Shop All General Immunoassay Buffers & Reagents

Guardian™ Peroxidase Conjugate Stabilizer/Diluent (Thermo Scientific™)

Thermo Scientific Guardian Peroxidase Conjugate Stabilizer/Diluent preserves the functional integrity and activity of horseradish peroxidase conjugated antibodies and other proteins at very dilute concentrations for long-term storage.

Features of Guardian Peroxidase Conjugate Stabilizer/Diluent:

Preserves HRP activity—no significant loss of HRP activity over a six-month period at room temperature (1:1000 dilution) or 12 months at 4°C
Convenient—store ready-to-use dilutions (1:1000 to 1:100,000) that maintain enzyme activity in the refrigerator—no aliquoting or freezing
Assay compatible—simply add your favorite blocking buffer to create the ideal diluent for your HRP-based ELISA system or store the HRP conjugate as a 1:1000 stock solution for Western blots and dilute in the final assay buffer
Saves money—less expensive than competitor formulations or ordering new HRP conjugates

With Guardian Peroxidase Conjugate Stabilizer/Diluent, typical 1 mg/mL antibody or streptavidin peroxidase conjugates can be diluted as much as 100,000-fold for storage at 4°C. Most ELISA and blotting applications for HRP conjugates require dilution of typical 1 mg/mL stocks by at least 1000-fold (to 1 µg/mL). Sensitive assay systems, such as with chemiluminescent substrates, often require dilution up to 100,000-fold (10 ng/mL). The Guardian Solution enables these 1X working concentrations of HRP conjugate to be prepared in advanced and stored at 4°C for 12 months or at room temperature for six months.For blotting applications, it is usually best to prepare a concentration for storage that can be diluted 10-fold in assay buffer (which may contain blocking components) for final use.

Typical colorimetric ELISA procedures requires that 10 mL of HRP-conjugated secondary antibody be diluted 1000- to 5000-fold from a 1 mg/mL stock solution. That necessitates pipetting 2 to 10 µL of stock into a tube with 10 mL of diluent. More sensitive assay systems, such as Western blots with Thermo Scientific SuperSignal West Pico, Dura or Femto Chemiluminescent Substrates for HRP, require a second round of dilution to achieve the needed working concentration of HRP conjugate. With Guardian Stabilizer-Diluent, HRP conjugates can be pre-diluted and stored at concentrations that are either ready to use or easily diluted 10- to 100-fold for final use. Preparing larger volumes of pre-diluted stocks ensures consistency and greater accuracy for assays performed repeatedly day after day.

StartingBlock™ (PBS) Blocking Buffer (Thermo Scientific™)

StartingBlock Blocking Buffer is a single purified protein for fast blocking of western blots and ELISA assays. It provides broad compatibility with a wide range of antibodies, antibody combinations, and other protein probing and assay systems. StartingBlock buffer is available in PBS and TBS with and without Tween20.

Compare and view all available blocking buffers

Features of StartingBlock Blocking Buffers:
Strip and reprobe without reblocking—blots stay blocked even after stripping with Thermo Scientific Restore Stripping Buffer (Cat. No. 21059)
Compatible with many detection systems—western blot, ELISA, and IHC with antibody or avidin/biotin probes (blocker is serum and biotin-free)
Short blocking times—less than 15 minutes for nitrocellulose or PVDF membranes, almost instantaneous for polystyrene microplate wells
Biotin- and serum protein-free formulation

Related products
StartingBlock T20 (PBS) Blocking Buffer
StartingBlock (TBS) Blocking Buffer
StartingBlock T20 (TBS) Blocking Buffer

Pierce™ Clear Milk Blocking Buffer (10X) (Thermo Scientific™)

Pierce Clear Milk Blocking Buffer (10X) is a long-shelf life, high-performance replacement for homemade non-fat milk blocking buffers in western blotting applications.

Compare and view all available blocking buffers

Our Clear Milk Blocking Buffer (10X) is a pre-formulated milk solution, clarified and stabilized for blocking excess nonspecific binding sites, reducing background in western blotting applications and diluting antibodies when used with nitrocellulose and PVDF membranes. It provides lower background, enhanced sensitivity, extended shelf life, and reproducible results compared to homemade buffers based on dissolved non-fat dry milk. Not recommended for avidin-based techniques because it contains some endogenous biotin.

SuperBlock™ T20 (PBS) Blocking Buffer (Thermo Scientific™)

SuperBlock Blocking Buffer is optimized solution containing a single purified glycoprotein that provides incredibly fast and effective blocking for ELISA, IHC, and western blot analysis.

Compare and view all available blocking buffers

Features of SuperBlock Blocking Buffer:
Blocking time—block membranes in 5 to 10 minutes and ELISA plates in 2 minutes
Applications—ELISA, western blotting, IHC; biotin-free for use with streptavidin system
Stability—store buffer at 4°C for one year; store blocked plates dry for up to 12 months

Blocking micro-plates, membranes or tissues with a SuperBlock Buffer yields a high signal-to-noise ratio in most detection systems. The protein-based formulation does not contain any immunoglobulins, albumin, or endogenous biotin, making it compatible in many situations where traditional blocking agents fail. The buffer is especially effective at blocking coated polystyrene microplates (96-well plates) and stabilizing them for drying and storage for later use.

Related products
SuperBlock (PBS) Blocking Buffer
SuperBlock (TBS) Blocking Buffer
SuperBlock T20 (TBS) Blocking Buffer
SuperBlock (TBS) Blocking Buffer Dry Blend

StartingBlock™ (TBS) Blocking Buffer (Thermo Scientific™)

StartingBlock Blocking Buffer is a single purified protein for fast blocking of western blots and ELISA assays. It provides broad compatibility with a wide range of antibodies, antibody combinations, and other protein probing and assay systems. StartingBlock buffer is available in PBS and TBS with and without Tween20.

