GelRed® or GelGreen® is mixed with molten agarose before gel casting Familiar protocol, rapid results
Precast staining with GelRed® Agarose LE or GelGreen® Agarose LE
Agarose is supplied pre-coated with GelRed® or GelGreen®, just dissolve, heat, and pour Safer & more convenient, no need to handle concentrated dye
Post-electrophoresis staining with GelRed® 10,000X in water or GelGreen® 10,000X in water
– or –
GelRed® 3X in water
No fluorescent dye is added to the gel, it is stained in 3X GelRed® or 3X GelGreen® solution after electrophoresis • Most accurate sizing/sharpest bands

• Staining solution can be re-used

• Enhance sensitivity by adding NaCl
Extra staining step (up to 30 minutes) after electrophoresis (some customers report good results after only 5 minutes if dye is not reused) • Highly accurate band sizing

• Gels with more than ~100 ng DNA per band

• Analyzing restriction digests
Post-electrophoresis staining of PAGE gels using PAGE GelRed® 10,000X or 1X in water No fluorescent dye is added to the gel, it is stained in 1X PAGE GelRed® solution after electrophoresis • Formulated for efficient penetration and staining of polyacrylamide gels

• Like the classic GelRed®, it is safe and environmentally friendly
Extra staining step of approx. 30 minutes after electrophoresis Staining of nucleic acids in PAGE gels

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As Biotium continues to innovate in gel staining, we now offer a truly unique visible DNA gel stain called DNAzure®. DNAzure® dye binds to DNA in an agarose gel, and after exposure to light develops visible blue bands. The blue staining is long-lasting and doesn’t require any further light source, making it ideal for cutting out bands (no worry about UV light damaging your DNA sample or your eyes). Even more amazing is that this visible stain is more sensitive than more fluorescent DNA gel stains.

DNAzure® Features:

  • Deep blue bands visible by the naked eye following 5-30 min light exposure
  • Ultrasensitive detection, as little as ~1 ng DNA
  • Simplified DNA band excision, without the need for DNA damaging UV light
  • Expensive gel documentation systems not required for imaging
  • Compatible with downstream cloning applications
  • Bands are stable for weeks after color development
  • Also detectable on near-infrared scanners
Biotium’s 1 kb DNA ladder was loaded on a 1% agarose gel in two-fold dilutions, ranging from 200 ng to 25 ng total ladder per lane. The mass of the 500 bp band in each lane is labeled. The gel was stained with DNAzure® Blue Nucleic Acid Gel Stain for 25 minutes, and then the visible blue DNA bands were developed for 30 minutes using the Glo-Plate™ Blue LED transilluminator. The gel was placed on a white light transilluminator and imaged with a cell phone camera.
Product Name Catalog Number Size
DNAzure® Blue Nucleic Acid Gel Stain 41020 10 mL

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Still staining RNA using ethidium bromide?

Staining RNA with ethidium bromide (EtBr) requires a significant amount of the dye yet still offers very limited sensitivity for RNA when prestaining or post-staining gels. EMBER500™ was developed by Biotium scientists to offer much brighter signal and higher sensitivity than EtBr for RNA gel staining. For maximum convenience, EMBER500™ RNA Prestain Loading Dye includes formamide as well as electrophoresis tracking dyes, allowing sample denaturing, loading, tracking, and staining in a single step. The prestain is supplied as a 2X concentration, for convenient loading of sample and dye in equal volumes.

Features and benefits of EMBER500™

  • Sensitive: Brighter and much more sensitive than EtBr
  • Convenient: Denature, load, track and stain RNA samples in a single step on a regular agarose gel
  • Versatile: Stains both DNA and RNA for evaluating total RNA integrity and DNA contamination
  • Flexible Detection: Detect with UV transilluminators or blue LED gel imagers

See the Difference

Human total cellular RNA in water was mixed with EMBER500™ RNA Prestain Loading Dye or loading dye with 250 ug ethidium bromide (EtBr). Samples were heated for 10 minutes at 70°C, then run on a non-denaturing 1% agarose/1X TBE gel. From left to right, loading amounts were 200, 100, 50, or 25 ng/lane for total RNA. Lanes 1-4 used EMBER500™ RNA Prestain Loading Dye, lanes 5-8 used RNA loading dye with EtBr. The gel was imaged using a UVP GelDoc-iT® imaging system with a UV transilluminator with EtBr filter with 1.5 second exposure time.

