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PROTEIN DETECTION, QUANTITATION & ANALYSIS

Gel stains, thermal stability assay & more

Biotium offers innovative solutions for protein detection and analysis. Jump to a section below to learn more:

Fast, easy & non-toxic One-Step Stains
Super-sensitive protein band quantitation in gels or blots
GloMelt™ is highly sensitive & tolerant of detergent
AccuOrange™ highly sensitive fluorescence protein assay
Conjugates and accessories for western blotting

One-Step Blue® & One-Step Lumitein™ Protein Gel Stains

Our One-Step protein gel stains are low-cost, quick, and easy-to-use. Simply add stain to your SDS-PAGE gel without fixing or washing, and stain for 5 to 60 min. These stains are non-toxic for safer handling, and are certified under CCR Title 22 as non-hazardous for drain disposal after pH neutralization. One-Step Blue® replaces Coomassie® for visible staining or near-IR fluorescence. One-Step™ Lumitein replaces SYPRO® Ruby for UV box or gel scanner, and One-Step™ Lumitein UV replaces Oriole™ for UV transilluminator.

One-Step Stains Features

  • Fast, simple staining
  • No fixing, microwaving, or washing
  • Aqueous-based and non-toxic for drain disposal

One-Step Blue® is an alternative to time consuming Coomassie® staining, for fast and easy visible staining (left) or near-infrared imaging in the LI-COR® Odyssey® 800 channel (right).
Red fluorescent One-Step Lumitein™ is an alternative to time-consuming and expensive SYPRO® Ruby protein gel stain, and it can be imaged on a UV box or fluorescence gel scanner
Red fluorescent One-Step Lumitein™ UV Protein Gel Stain is designed for imaging using a UV transilluminator. It is an alternative to Oriole™ Gel Stain, but does not contain hazardous solvents and does not cause gel shrinkage.

Product Information

ProductReplacement forCatalog numberUnit sizeProduct protocolSafety report
One-Step Blue®
Coomassie stain21003-1L1LPI-21003


One-Step Gel Stains Safety Report
One-Step Lumitein™SYPRO® Ruby Protein Gel Stain21004-1L1LPI-21004
21004-4L4L
One-Step Lumitein™ UVOriole™ Protein Gel Stain21005-1L1LPI-21005
21005-4L4L

Lumitein and its related technologies are covered by US and international patents. SYPRO is a registered trademark of Molecular Probes, Inc. Oriole is a trademark of Bio-Rad Laboratories. Coomassie is a registered trademark of Imperial Chemical Industries.

 

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Mix-n-Stain™ Near-IR Total Protein Prestain Kits

Mix-n-Stain™ Total Protein Prestain Kits allow simple and highly sensitive protein quantitation on SDS-PAGE gels and western blot membranes. The kits allow you to label purified proteins or cell lysates with our near-infrared CF® dyes before running the samples on SDS-PAGE. After electrophoresis, the bands can be visualized using a fluorescent gel scanner, allowing detection of as little as 1 ng protein per band. Labeled proteins also can be transferred to membranes for western blotting. The staining demonstrates excellent linearity for quantitation of total protein over a wide dynamic range, outperforming traditional western blot normalization based on housekeeping protein detection.

Mix-n-Stain™ Total Protein Prestain Features

  • Highly sensitive protein quantitation on PAGE gels or western membranes
  • Fast and simple labeling of proteins or lysates, no purification required
  • Detect as little as 1 ng protein in gel
  • Superior linearity for western normalization compared to housekeeping proteins

In-gel fluorescence image of bovine serum albumin (BSA) labeled with the CF®680T total protein prestaining kit on SDS-PAGE gel. Protein content for each lane ranges from 10 ug to 1 ng, from left to right. The bands above and below the major bands are from impurity proteins in the BSA sample. The excess dye runs to the very bottom of the gel. Inset: part of the image with enhanced brightness to visualize the bands with 10, 5, and 1 ng of BSA.
Mix-n-Stain™ total protein prestaining kits for western blot normalization. HeLa cell lysate in serial dilution was labeled with (A) the CF®770T total protein prestain before SDS-PAGE and transfer to PVDF, or (B) mouse anti-tubulin primary antibody and CF®770T goat anti-mouse secondary antibody after transfer to PVDF. (C) Plots of band intensity vs protein content for CF®770T labeled lysate (shown in A), CF®680T labeled lysate (membrane not shown), and tubulin WB (shown in B). The Mix-n-Stain™ total protein prestaining kits show better linearity compared to housekeeping protein detection.