Compare and view all available blocking buffers

Features of StartingBlock Blocking Buffers:
Strip and reprobe without reblocking—blots stay blocked even after stripping with Thermo Scientific Restore Stripping Buffer (Cat. No. 21059)
Compatible with many detection systems—western blot, ELISA, and IHC with antibody or avidin/biotin probes (blocker is serum and biotin-free)
Short blocking times—less than 15 minutes for nitrocellulose or PVDF membranes, almost instantaneous for polystyrene microplate wells
Biotin- and serum protein-free formulation

Related products
StartingBlock (PBS) Blocking Buffer
StartingBlock T20 (PBS) Blocking Buffer
StartingBlock T20 (TBS) Blocking Buffer

I-Block™ Protein-Based Blocking Reagent (Invitrogen™)

I-Block reagent is a highly purified casein-based blocking reagent. It provides superior blocking compared to both dried milk and BSA. Unlike other casein-based blocking reagents, I-Block reagent is essentially biotin-free. I-Block reagent is tested in assays using Tropix substrates and alkaline phosphatase conjugates, and is useful as a blocking reagent in membrane-based and immunoassay applications.

The suggested working concentration is 0.2% (w/v) for detection of nucleic acids on neutral or positively-charged nylon membranes and for immunoassays and protein detection on membranes (nitrocellulose, PVDF, or neutral nylon). For protein detection on positively-charged nylon membrane (such as TropilonPlus membrane), a concentration of 3% is recommended. I-Block blocking solution is prepared in either Tris- or phosphate-buffered saline buffer with heating (40-50°C).

This casein-based blocking reagent can be used with Western-Light, Western-Light Plus, Western-Star, ELISA-Light, Southern-Light, and Southern-Star detection systems.

cAMP-Screen™ Wash Buffer (Invitrogen™)

This Wash Buffer is suitable for use with the cAMP-Screen® or cAMP-Screen Direct® Immunoassay system.

For Research Use Only. Not for use in diagnostics procedures.

Miser™ Antibody Extender Solution NC (Thermo Scientific™)

Thermo Scientific Pierce Antibody Extender Solution NC is a post-transfer nitrocellulose membrane-treatment reagent that enables Western blot detection with much less primary antibody.

Features of Antibody Extender Solution NC:

Achieve equivalent signal—use at least three times less primary antibody than normal and retain comparable or better signal detectability
Any detection mode or enzyme—the method works with both colorimetric and chemiluminescent detection modes and with horseradish peroxidase (HRP) and alkaline phosphatase (AP) systems
Easy-to-perform, 10-minute protocol—invest a few minutes and save money on your primary antibody; our scientists have reduced their use of expensive primary antibodies by up to 100-fold with this product

By treating nitrocellulose membranes for a few minutes in this reagent immediately after transfer and before probing, you can use much less (more dilute) primary antibody solutions while obtaining the same level of detection. This conserves use of expensive and rare antibodies, enabling more experiments to be performed with the same amount of antibody. The reagent is so effective that our scientists have observed antibody cost reductions of 10-, 25- and even 100-times (depending on the antigen and primary antibody directed against that antigen).

SuperBlock™ (PBS) Blocking Buffer - Blotting (Thermo Scientific™)

Thermo Scientific SuperBlock (PBS) Blocking Buffer - Blotting is optimized PBS solution containing a protein that provides incredibly fast and effective blocking for Western blot analysis.

Features of SuperBlock (PBS) Blocking Buffer - Blotting:

Fast—block membranes in 5 to 10 minutes
Flexible—guaranteed to be biotin-free for use with streptavidin system
Low background—the non-serum protein solution yields a high signal-to-noise ratio
Stable—store buffer at 4°C for one year; store blocked plates dry for up to 12 months

Blocking micro-plates, membranes or tissues with a SuperBlock Buffer yields a high signal-to-noise ratio in most detection systems. The protein-based formulation does not contain any immunoglobulins, albumin or endogenous biotin, making it compatible in many situations where traditional blocking agents fail. The buffer is especially effective at blocking coated polystyrene microplates (96-well plates) and stabilizing them for drying and storage for later use.

Related Products
SuperBlock™ (PBS) Blocking Buffer
SuperBlock™ T20 (PBS) Blocking Buffer
SuperBlock™ (TBS) Blocking Buffer
SuperBlock™ T20 (TBS) Blocking Buffer
SuperBlock™ (TBS) Blocking Buffer Dry Blend

Normal Horse Serum (Invitrogen™)

Normal Horse Serum Control for IF, ICC, IHC, BLOCK, Ctrl

Pierce™ Protein-Free (PBS) Blocking Buffer (Thermo Scientific™)

Pierce Protein-Free Blocking Buffer is a non-protein compound that provides effective blocking for membrane-based and plate-based protein detection methods, resulting in extremely low background. It is supplied in a ready-to-use format.

Compare and view all available blocking buffers

Features of Protein-Free Blocking Buffer:
Protein-free blocker—minimizes or eliminates cross-reactivity associated with protein-based blocking buffers
Applications—western blotting (membranes), ELISA (microplates), and arrays (coated glass slides)
Streptavidin-friendly—free of biotin; no interference with avidin-biotin detection systems
High-performance—optimized and validated in many protein methods to provide high signal-to-noise ratio (i.e., no quenching of specific binding and signal but eliminating nonspecific binding and background)

Traditional blocking buffers contain proteins that can cross-react in certain immunodetection systems, resulting in high background and reduced signal. Pierce Protein-Free Blocking Buffers are devoid of protein while remaining highly effective at blocking plates, membranes, and other surfaces for ELISA, western blotting, glass slide arrays, and other applications.

Related products
Pierce Protein-Free T20 (PBS) Blocking Buffer
Pierce Protein-Free (TBS) Blocking Buffer
Pierce Protein-Free T20 (TBS) Blocking Buffer

Pierce™ Fast Blocking Buffer (Thermo Scientific™)

Pierce Fast Blocking Buffer effectively and reliably blocks western blots in just five minutes to provide low-background results for traditional western blotting protocols.