EMBER500™ RNA Prestain Loading Dye

Product Name Catalog Number Size
EMBER500™ RNA Prestain Loading Dye 41032 4 x 1 mL
EMBER500™ RNA Prestain Loading Dye 41032-250uL 250 uL

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Go-Go™ Fast DNA Gel Running Buffer

Wish your agarose gel was done already?

Speed up routine DNA gel analysis with Biotium’s Go-Go™ Fast DNA Gel Running Buffer. This novel low ionic strength running buffer allows you to run DNA agarose gels at higher voltage to get results up to 3X faster than with TAE or TBE buffer.

  • Save time: Run your gel 3X faster than with TAE or TBE
  • Clear results: Provides crisp band resolution
  • Versatile: Excellent results with GelRed®, GelGreen®, and other popular gel stains
  • Supplied as a 50X concentrated stock solution

Go-Go™ Fast DNA Gel Running Buffer gives excellent results with GelRed® and GelGreen® DNA gel stains, as well as with GelRed® Prestain Plus 6X DNA Loading Dye. The buffer can be used with other commonly used gel stains like SYBR® Safe and ethidium bromide. Go-Go™ Fast is supplied as a convenient 50X concentrated stock solution.


Go-Go™ Fast DNA Gel Running Buffer, 50X
GelRed® Prestain Plus 6X DNA Loading Dye was used to load 1 kb DNA ladder 1% agarose gels cast in 1X Go-Go™ Fast DNA Gel Buffer (left) or 1X TBE (right). The Go-Go™ Fast gel was run at 300 V (27 V/cm) for 30 minutes, while the TBE gel was run at 100 V (9 V/cm) for 90 minutes. Lanes 1-4: 1 kb DNA Ladder from 200 ng to 25 ng per lane.

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Classic Gel Stains

Biotium offers several classic nucleic acid gel stains. Oxazole Gold (also known as SYBR® Gold) is a UV-excitable nucleic acid binding dye and is considered the most sensitive fluorescent DNA/RNA gel stain. Oxazole Gold is particularly useful for staining RNA and single-stranded oligos (see figure on right).

Thiazole Green (also known as SYBR® Green) is excitable by UV or blue light and may also be used for detection of DNA or RNA in agarose or polyacrylamide gels.

Ethidium bromide (EtBr) is widely used as a UV-excitable DNA gel stain and is a known mutagen.

Product Name Catalog Number Size
Thiazole Green (SYBR® Green I), 10,000X in DMSO 40086-0.5mL 500 uL
40086-1mL 1 mL
Oxazole Gold (SYBR® Gold), 10,000X in DMSO 40094 500 uL
Ethidium Bromide, 10 mg/mL in H2O 40042 10 mL
Single-stranded RNA ladder (NEB) or Biotium’s 1 kb DNA ladder were run on a 1% agarose TBE gel at 0.3 ug, 0.03 ug, or 0.01 ug RNA per lane, or 0.1 ug DNA per lane (from left to right). The gel was stained with 1X Oxazole Gold (aka SYBR® Gold) in 1X TBE for 30 minutes and imaged using a UV transilluminator and SYBR® Green filter.

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Gel-Bright™ Laser Diode Gel Illuminator

Novel Laser Diode Illumination for Superior Performance

Gel illuminators have traditionally relied on UV illumination for visualization of fluorescently labeled nucleic acids and proteins. However, UV-based imaging can damage skin and eyes, as well as your DNA samples. LED-based illuminators were developed as a safer alternative to UV, but often have high background and dimmer signal due to excessive ambient light and poor excitation efficiency.

In partnership with Biotium, OMEC Medical has developed a new type of gel illuminator that uses laser diodes (LDs) optimized for brighter and clearer imaging of gels. The new laser diode-based Gel-Bright™ offers better sensitivity over UV-based transilluminators when imaging green dyes such as GelGreen® or SYBR® Green, as well as significantly better performance over blue LED gel illuminators for red dyes such as GelRed®, ethidium bromide (EtBr), and One-Step Lumitein™ Protein Gel Stain.
Read the full press release.