Product Information

ProductCatalog numberSizeAbs/EmImaging Systems / Detection channels
Mix-n-Stain™ CF®680T Total Protein Prestain Kit92400-T200 labelings681 / 698 nmAmersham Typhoon™ Trio Cy®5 channel
Amersham Typhoon™ 5 IR short channel
LI-COR® Odyssey® 700 channel
924001000 labelings
Mix-n-Stain™ CF®770T Total Protein Prestain Kit92401-T200 labelings764 / 787 nmAmersham Typhoon™ 5 IR long channel
LI-COR® Odyssey® 800 channel
924011000 labelings

Typhoon is a trademark and Cy dye is a registered trademark of GE Healthcare; Odyssey is a registered trademark of LI-COR Biosciences.

 

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GloMelt™ Protein Thermal Stability Assay

Thermal shift assay for protein stability

The thermal shift assay, also called Protein Thermal Shift™, differential scanning fluorimetry, or Thermofluor assay, is a simple technique for measuring protein denaturation temperature. It can be used to screen conditions that affect protein thermal stability, such as mutations, ligand binding, and buffer formulations. The assay is rapid and is performed on a quantitative PCR system. Thermal shift is compatible with high throughput screening and requires much less protein than methods like circular dichroism and differential scanning calorimetry.

Environmentally sensitive fluorescent dyes can be used to monitor the temperature dependent unfolding of a protein. The protein’s melting temperature (Tm) is a reporter of the protein’s thermal stability.

GloMelt™ Dye for protein thermal stability

GloMelt™ dye undergoes fluorescence enhancement upon binding to hydrophobic regions of denatured proteins, and can be used to detect protein unfolding in thermal shift assay. GloMelt™ dye is optimized for detection in the SYBR® Green channel, so it generates much stronger signal than SYPRO® Orange and PROTEOSTAT® TS dyes, which have spectra that are not well-matched to common qPCR fluorescence channels. Because GloMelt™ has green fluorescence, it also can be used with ROX normalization for improved replicate consistency.

GloMelt™ tolerates a wide variety of common stabilizers and destabilizers, and unlike SYPRO® Orange, it performs well in the presence of detergents. SYPRO® Orange and PROTEOSTAT® TS dyes are highly hydrophobic, so after dilution in buffer the dyes must be used immediately. In contrast, GloMelt™ has excellent water solubility, allowing storage of diluted dye solutions for greater convenience and less wasted dye.

GloMelt™ Features

  • Green fluorescence optimal for qPCR instruments and ROX normalization
  • Compatible with high detergent concentrations
  • Compatible with wide pH range, reducing agents, and common buffers/excipients
  • Great for high throughput assays, low reaction volumes and low protein concentrations
  • Highly soluble and stable in aqueous buffers

GloMelt™ has much better detergent tolerance than SYPRO® Orange. IgG melt curve plots in the presence of detergent. A thermal shift assay was performed on 20 ug IgG in the presence of 5X SYPRO® Orange or 1X GloMelt™ dye, using a QuantStudio™ 5 qPCR system. The presence of detergent inhibited the SYPRO® Orange assay, but had little affect on the GloMelt™ curve.
GloMelt™ tolerates reducing agents, unlike PROTEOSTAT® TS. IgG melt curve plots in the presence of DTT. A thermal shift assay was performed on 25 ug IgG in the presence of 1X PROTEOSTAT® TS dye or 1X GloMelt™ dye, using a QuantStudio™ 5 qPCR system. The presence of DTT drastically reduced the sensitivity of the PROTEOSTAT® assay, but had little affect on the GloMelt™ dye. As expected, DTT reduced IgG thermal stability.
Normalization of GloMelt™ signal to ROX reference dye can improve results by increasing replicate consistency. A thermal shift assay was performed on 20 ug IgG in the presence 1X GloMelt™ dye and 50 nM ROX. After ROX normalization the standard deviation was reduced more than 5-fold.