Compare and view all available blocking buffers

Pierce Fast Blocking Buffer streamlines western blot protocols by providing consistent, high-quality blocking for nitrocellulose or PVDF membranes in only five minutes, producing results comparable to traditional blockers. Blocking and probing steps with Fast Blocking Buffer prevent nonspecific binding of detection antibodies during probing steps but allows specific detection to occur. Pierce Fast Wash Buffer provides efficient membrane washing after incubation with a primary and secondary antibody to effectively shorten total washing time to 20 minutes (from the typical 90 minutes). This buffer is compatible with antibodies and biotin-avidin systems, as well as both nitrocellulose and PVDF membranes.

Related products
Pierce Fast Wash Buffer, 10X

Pierce™ Protein-Free T20 (TBS) Blocking Buffer (Thermo Scientific™)

Pierce Protein-Free Blocking Buffer is a non-protein compound that provides effective blocking for membrane-based and plate-based protein detection methods, resulting in extremely low background. It is supplied in a ready-to-use format.

Compare and view all available blocking buffers

Features of Protein-Free Blocking Buffer:
Protein-free blocker—minimizes or eliminates cross-reactivity associated with protein-based blocking buffers
Applications—western blotting (membranes), ELISA (microplates), and arrays (coated glass slides)
Streptavidin-friendly—free of biotin; no interference with avidin-biotin detection systems
High-performance—optimized and validated in many protein methods to provide high signal-to-noise ratio (i.e., no quenching of specific binding and signal but eliminating nonspecific binding and background)

Traditional blocking buffers contain proteins that can cross-react in certain immunodetection systems, resulting in high background and reduced signal. Pierce Protein-Free Blocking Buffers are devoid of protein while remaining highly effective at blocking plates, membranes, and other surfaces for ELISA, western blotting, glass slide arrays, and other applications.

Related products
Pierce Protein-Free (PBS) Blocking Buffer
Pierce Protein-Free T20 (PBS) Blocking Buffer
Pierce Protein-Free (TBS) Blocking Buffer

Blocker™ FL Fluorescent Blocking Buffer (10X)

Blocker FL Fluorescent Blocking Buffer is designed to block excess nonspecific binding sites to help reduce background fluorescence in western blotting applications. Blocker FL buffer helps enhance fluorescent protein detection by increasing the signal-to-noise ratio in blotting applications where background fluorescence may otherwise interfere with signal detection.

Compare and view all available blocking buffers

Working reagent is prepared by adding 1 part Blocker FL buffer to 9 parts ultrapure water. Optimal concentration should be determined empirically for each system. Compatible with both nitrocellulose and PVDF membranes.

Pierce™ Stable Peroxide Substrate Buffer (10X) (Thermo Scientific™)

Thermo Scientific Pierce Stable Peroxide Substrate Buffer (10X) include optimized, reliable and convenient stock solutions of peroxide for HRP-based assays detection.

Features of Stable Peroxide Substrate Buffer (10X):

• Ready-to-use
• Minimize assay-to-assay variability

Buffered stable hydrogen peroxide (H2O2) is used by researchers who prefer to make their own HRP-ELISA substrates. This is easily done by adding a chromogen of choice to the buffer. Stable Peroxide Substrate Buffer has a long shelf life (12 months after receipt) and is provided as a 10-fold concentrate. A total volume of 1000 mL can be made from one 100 mL bottle of concentrate. If you use 10 mL of substrate per plate, this will allow you to make substrate for 100 plates from only one bottle of Stable Peroxide Substrate Buffer.

Related Products
Pierce™ Diethanolamine Substrate Buffer (5X)

SuperBlock™ (PBS) Blocking Buffer (Thermo Scientific™)

SuperBlock Blocking Buffer is an optimized solution containing a single purified glycoprotein that provides incredibly fast and effective blocking for ELISA, IHC, and western blot analysis.

Compare and view all available blocking buffers

Features of SuperBlock Blocking Buffer:
Blocking time—block membranes in 5 to 10 minutes and ELISA plates in 2 minutes
Applications—ELISA, western blotting, IHC; biotin-free for use with streptavidin system
Stability—store buffer at 4°C for one year; store blocked plates dry for up to 12 months

Blocking micro-plates, membranes or tissues with a SuperBlock Buffer yields a high signal-to-noise ratio in most detection systems. The protein-based formulation does not contain any immunoglobulins, albumin, or endogenous biotin, making it compatible in many situations where traditional blocking agents fail. The buffer is especially effective at blocking coated polystyrene microplates (96-well plates) and stabilizing them for drying and storage for later use.

Related products
SuperBlock T20 (PBS) Blocking Buffer
SuperBlock (TBS) Blocking Buffer
SuperBlock T20 (TBS) Blocking Buffer
SuperBlock (TBS) Blocking Buffer Dry Blend

Pierce™ Immunostain Enhancer (Thermo Scientific™)

Thermo Scientific Pierce Immunostain Enhancer enables significant antibody dilution (5- to 20-fold beyond normal) to increase signal intensity 3- to 12-fold in immunostaining applications with chromogenic or fluorescent substrates.

Features of Immunostain Enhancer:

Save precious antibody—Pierce Immunostain Enhancer allows the customer to use only a fraction of antibody to achieve the same signal as with conventional immunodetection
Convenience—simply replace your current antibody dilution buffer with Pierce Immunostain Enhancer (unlike other signal enhancement methods which require additional steps)
Increased signal intensity and sensitivity—provides 3- to 12- fold increase in signal intensity and sensitivity for improved visualization of the antigen of interest in cells and tissues
Improved specificity—significantly improves signal-to-noise ratio for poor quality and low affinity antibodies
Compatible—can be used with chromogenic and fluorescent detection methods

This ready-to-use enhancer for immunohistochemical staining does not add steps to the workflow because it is used to dilute the primary and secondary antibodies. The Pierce Immunostain Enhancer is compatible with fluorescence and chromogenic detection and routinely increases both signal intensity and detection sensitivity. Signal enhancement is antibody-dependent and typically ranges from 3- to 12-fold. Because of the strong signal enhancement, the Pierce Immunostain Enhancer reduces the amount of antibody required to achieve optimal detection.