Gel-Bright™ Laser Diode Gel Illuminator – Each, Gel-Bright™ Laser Diode Gel Illuminator

The Laser Diode Advantage:

  • Novel LD illumination: Superior performance for imaging fluorescent gels
  • Brighter signal: More sensitive than UV for green dyes
  • Versatile: Works well with both green and red dyes, unlike blue LED illuminators
  • Safer: Eliminates UV light hazards for user and DNA samples

Other Features:

  • Optimized lighting angle for even illumination
  • Adjustable light intensity
  • Multi-hinged adjustable amber filter for optimal signal
  • Easy access to the gel for gel slice excision
  • Compact and portable design

Sensitive Gel Imaging Without UV Hazards

Two-fold dilution series of Biotium’s Ready-to-Use 1 kb DNA Ladder (Cat. No. 31022) were separated on 1% agarose TBE gels pre-cast with GelRed® or GelGreen®. Total DNA loaded per lane is indicated below the gels. The same gels were imaged using a UVP GelDoc-iT® (UV), Thermo Fisher Safe Imager™ 2.0 Blue-Light Transilluminator (Safe Imager™), first generation Gel-Bright™ LED Gel Illuminator (Blue LED), or new Gel-Bright™ Laser Diode Gel Illuminator (Gel-Bright™). On GelDoc-iT®, an EtBr filter was used to image GelRed® and a SYBR® filter was used for GelGreen®. For imaging on Thermo Fisher Safe Imager™ 2.0 Blue-Light Transilluminator, Gel-Bright™ LED Gel Illuminator, and Gel-Bright™ Laser Diode Gel Illuminator, the filters supplied with each device were used to photograph both GelRed® and GelGreen® stained gels. The Gel-Bright™ Laser Diode Gel Illuminator demonstrated the brightest signal for gels stained with GelGreen® and performed comparably to the UVP GelDoc-iT® for gels stained with GelRed®.

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GelRed® Nucleic Acid Gel Stain

From: $33 Sizes: Trial size (0.1 mL), 0.5 mL, 10 mL, 4 LCatalog #:
, 41002, 41003, 41002-1, 41003-1, - 41003-TView allHide

PAGE GelRed® Nucleic Acid Gel Stain

From: $29 Sizes: 0.1 mL, 500 uL, 4 LCatalog #:
, 41008-500uL, - 41008-TView allHide

GelGreen® Nucleic Acid Gel Stain

From: $29 Sizes: Trial size (0.1 mL), 0.5 mL, 10 mLCatalog #:
, 41005, 41005-1, - 41005-TView allHide

DNAzure® Blue Nucleic Acid Gel Stain, 100X

From: $150 Sizes: 10 mLCatalog #: 41020

GelRed® Agarose LE

From: $61 Sizes: 5 g, 50 gCatalog #:
, - 41029-50GView allHide

GelGreen® Agarose LE

From: $59 Sizes: 5 g, 50 gCatalog #:
, - 41030-50GView allHide

Gel-Bright™ Laser Diode Gel Illuminator

From: $13 Sizes: EachCatalog #:
, - E90005View allHide

Agarose LE, Ultra-Pure Molecular Biology Grade

From: $70 Sizes: 25 g, 100 g, 500 gCatalog #:
, 41028-100G, - 41028-500GView allHide