Product Information

ProductKit contentsCatalog numberSize*
GloMelt™ Kit• GloMelt™ Dye
• Goat IgG Control
33021-T200 reactions
33021-12000 reactions
GloMelt™ Kit with ROX• GloMelt™ Dye
• Goat IgG Control
• ROX Reference Dye
33022-T200 reactions
33022-12000 reactions
* Size based on 20 uL reaction volume

SYPRO is a registered trademark of Thermo Fisher Scientific; Protein Thermal Shift and QuantStudio are trademarks of Thermo Fisher Scientific; PROTEOSTAT is a registered trademark of Enzo Life Sciences.

 

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AccuOrange™ Fluorescent Protein Quantitation Assay

AccuOrange™ Protein Quantitation Kit is a highly sensitive fluorescence-based assay for quantitating purified protein or antibody samples in 96-well format. The detection range of the assay is 0.1-15 ug/mL protein. AccuOrange™ is much more sensitive than traditional protein quantitation assays such as BCA, Bradford and Lowry, and is more linearity and reproducible compared to the NanoOrange® protein quantitation assay. The assay shows minimal variability between different proteins, and has stable fluorescence signal for up to 16 hours. The AccuOrange™ assay has low tolerance for detergents, and is not recommended for use with cell lysates.

The AccuOrange™ fluorescent protein quantitation assay is more  linear and less variable than the NanoOrange® assay.
AssayDetection RangeComments
AccuOrange™0.1-15 ug/mLFluorescence-based (480/598 nm)
Highly linear
Signal stable for at least 16 hours
Compatible with reducing agents
Not compatible with detergents
NanoOrange®0.1-10 ug/mLFluorescence-based (470/570 nm)
Non-linear
Fluorescence stable for 6 hours
Compatible with reducing agents
Not compatible with detergents
Modified Lowry1-1500 ug/mLAbsorbance-based (750 nm)
Non-linear
Not compatible with reducing agents or detergents
BCA20-2000 ug/mLAbsorbance-based (562 nm)
Highly linear
Signal not stable over time
Not compatible with reducing agents
Compatible with detergents
Bradford (Coomassie®)50-500 ug/mLAbsorbance-based (595 nm)
Signal not stable over time
Non-linear
Compatible with reducing agents
Not compatible with detergents
Pierce® 660 nm50-2000 ug/mLAbsorbance-based (660 nm)
Non-linear
Compatible with reducing agents & detergents
A28050-2000 ug/mLAbsorbance-based (280 nm)
High protein-protein variability
Contaminants and detergents can affect results

Product Information

ProductCatalog numberSizeFeatures
AccuOrange™ Protein Quantitation Kit30071-T200 assays• Highly sensitive: detect 0.1-15 ug/mL protein
• Excellent linearity and low variability
• Stable fluorescence signal
• Compatible with reducing agents and other additivies
• For use with purified protein or antibody samples
300711000 assays

NanoOrange is a registered trademark and Pierce is a trademark of Thermo Fisher Scientific; Coomassie is a registered trademark of Imperial Chemical Industries.

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Conjugates and accessories for western blotting

Near-infrared (near-IR) western detection is highly sensitive, and offers advantages of wider linear range and multiplexing capability compared to chemiluminscence detection (see our webinar to learn more). Biotium’s near-IR CF® dyes are the brightest and most photostable available. Learn more about CF®680 and CF®770 dyes for near-IR western, In Cell Western®, and other applications.

We offer wide selection of primary and secondary antibodies conjugated to our exceptional near-IR CF® dyes for western blot, as well as HRP conjugates for chemiluminescence detection. Also see below for our selection of protein markers, buffers, blocking agents, and more for western blotting.

CF® dye conjugates are brighter than IRDye® conjugates for near-infrared western blotting. A dilution series of HeLa cell lysate (from 2 ug to 0.125 ug) was transferred to PVDF membranes. Mouse anti-tubulin and rabbit anti-COX IV antibodies were detected using CF®680 anti-mouse and CF®770 anti-rabbit, or the corresponding IRDye® conjugates, and scanned on LI-COR® Odyssey®. Band quantitation showed ~50% brighter signal with CF® dyes. M: marker.
Peacock™ and Peacock™ Plus Prestained Protein Markers on 10% Bis-Tris MES gels, labeled with apparent molecular weights of the bands.