The Pierce Immunostain Enhancer enables significant dilution of primary and secondary antibodies. Dilution 5- to 20-fold beyond the antibody vendor's recommendation has been used successfully; however, the dilution factor varies depending on the antibody, tissue, and antigen.

Blocker™ BSA (10X) in TBS (Thermo Scientific™)

Blocker BSA (10X) is purified 10% solution of bovine serum albumin for blocking in western blotting, ELISA, IHC and nucleic acid detection methods.

Compare and view all available blocking buffers

Blocker BSA is a 10% (w/v) solution of high-quality BSA that is useful for saturating excess protein-binding sites on membranes and microplates in immunoassays. It is most frequently diluted 10-fold (to 1% BSA) in 1X PBS or 1X TBS for initial testing. Blocker BSA is usually more effective than nonfat milk blocking buffers for biotin-avidin systems because it contains a single purified protein that is devoid of endogenous biotin.

Related products
Blocker BSA (10X) in PBS

Poly HRP Dilution Buffer (Thermo Scientific™)

Thermo Scientific Pierce Poly-HRP Dilution Buffer is optimized to ensure optimal performance with Poly-HRP Streptavidin.

Features of Poly-HRP Dilution Buffer:

Formulation: 1% biotin-free casein in a PBS buffer solution.
Application: Dilution of Poly-HRP Streptavidin (Product # N200): Gently invert bottle and swirl to mix before use. Do not vortex. Use at full strength. Refer to Poly-HRP Streptavidin Certificate of Analysis for recommended dilution ranges. Dilute Poly-HRP Streptavidin immediately before use.

Related Products
Poly-HRP Streptavidin

cAMP-Screen™ Assay/Lysis Buffer (Invitrogen™)

This Assay⁄Lysis Buffer is suitable for use with the cAMP-Screen® or cAmp-Screen Direct® Immunoassay System.

For Research Use Only. Not for use in diagnostics procedures.

Stop Solution (Invitrogen™)

This stop solution is intended for use as a stop solution in enzyme assays which employ horseradish peroxidase and TMB substrate solution. It is suitable for use in microwell assays such as ELISA.

This product is For Research Use Only. Not intended for any animal or human therapeutic or diagnostic use.

Normal Human Serum (Invitrogen™)

Normal Human Serum Control for IF, ICC, IHC, BLOCK, Ctrl

Assay Buffer (5X) (Invitrogen™)

Assay Buffer (5x) for Antibody Pairs is intended to be used as a:(1) blocking reagent for ELISA plates(2) diluent for ELISA standards and samples(3) diluent for the detection antibody(4) diluent for the HRP conjugate

Application: Antibody pairs (ELISA)

SuperBlock™ (TBS) Blocking Buffer Dry Blend (Thermo Scientific™)

SuperBlock Blocking Buffer Dry Blend contains a single purified glycoprotein that provides incredibly fast and effective blocking for ELISA, IHC, and western blot analysis.

Compare and view all available blocking buffers

Features of SuperBlock Blocking Buffer:
Blocking time—block membranes in 5 to 10 minutes and ELISA plates in 2 minutes
Applications—ELISA, western blotting, IHC; biotin-free for use with streptavidin system
Stability—store buffer in solution at 4°C for one year; store blocked plates dry for up to 12 months

Blocking micro-plates, membranes or tissues with a SuperBlock Buffer yields a high signal-to-noise ratio in most detection systems. The protein-based formulation does not contain any immunoglobulins, albumin, or endogenous biotin, making it compatible in many situations where traditional blocking agents fail. The buffer is especially effective at blocking coated polystyrene microplates (96-well plates) and stabilizing them for drying and storage for later use.

Related products
SuperBlock (PBS) Blocking Buffer
SuperBlock T20 (PBS) Blocking Buffer
SuperBlock (TBS) Blocking Buffer
SuperBlock T20 (TBS) Blocking Buffer

Pierce™ Protein-Free (TBS) Blocking Buffer (Thermo Scientific™)

Pierce Protein-Free Blocking Buffer is a non-protein compound that provides effective blocking for membrane-based and plate-based protein detection methods, resulting in extremely low background. It is supplied in a ready-to-use format.

Compare and view all available blocking buffers

Features of Protein-Free Blocking Buffer:
Protein-free blocker—minimizes or eliminates cross-reactivity associated with protein-based blocking buffers
Applications—western blotting (membranes), ELISA (microplates), and arrays (coated glass slides)
Streptavidin-friendly—free of biotin; no interference with avidin-biotin detection systems
High-performance—optimized and validated in many protein methods to provide high signal-to-noise ratio (i.e., no quenching of specific binding and signal but eliminating nonspecific binding and background)

Traditional blocking buffers contain proteins that can cross-react in certain immunodetection systems, resulting in high background and reduced signal. Pierce Protein-Free Blocking Buffers are devoid of protein while remaining highly effective at blocking plates, membranes, and other surfaces for ELISA, western blotting, glass slide arrays, and other applications.

Related products
Pierce Protein-Free (PBS) Blocking Buffer
Pierce Protein-Free T20 (PBS) Blocking Buffer
Pierce Protein-Free T20 (TBS) Blocking Buffer

ELISA/ELISPOT Coating Buffer Powder (Invitrogen™)

The ELISA/ELISPOT Coating Buffer Powder is designed and tested for use as the working solution for coating the ELISA or ELISPOT capture antibody to the ELISA or ELISPOT plate microwells. This has been tested with all cytokine ELISA and ELISPOT capture antibodies, according to the procedures described in the corresponding protocols.

The eBioscience ELISA/ELISPOT Coating Buffer Powder is a dried powder formulation of phosphate buffered saline. Each packet is reconstituted in 1 Liter of distilled, deionized water, then filtered using a 0.22 um filter. The resulting 1x PBS (pH 7.4) is suitable for use as the ELISA/ELISPOT coating buffer.