TBE Buffer, 5X

From: $70 Sizes: 4 LCatalog #: 41006

Ready-to-Use 1 kb DNA Ladder

From: $94 Sizes: 150 applications (1.5 mL)Catalog #: 31022

Ready-to-Use 100 bp DNA Ladder

From: $94 Sizes: 150 applications (1.5 mL)Catalog #: 31032


GelRed® and GelGreen® Troubleshooting

Many customers use GelRed® or GelGreen® precast gels for convenience. However, because GelRed® and GelGreen® are high affinity dyes designed to be larger dyes to improve their safety, they can affect the migration of DNA in precast gels. Some samples, such as restriction digested DNA may migrate abnormally in GelRed® or GelGreen® precast gels. Tip #1: Load less DNA Smearing and smiling in GelRed® or GelGreen® precast gels most often caused by overloading of DNA. If you see band migration shifts or smearing and smiling, try reducing the amount of DNA loaded. The recommended loading amount for ladders and samples of known concentration is 50-200 ng/lane. For samples of unknown concentration, try loading one half or one third of the usual amount of DNA. This usually solves band migration problems. Tip #2: Try the post-staining protocol To avoid any interference the dye may have on DNA migration, we recommend using the post-staining protocol. If your application requires loading more than the recommended amount of DNA, use the post-staining protocol. While we recommend post-staining gels for 30 minutes, you may be able see bands in as little as five minutes, depending on how much DNA is present. Post-staining solutions can be reused. See the GelRed® Product Information Sheet or GelGreen® Product Information Sheet for detailed protocols. Other tips to improve agarose gel resolution:
  • If you see DNA migration issues or smearing after post-staining with GelRed® or GelGreen®, then the problem is not caused by the nucleic acid dye. Avoid overfilling gel wells to prevent smearing of DNA down the surface of the gel.
  • Pour a lower percentage agarose gel. Higher molecular weight DNA separates better with a lower percentage gel.
  • Change the running buffer. TBE buffer has a higher buffering capacity than TAE buffer.

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There are a few possibilities:
  1. The dye may have precipitated out of solution.
    • Heat the GelRed® or GelGreen® solution to 45-50°C for two minutes and vortex to dissolve.
    • Store dye at room temperature to avoid precipitation.
  2. If you are seeing high background staining of the gel, the agarose that you are using may be of low quality. Contaminants in the agarose may bind to the dye, resulting in increased background.

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GelRed® and GelGreen® Nucleic Acid Gel Stains

Most of our products are stable at room temperature for many days, so in all likelihood the product will still work just fine. To be on the safe side, we recommend performing a small scale positive control experiment to confirm that the product still works for your application before processing a large number of samples or precious samples. One exception that we are aware of is GelGreen™, which is more sensitive to light exposure than most of our other fluorescent dyes. If GelGreen™ is exposed to ambient light for a prolonged period of time (days to weeks), its color will change from dark orange to brick red. If this occurs, the GelGreen will no longer work for gel staining.  

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The main difference between GelRed® and GelGreen® is their fluorescence excitation and emission wavelengths. GelRed® has red fluorescence, similar to ethidium bromide. GelGreen® has green fluorescence, similar to SYBR® Green or SYBR® Safe. Both dyes are compatible with standard UV transilluminators. GelGreen® is also compatible with blue light transilluminators, which allow users to avoid exposing themselves and their DNA samples to ultraviolet radiation. GelRed® and GelGreen® have higher sensitivity for double stranded nucleic acids compared to single stranded nucleic acids, but GelRed® is more sensitive for staining single stranded nucleic acids than GelGreen®. GelRed® is about twice as sensitive for double stranded nucleic acids compared to single-stranded nucleic acids, and about five times more sensitive than GelGreen® for staining single stranded nucleic acids. For more information about these products, please visit our DNA stains technology page.

View the GelRed® Product Line

View the GelGreen® Product Line

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The water formulation is a newer and improved product compared to the stock in DMSO. We recommend using dyes in water to avoid the potential hazards of handling DMSO, which can be absorbed through the skin. We continue to offer dyes in DMSO because some users do not wish to alter their established laboratory protocols. Based on internal testing, both formulations perform similarly.

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DNAzure® Visible DNA Gel Stain

We have tested a variety of different light sources for the development of DNAzure® bands in an agarose gel. We have found that most light sources will work, but how long the development takes is dependent on the brightness of the light. The fastest band development is seen with our Gel-Bright™ and Glo-Plate™ Blue LED illuminators. We have also seen good results with other bright, white LED lights. Other light sources that work but take more time include an LED desk lamp and a cell phone light. We found that a 600W halogen lamp did not work well- it was too hot, which melted the gel.

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For optimal staining, we recommend diluting the 100X DNAzure® stock to 1X working solution fresh each time. However, if a 1X solution stored at 4°C and protected from light, the gel stain should to be good up to two weeks.

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Yes, the 1X DNAzure® staining solution can be re-used for multiple gels, under certain conditions. Importantly, the staining solution must be removed from the gel before the gel is exposed to light to develop the bands. If the staining solution undergoes the light exposure, it will not be able to stain another gel. The used staining solution should be stored in the refrigerator, protected from light, between uses. We have successfully re-used the staining solution stored for up to 2 weeks, and used up to 4 times with little loss of signal (after 5 or 6 uses, the sensitivity was noticeably lower).

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