TMB-D Blotting - Ready-to-use (RTU)

Cat. No.: T494241

GRADE & PURITY Ready-to-use (RTU)

Storage

Store at 2-8°C,Protected from light

Shipped In

Wet ice

Panoramica

TMB (3, 3', 5, 5'-tetramethylbenzidine) is a chromogenic substrate for Horseradish Peroxidase (HRP). TMB produces a deep blue color during the enzymatic degradation of hydrogen peroxide by HRP.

TMB-D Blotting liquid ready-to-use substrate is a highly active and stable blotting substrate utilized for measuring HRP probe activity. A stable blue precipitate is formed at the reaction site.

The substrate does not contain NMP (1-methyl2-pyrrolidone) making it REACH Restricted Substances List Annex XVII compliant, while ensuring maximal safety during use, and minimal negative environmental impact.

Product Characteristics 

TMB (3, 3', 5, 5'-tetramethylbenzidine) is a chromogenic substrate for Horseradish Peroxidase (HRP). TMB produces a deep blue color during the enzymatic degradation of hydrogen peroxide by HRP.

TMB-D Blotting liquid ready-to-use substrate is a highly active and stable blotting substrate utilized for measuring HRP probe activity. A stable blue precipitate is formed at the reaction site. 

The substrate does not contain NMP (1-methyl-2- pyrrolidone) making it REACH Restricted Substances List Annex XVII compliant, while ensuring maximal safety during use, and minimal waste problems after use.

Composition & Properties 

Ready-to-use substrate: Includes substrate buffer and hydrogen peroxide. No other reagents should be added.

Working Procedure 

The following procedure is applicable to nitrocellulose membranes. The procedure must be optimized for other membranes.

1.The desired amount of substrate is poured into a sealed container and allowed to reach room temperature, in the dark, before use. 

2.After the last incubation with HRP-labelled Streptavidin or HRP-labelled secondary antibody it is recommended to wash the membrane in a 0.1 M Tris buffer pH 7.4.

3.Shake off the excess buffer and incubate the membrane in the TMB-D Blotting solution for 10 minutes. 

4.Wash the membrane in distilled water and allow it to dry. 

5.The site of positive reaction will appear light blue with no or very little background staining.

Tips & Tricks 

• The membrane can be blocked with Kementec’s Synthetic Blocking Buffer for Blotting, (cat. no. S494457). 

• For long-term preservation of the results, the membranes must be stored in the dark.

Handling & Storage 

• Store solution at 2-8⁰C in the dark. 

• Avoid exposure to light, heat and contamination with metal ions or peroxidase. 

• Re-dispense only into bottles made of High-Density Polyethylene (HDPE), amber color. Dispensing guidelines are available upon request.

Specifications

Specifiche e purezza

Ready-to-use (RTU)

Condizioni di conservazione di stoccaggio

Store at 2-8°C,Protected from light

Spedito in

Wet ice

Questo prodotto richiede spedizione a catena fredda. I servizi di terra e altri servizi economici non sono disponibili.

Application Protocols

Tested applications, recommended dilutions, incubation times, and specific membrane procedures are not specified for this item; refer to CoA/Spec Sheet and SDS.

Note: Although general Western/dot blot workflows are widely established for TMB-based substrates, only manufacturer-validated protocols should be cited as product-specific. In the absence of such data, users should optimize empirically with their membranes, blocking reagents, and HRP conjugate concentrations.

Biological Roles

This product is a chemical detection reagent for laboratory immunoassays and does not possess intrinsic biological roles in living systems.

General/literature context related to its use:

• Enzymatic reporter system: Horseradish peroxidase (HRP) is used as an enzyme label on antibodies or streptavidin. In the presence of hydrogen peroxide, HRP catalyzes the one-/two-electron oxidation of TMB, yielding a colored product localized where the HRP conjugate is bound.
• Signal generation: On membranes, the oxidized TMB forms an insoluble blue precipitate, enabling visual detection and densitometric quantification of immobilized proteins or nucleic acids.
• Specificity derives from the immunochemical interaction (antigen–antibody or biotin–streptavidin), not from TMB itself. TMB acts solely as a redox indicator substrate in the peroxidase cycle.

Considerations for biological samples (best practice):

• Endogenous peroxidase activity (e.g., from heme proteins) is typically not a concern on Western membranes but may cause background in tissue/cell-based formats; blocking or using alternative detection is advised in such cases.
• For quantitative comparisons, normalize sample loading and verify linear response with internal standards; the chromogenic endpoint is less linear than chemiluminescence at very high signal levels.