Reported Application
ELISA, ELISPOT

Blocker™ Casein in PBS (Thermo Scientific™)

Blocker Casein is a ready-to-use solution of purified casein for blocking steps in western blot, ELISA, IHC, and nucleic acid detection methods. Blocker Casein is 1% (w/v) casein, which corresponds to the optimal concentration for most applications.

Compare and view all available blocking buffers

Features:
Purified casein—single-protein blocking buffer provides fewer chances of cross-reaction with assay components than serum or milk solutions
Easy to use—1% casein solution is ready to use; can be diluted further as needed
Safe—stable, thimerosal-free formulation

Related products
Blocker Casein in TBS

Pierce™ Diethanolamine Substrate Buffer (5X) (Thermo Scientific™)

Thermo Scientific Pierce Diethanolamine Substrate Buffer (5X) include optimized, reliable and convenient stock solutions of diethanolamine for alkaline phosphatase (alk-phos) detection.

Features of Diethanolamine Substrate Buffer (5X):

• Ready-to-use
• Minimize assay-to-assay variability

Diethanolamine Substrate Buffer is used with soluble alkaline phosphatase substrates such as PNPP. Our formulation is convenient, ready-to-use and reduces the possibility of assay-to-assay variability. Diethanolamine Substrate Buffer is sold as 5X concentrate with an optimal, consistent pH. It is stable even at a 1X concentration.

Related Products
Pierce™ Stable Peroxide Substrate Buffer (10X)

eBioscience™ IHC/ICC Blocking Buffer - High Protein (Invitrogen™)

The IHC/ICC Blocking Buffer- High Protein is designed for use in immunohistochemistry and immunocytochemistry protocols which require blocking of non-specific binding sites. This blocking buffer is recommended for tissues and antibodies with high background staining, nuclear antigens, and FFPE tissue. This blocking buffer can be used both in the blocking step and as a diluent for primary and secondary antibodies during antibody incubation steps. The IHC/ICC Blocking Buffer-High Protein is compatible with organic dye-conjugated antibodies as well as unconjugated antibodies that may be used in two and three step staining protocols. This buffer is supplied as a 1X stock solution.

Reported Application
Immunohistochemical Staining, Immunocytochemistry, Immunohistochemical Staining of Frozen Tissue Sections, Immunohistochemical Staining of Formalin-Fixed Paraffin Embedded Tissue Sections

eBioscience™ 20X TBS Wash Buffer for IHC/ICC (Invitrogen™)

The 20X TBS Wash Buffer for IHC/ICC is for use in immunohistochemistry and immunocytochemistry protocols which require washing to remove non-specific binding. This wash buffer is recommended for eFluor™ Nanocrystal conjugated-antibodies following antibody incubation. The TBS Wash Buffer is also compatible with organic dye-conjugated antibodies as well as unconjugated antibodies that may be used in two and three step staining protocols. The buffer is supplied as a 20X stock solution that should be diluted to 1X with distilled water.

Reported Application
Immunohistochemical Staining, Immunocytochemistry

Wash Buffer (25X)

Wash buffer can be used for all ELISA assays.

InstantOne ELISA Wash Buffer (10X) (Invitrogen™)

The InstantOne ELISA Wash Buffer (10X) is developed for use with the InstantOne ELISA Cell Signaling assays. The InstantOne ELISA Wash Buffer is supplied as a 10X concentrate and is used for washing the InstantOne ELISA cell signaling assay microplate. It is a simple mix of buffers, salts, and mild detergent. If washing wells with a microplate washer, use 3x washes with a 10 second mixing cycle.
The InstantOne ELISA Wash Buffer (10X) is included with every InstantOne ELISA sold. This wash buffer is offered additionally as a stand-alone item in cases where experimental procedures and/or automation require much higher volumes of wash buffer.

Reported Application
ELISA

eBioscience™ IHC Antigen Retrieval Solution - High pH (10X) (Invitrogen™)

The IHC Antigen Retrieval Solution- High pH (10X) is designed for use during the heat induced epitope retrieval (HIER) step prior to immunohistochemistry on formalin-fixed paraffin embedded tissue sections. The use of this buffer in combination with heat (often by microwave, water bath, or pressure cooker) has been shown to restore the antigenicity of proteins modified during the formalin fixation of tissue. This buffer is supplied as a 10X stock solution. Dilution of this buffer to 1X using reagent grade water results in a 10 mM Tris, 1 mM EDTA solution, pH 9.0.

Reported Application
Immunohistochemical Staining of Formalin-Fixed Paraffin Embedded Tissue Sections

HRP-Conjugate Diluent/Stabilizer (Invitrogen™)

This product may be used as a conjugate diluent in enzyme immunoassays.

ELISA Blocker Blocking Buffer (Thermo Scientific™)

ELISA Blocker Blocking Buffer is a protein buffer that effectively blocks plate binding sites that remain in polystyrene microplate wells following initial coating steps in ELISA procedures. The ready-to-use buffer is optimized and routinely used for sandwich ELISA procedures involving cytokines, such as many of the Thermo Scientific Pierce ELISA Kits.

Features OF THE ELISA Blocking Buffer:

Size: 1L (sufficient for thirty 96-well plates)
Application: Use as a blocking buffer in ELISA. The buffer is ready to use. No dilution is required.
Instructions for use in an ELISA: Following the incubation with a coating antibody, aspirate the coating antibody from the plate and add 300 µL of ELISA Blocker Blocking Buffer to each well. Cover the plate with a plate sealer and incubate for a minimum of 1 hour at room temperature (22-25°C). Aspirate blocking buffer and proceed with the ELISA procedure or dry the plate for future use.
Plate Drying: Plates should be dried uncovered, at room temperature, for a minimum of 1 hour. For optimal drying, plates should not be stacked and humidity should be at 30-40%. If plates are stacked, or humidity is high, the drying time should be increased. Once drying is complete, seal each plate in a foil pouch with a desiccant. When sealed with a desiccant, plates may be stored at 2-8°C for up to 6 months.