Product Information

ProductCatalog No.SizeFeatures
Peacock™ Prestained Protein Marker2153050 uL or 500 uL• Visible color protein marker for SDS-PAGE and western
• 8 blue bands ranging from 10 kDa to 180 kDa
• Red/green bands at 75 kDa/25 kDa
Peacock™ Plus Prestained Protein Marker2153150 uL or 500 uL• Visible color protein marker for SDS-PAGE and western
• 10 blue bands ranging from 8 kDa to 245 kDa
• Red/green bands at 75 kDa/25 kDa
10X Phosphate Buffered Saline (PBS)220204L Cubitainer®• Concentrated PBS Buffer
• RNase-, DNase-, protease-free (non-sterile)
10X Fish Gelatin Blocking Agent22010100 mL• Provides excellent blocking for immunofluorescence or western
• Add to buffer of your choice (PBS or TBS)
• Compatible with goat and sheep primaries, unlike BSA, milk, or goat serum
Fish Gelatin Powder220112 x 50 g• Gelatin from cold water fish skin for blocking for immunofluorescence or western
• Compatible with goat and sheep primaries, unlike BSA, milk, or goat serum
Bovine Serum Albumin, 30% Solution22014100 mL• Commonly used blocking agent and antibody or protein stabilizer
• 30% solution in water
• Made from IgG-free, protease-free Fraction V BSA
Bovine Serum Albumin Fraction V2201350 g• Commonly used blocking agent and antibody or protein stabilizer
• IgG-free, protease-free Fraction V BSA
Dry Milk Powder220124 x 25 g• Nonfat dry milk
• Commonly used blocking agent for western
Tween®-202200250 mL• Detergent commonly used for western blocking and washing
Mini Cell Scrapers22003Pack of 200• For harvesting cells or cell lysates from 96-, 48- and 24-well plates
• 0.5 cm (3/16″) wide and 6 cm (2 3/8″) long
• 20 packs of 10 scrapers per pack
• Polyethylene, disposable & sterile
Ultrafiltration Vials (3K MWCO)22018Pack of 5• For removing buffers, salts, and free dyes from proteins or DNA
• Simple microcentrifuge spin-column format
• 3 kDa molecular weight cut-off (MWCO)
Ultrafiltration Vials22004Pack of 5• For removing buffers, salts, and free dyes from proteins or DNA
• Simple microcentrifuge spin-column format
• 10 kDa molecular weight cut-off (MWCO)
DTT910501 g• Reducing agent commonly used to prepare samples for SDS-PAGE
TCEP910491 g• Odorless reducing agent
• More effective and stable than DTT
TWEEN is a registered trademark of Croda International PLC; Cubitainer is a registered trademark of The Hedwin Division.

LI-COR, Odyssey, IRDye, and In Cell Western are registered trademarks of LI-COR Biosciences.

 

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One-Step Blue Protein Gel Stain

From: $89 Sizes: 1 LCatalog #: 21003-1L

One-Step Lumitein Protein Gel Stain

From: $115 Sizes: 1 L, 4 LCatalog #: 21004-1L, - 21004-4LView allHide

One-Step Lumitein UV Protein Gel Stain

From: $155 Sizes: 1 L, 4 LCatalog #: 21005-1L, - 21005-4LView allHide

Peacock Prestained Protein Marker

From: $55 Sizes: 50 uL, 500 uLCatalog #: 21530-50uL, - 21530-500uLView allHide

Peacock Plus Prestained Protein Marker

From: $60 Sizes: 50 uL, 500 uLCatalog #: 21531-500uL, - 21531-50uLView allHide

AccuOrange Protein Quantitation Kit

From: $47 Sizes: Trial size (200 assays), 2,000 assaysCatalog #: 30071, - 30071-TView allHide

GloMelt Thermal Shift Protein Stability Kit

From: $180 Sizes: 200 assays, 2,000 assaysCatalog #: 33021-T, 33022-T, 33021-1, - 33022-1View allHide

Mix-n-Stain Total Protein Prestain Kits

From: $100 Sizes: 200 labelings, 1000 labelingsCatalog #: 92400-T, 92400, 92401-T, - 92401View allHide

Protein Detection & Analysis

Gel stains, protein quantitation and stability assays, plus accessories for western blotting.

Buffers & Accessories

Buffers and other accessories for immunofluorescence staining and other applications.