SuperBlock™ T20 (TBS) Blocking Buffer (Thermo Scientific™)

SuperBlock Blocking Buffer is an optimized solution containing a single purified glycoprotein that provides incredibly fast and effective blocking for ELISA, IHC, and western blot analysis.

Compare and view all available blocking buffers

Features of SuperBlock Blocking Buffer:
Blocking time—block membranes in 5 to 10 minutes and ELISA plates in 2 minutes
Applications—ELISA, western blotting, IHC; biotin-free for use with streptavidin system
Stability—store buffer at 4°C for one year; store blocked plates dry for up to 12 months

Blocking micro-plates, membranes or tissues with a SuperBlock Buffer yields a high signal-to-noise ratio in most detection systems. The protein-based formulation does not contain any immunoglobulins, albumin, or endogenous biotin, making it compatible in many situations where traditional blocking agents fail. The buffer is especially effective at blocking coated polystyrene microplates (96-well plates) and stabilizing them for drying and storage for later use.

Related products
SuperBlock (PBS) Blocking Buffer
SuperBlock T20 (PBS) Blocking Buffer
SuperBlock (TBS) Blocking Buffer
SuperBlock (TBS) Blocking Buffer Dry Blend

Pierce™ Fast Wash Buffer, 10X (Thermo Scientific™)

Pierce Fast Wash Buffer, 10X, for use with Pierce Fast Blocking Buffer.

Related Products
Pierce™ Fast Blocking Buffer

Peroxidase Suppressor (Thermo Scientific™)

Thermo Scientific Pierce Peroxidase Suppressor is a stable, easy-to-use inhibitor of endogenous peroxidase activity from cells and tissues to reduce background signal in HRP-based immunohistochemistry applications.

Features of Peroxidase Suppressor:

• Stable
• One component
• Ready-to-use
• Effectively inhibits peroxidase activity without interfering with antigen-antibody
interactions

This peroxidase suppressor is optimized for immunohistochemical applications. The Peroxidase Suppressor is a stable, easy-to-use inhibitor of endogenous peroxidase activity. This proprietary formulation is the most effective peroxidase inhibitor available. The immunoperoxidase method is a commonly used detection method for immunostaining of cells and tissues. However, the analysis often is complicated by the presence of endogenous peroxidase and "pseudoperoxidase" activity in the cells and tissues. This presence results in nonspecific staining when a substrate such as diaminobenzidine (DAB) is present. Nonspecific staining is difficult to distinguish from the immunochemical marker, making it difficult to distinguish the final location of the antigen of interest. The typical method of inhibiting endogenous peroxidase activity involves hydrogen peroxide or hydrogen peroxide in methanol. The peroxidase suppressor inhibits peroxidase activity even more effectively than the method using hydrogen peroxide in methanol. Plus, the Peroxidase Suppressor does not affect antibody activity (see figure). Peroxidase Suppressor also can be used on blots of whole cell supernatant prior to the addition of the horseradish peroxidase (HRP) marker.

Pierce™ Protein-Free T20 (PBS) Blocking Buffer (Thermo Scientific™)

Pierce Protein-Free Blocking Buffer is a non-protein compound that provides effective blocking for membrane-based and plate-based protein detection methods, resulting in extremely low background. It is supplied in a ready-to-use format.

Compare and view all available blocking buffers

Features of Protein-Free Blocking Buffer:
Protein-free blocker—minimizes or eliminates cross-reactivity associated with protein-based blocking buffers
Applications—western blotting (membranes), ELISA (microplates), and arrays (coated glass slides)
Streptavidin-friendly—free of biotin; no interference with avidin-biotin detection systems
High-performance—optimized and validated in many protein methods to provide high signal-to-noise ratio (i.e., no quenching of specific binding and signal but eliminating nonspecific binding and background)

Traditional blocking buffers contain proteins that can cross-react in certain immunodetection systems, resulting in high background and reduced signal. Pierce Protein-Free Blocking Buffers are devoid of protein while remaining highly effective at blocking plates, membranes, and other surfaces for ELISA, western blotting, glass slide arrays, and other applications.

Related products
Pierce Protein-Free (PBS) Blocking Buffer
Pierce Protein-Free (TBS) Blocking Buffer
Pierce Protein-Free T20 (TBS) Blocking Buffer

Stop Solution for TMB Substrates (Thermo Scientific™)

Stop Solution is 0.16M sulfuric acid for use with the ELISA substrate 3,3’,5,5’ - tetramethylbenzidine (TMB). In the presence of horseradish peroxidase (HRP) enzyme conjugates, TMB and peroxide react to produce a blue byproduct having maximum absorbance at 605nm. The color intensity is proportional to the amount of HRP activity, which in turn is related to the levels of target analyte in an optimized ELISA procedure. Addition of sulfuric acid stop solution changes the color to yellow (absorbance maximum at 450nm), stabilizing the color development to enable accurate measurement of the intensity at 450nm using a spectrophotometer or plate reader.

Features of Stop Solution:

Size: 55 mL (sufficient for about five 96-well microplates)
Storage: Shipped at ambient temperature. Store at room temperature or 2-8°C.
Application: ELISA: Following TMB incubation, add an amount of stop solution equal to the amount of TMB substrate added to each well of the ELISA plate (typically 50–100 µL per well). Use at full strength.

Coating Buffer A

The Invitrogen Coating Buffer A is intended for use with Invitrogen Antibody Pairs as part of the recommended assay procedure.

Ethylene Glycol (Thermo Scientific™)

Thermo Scientific Pierce Ethylene Glycol Solution provides exceptional antifreeze protection and storage stability for antibody-enzyme conjugates because it is purified to remove impurities commonly found traditional glycerol stocks.

Features of Ethylene Glycol:

• Specially purified to remove impurities such as aldehydes, peroxides, iron and UV absorbing hydrocarbons
• Suitable for enzyme storage without the worry of losing enzymatic activity
• Stable for months

This product is a 50% (w/v) aqueous solution of highly purified ethylene glycol. When mixed in equal volume with purified protein samples, such as primary antibodies, the solution stabilizes and maintains the mixture as a liquid during freezer storage (-20°). Ethylene glycol is a suitable alternative to glycerol for most protein-storage applications. In fact, this preparation of ethylene glycol is devoid of various common glycerol impurities and potiential degradation products that are damaging to certain enzymes.

Normal Goat Serum (Invitrogen™)

Normal Goat Serum Control for IF, ICC, IHC, BLOCK, Ctrl

Blocker™ Casein in TBS (Thermo Scientific™)

Blocker Casein is a ready-to-use solution of purified casein for blocking steps in western blot, ELISA, IHC, and nucleic acid detection methods. Blocker Casein is 1% (w/v) casein, which corresponds to the optimal concentration for most applications.

Compare and view all available blocking buffers

Features:
Purified casein—single-protein blocking buffer provides fewer chances of cross-reaction with assay components than serum or milk solutions
Easy to use—1% casein solution is ready to use; can be diluted further as needed
Safe—stable, thimerosal-free formulation

Related products
Blocker Casein in PBS

CellVue Diluent C (For CellVue™ Cell Labeling Kits) (Invitrogen™)

Diluent C is the Buffer required for the dilution of the dyes in the CellVue™ Cell Labeling Kits. Please refer to the specific labeling kit for instructions of use.

Reported Application
Flow Cytometric Analysis, Microscopy

Poly-HRP Dilution Buffer (Thermo Scientific™)

Thermo Scientific Pierce Poly-HRP Dilution Buffer is optimized to ensure optimal performance with Poly-HRP Streptavidin.

Features of Poly-HRP Dilution Buffer:

Formulation: 1% biotin-free casein in a PBS buffer solution.
Application: Dilution of Poly-HRP Streptavidin (Product # N200): Gently invert bottle and swirl to mix before use. Do not vortex. Use at full strength. Refer to Poly-HRP Streptavidin Certificate of Analysis for recommended dilution ranges. Dilute Poly-HRP Streptavidin immediately before use.

Related Products
Poly-HRP Streptavidin

Buffer Kit for Antibody Pairs (Invitrogen™)

This Buffer Kit for Antibody Pairs is for use with Invitrogen Antibody Pairs. This Kit provides sufficient materials for 10 ELISA plates.

StartingBlock™ T20 (TBS) Blocking Buffer (Thermo Scientific™)

StartingBlock Blocking Buffer is a single purified protein for fast blocking of western blots and ELISA assays. It provides broad compatibility with a wide range of antibodies, antibody combinations, and other protein probing and assay systems. StartingBlock is available in PBS and TBS with and without Tween20.

Compare and view all available blocking buffers

Features of StartingBlock Blocking Buffers:
Strip and reprobe without reblocking—blots stay blocked even after stripping with Thermo Scientific Restore Stripping Buffer (Cat. No. 21059)
Compatible with many detection systems—western blot, ELISA, and IHC with antibody or avidin/biotin probes (blocker is serum and biotin-free)
Short blocking times—less than 15 minutes for nitrocellulose or PVDF membranes, almost instantaneous for polystyrene microplate wells
Biotin- and serum protein-free formulation

Related products
StartingBlock (PBS) Blocking Buffer
StartingBlock T20 (PBS) Blocking Buffer
StartingBlock (TBS) Blocking Buffer

SuperBlock™ (TBS) Blocking Buffer (Thermo Scientific™)

SuperBlock Blocking Buffer is an optimized solution containing a single purified glycoprotein that provides incredibly fast and effective blocking for ELISA, IHC, and western blot analysis.

Compare and view all available blocking buffers

Features of SuperBlock Blocking Buffer:
Blocking time—block membranes in 5 to 10 minutes and ELISA plates in 2 minutes
Applications—ELISA, western blotting, IHC; biotin-free for use with streptavidin system
Stability—store buffer at 4°C for one year; store blocked plates dry for up to 12 months

Blocking micro-plates, membranes or tissues with a SuperBlock Buffer yields a high signal-to-noise ratio in most detection systems. The protein-based formulation does not contain any immunoglobulins, albumin, or endogenous biotin, making it compatible in many situations where traditional blocking agents fail. The buffer is especially effective at blocking coated polystyrene microplates (96-well plates) and stabilizing them for drying and storage for later use.

Related products
SuperBlock (PBS) Blocking Buffer
SuperBlock T20 (PBS) Blocking Buffer
SuperBlock T20 (TBS) Blocking Buffer
SuperBlock (TBS) Blocking Buffer Dry Blend

Support Pack Plus (Invitrogen™)

Buffer pack for 10 plates (plates included)

Reactivity/Species
Human, Mouse, Rat

Reported Application
ELISA

Protein Stabilizing Cocktail (Thermo Scientific™)

The Thermo Scientific Protein Stabilizing Cocktail is a versatile stabilizing solution that increases the shelf-life of purified or partially purified proteins during routine storage.

Features of the Protein Stabilizing Cocktail:

• Stabilizes most enzymes and other proteins significantly better than ordinary buffers
• Protect proteins from environmental stresses
• Does not destabilize biomolecules in downstream assays
• Components are low molecular weight and fully dialyzable
• Low-viscosity reagent is easier to pipette than 50% glycerol
• Protein classes tested include kinases, phosphatases, peroxidases, restriction enzymes, luciferases, cytokines and antibodies

This proprietary formulation of low-molecular weight, naturally occurring molecules helps protect proteins from environmental stresses that can otherwise lead to enzyme inactivation, aggregation and freeze-thaw damage. The Protein Stabilizing Cocktail is provided as an easily pipettable, buffered 4X concentrate. Solutions of enzymes and other proteins to which the cocktail has been added may be refrigerated or frozen for storage without losing their activity or function. Although the degree of stabilization is protein-specific, the cocktail significantly stabilizes most proteins compared with conventional buffer alone. The Protein Stabilizing Cocktail is nontoxic and does not destabilize biomolecules; however, all cocktail components can be removed by dialysis or desalting before use in downstream assays, if desired.

eBioscience™ IHC /ICC Blocking Buffer - Low Protein (Invitrogen™)

The IHC/ICC Blocking Buffer- Low Protein is designed for use in immunohistochemistry and immunocytochemistry protocols which require blocking of non-specific binding sites. This blocking buffer is recommended for tissues and antibodies with average levels of background staining. This blocking buffer can be used both in the blocking step and as a diluent for unconjugated antibodies and organic dye-conjugated antibodies during the antibody incubation step. This buffer is supplied as a 1X stock solution containing sodium azide.

Reported Application
Immunohistochemical Staining, Immunocytochemistry, Immunohistochemical Staining of Frozen Tissue Sections, Immunohistochemical Staining of Formalin-Fixed Paraffin Embedded Tissue Sections

SEA BLOCK Blocking Buffer (Thermo Scientific™)

Thermo Scientific SEA BLOCK Blocking Buffer is steelhead salmon serum in PBS that is especially useful as a blocking agent in IHC and other detection methods involving mammalian samples.

Features of SEA BLOCK Blocking Buffer:

Non-mammalian—fish proteins are less likely to have specific binding interactions with antibodies and other mammalian proteins present in typical methods
Convenient—filtered and stabilized in PBS for compatibility with most assay systems
Easy to use—can be used as supplied or diluted up to 10-fold as needed
Flexible—may be used for many different applications, including as a diluent for antibodies

Because SEA BLOCK Blocking Buffer is fish serum, it is effective in stabilizing solutions and samples for antibody-binding interactions while at the same time minimizing the possibility of cross-reaction with mammalian sample components. When normal sera cause background in immunohistochemistry (IHC), try this product. The product is also especially effective in various cellular imaging protocols based on visible and near-infrared fluorescence detection.

Fish serum has several advantages over typical blocking buffers. Because salmon is phylogenetically distant from mammals, which are the source of antibodies and samples used in most experiments, its serum proteins are less likely to have specific binding interactions with proteins used in typical cell biology experiments. Because SEA BLOCK Blocking Buffer is fish serum, it is effective in stabilizing solutions and samples for antibody-binding interactions. When normal sera cause background in IHC experiments, SEA BLOCK Blocking Buffer may correct the problem.

SEA BLOCK Blocking Buffer is particularly effective in applications involving fluorescence imaging. The blocker has been used to decrease background and increase signal-to-noise ratios with near-IR fluorescent probes and is validated for use with the LI-COR Odyssey™ Infrared Imaging System.

Enhancer Solution (Invitrogen™)

The InstantOne ELISA Enhancer Solution is a supplement added to the 5X Cell Lysis Buffer (Cat. No. IOCLB1) to yield the Cell Lysis Mix solution that is applied to cultured cells or tissues prior to running the assays. The 1X Cell Lysis Mix is prepared by simply diluting Cell Lysis Mix (5X) (a mixture of the Cell Lysis Buffer (5X) and the Enhancer Solution) 5-fold with deionized water. This buffer is used to lyse cells after the removal of culture medium, and is typically used to lyse adherent cells or non-adherent cells that have been harvested by centrifugation. Lysis Mix should be used as the diluent for any dilution of cellular lysates that are required.

Reported Application
ELISA

eBioscience™ IHC Antigen Retrieval Solution - Low pH (10X) (Invitrogen™)

The IHC Antigen Retrieval Solution- Low pH (10X) is designed for use during the heat induced epitope retrieval (HIER) step prior to immunohistochemistry on formalin-fixed paraffin embedded tissue sections. The use of this buffer in combination with heat (often by microwave, water bath, or pressure cooker) has been shown to restore the antigenicity of proteins modified during the formalin fixation of tissue. This buffer is supplied as a 10X stock solution. Dilution of this buffer to 1X using reagent grade water results in a 10 mM Sodium Citrate solution, pH 6.0.

Reported Application
Immunohistochemical Staining of Formalin-Fixed Paraffin Embedded Tissue Sections

Pierce™ Peroxidase Conjugate Stabilizer (Thermo Scientific™)

Thermo Scientific Pierce Peroxidase Conjugate Stabilizer is an antifreeze solution for storing freezer aliquots and stocks of antibodies and other HRP-conjugates in liquid form so they can be pipetted for use without thawing.

Features of Peroxidase Conjugate Stabilizer:

• Provides a buffered anti-freeze environment for enzyme conjugated antibodies and proteins
• Contains high-purity ethylene glycol, which maintains a liquid, low viscosity solution at -20°C
• Contains preservatives to prevent anti-microbial growth during long-term storage
• No aliquoting of conjugate is necessary and sampling is convenient

Pierce Peroxidase Conjugate Stabilizer is a storage solution for peroxidase-conjugated antibodies, streptavidin and other proteins (HRP conjugates). Mixing the Stabilizer in 2:1 or 1:1 ratio with HRP conjugate solutions (usually at least 1 mg/mL) produces a stabilized conjugate stock solution that remains a liquid at -20°C. This allows the conjugate to be pipetted directly from the sub-zero temperature condition, eliminating damaging freeze-thaw cycles. The highly purified solution is free of oxidizing agents and other contaminants that can harm enzyme activity, ensuring that stock solutions can be stored for months without significant loss of activity.

Coating Buffer B

The Invitrogen Coating Buffer B is intended for use with Invitrogen Antibody Pairs as part of the recommended assay procedure.

Normal Rabbit Serum (Invitrogen™)

Normal Rabbit Serum Control for BLOCK, Ctrl

Normal Porcine Serum (Invitrogen™)

Normal Porcine Serum Control for IF, ICC, IHC, BLOCK, Ctrl

Assay Buffer (10X) (Invitrogen™)

This Assay Buffer is used in immunoassays and in Western and Southern blotting for alkaline phosphatase Tropix® substrate conjugates.

For Research Use Only. Not for use in diagnostics procedures.