Buffer Applications

Not typically applicable. TMB-D Blotting is a detection substrate rather than a buffering agent.

• Practical note: Use with standard blotting buffers (e.g., TBS or PBS for washes). Avoid buffers containing azide during antibody incubations with HRP conjugates, as azide inhibits peroxidases.
• Preparation details, buffer pH, and composition of this product are not specified for this item; refer to CoA/Spec Sheet.

Green Alternatives

Context: TMB-D Blotting is an aqueous, ready-to-use HRP substrate. From a green chemistry perspective, considerations include hazard profile, waste minimization, and energy inputs.

• Greener aspects (general):

  • Water-based formulation minimizes VOCs and flammability compared with organic dye-based detection.
  • Room-temperature operation reduces energy consumption.

• Comparisons (general; not item-specific claims):

  • DAB (3,3′-diaminobenzidine): Classified with higher toxicity concerns; disposal can be more restrictive. TMB is generally preferred when feasible from a hazard standpoint.
  • ECL (luminol/hydrogen peroxide enhancers): Often offers higher sensitivity, reducing antibody and sample use (source reduction). However, signal is transient and may require repeat exposures.
  • AEC (3-amino-9-ethylcarbazole): Organic solvent handling often required and precipitate is alcohol-soluble; less favorable for sustainability.

• Practical green tips:

  • Right-size aliquots to minimize expired waste; keep containers closed and protected from light to extend shelf life.
  • Use minimal development volumes sufficient to cover the membrane; collect spent substrate separately for appropriate disposal.
  • Standardize development to avoid repeats; this reduces reagent consumption and waste.

Small comparison table (general):

• TMB (precipitating, aqueous): moderate hazard, permanent record, low VOCs.
• DAB: higher hazard classification, brown precipitate, stricter disposal.
• ECL: very high sensitivity, low chemical mass used per blot, requires imaging system.

Pharmaceutical Uses

Not applicable. TMB-D Blotting is intended for research laboratory detection workflows (e.g., Western/dot blots) and is not used as a pharmaceutical excipient or in clinical formulations.

• Research Use Only statement: For research use only (provided). Not for diagnostic or therapeutic use.
• Regulatory/pharmacopeial status: Not specified for this item; refer to CoA/Spec Sheet if any compliance information is available for ancillary laboratory reagents.

Physical Properties

Item-specific properties (this product):

• Appearance: Not specified for this item; refer to CoA/Spec Sheet.
• Physical state, pH, viscosity, and composition: Not specified for this item; refer to CoA/Spec Sheet.
• Molecular weight, molecular formula: Not specified for this item; refer to CoA/Spec Sheet.
• Refractive index, density, UV cutoffs: Not specified for this item; refer to CoA/Spec Sheet.
• Solubility: This is generally supplied as an aqueous, ready-to-use solution for blotting, but exact formulation/solubility is not specified for this item; refer to CoA/Spec Sheet.

General/literature context (for TMB chromogenic systems; not item-specific specifications):

• TMB is only sparingly soluble in water but soluble in organic solvents; in practice, blotting substrates contain TMB in a stabilized aqueous buffer with H2O2 and proprietary stabilizers.
• Oxidized TMB in solution shows absorbance maxima around 370 nm and 650 nm (literature), while on membranes it forms an insoluble blue precipitate that localizes bands/spots.
• TMB-based substrates are light- and air-sensitive (susceptible to slow background oxidation), motivating storage at 2–8°C and protection from light.

Practical implications:

• Use dedicated, clean plasticware and avoid trace metal contamination, which can catalyze non-enzymatic oxidation and increase background.
• Equilibrate to room temperature before use to ensure uniform color development; avoid prolonged exposure to intense light.

Quality and Grades

Item-specific grade/purity: Not specified for this item; refer to CoA/Spec Sheet.

What “blotting-grade TMB substrate” typically implies (general/literature context):

• Low-background, membrane-optimized formulation: balanced H2O2 concentration and stabilizers to minimize non-enzymatic color formation and provide sharp band localization on nitrocellulose/PVDF.
• Lot-to-lot consistency: activity is often qualified by developing a standard HRP ladder/dot blot under fixed conditions to verify signal-to-background and dynamic range.
• Photostability controls: filled under low-light; containers are often amber to reduce photodegradation.

Quality attributes a professional lab may verify upon receipt (recommended practices; not item specs):

• Blank absorbance baseline at 370/650 nm vs water to gauge background.
• Development kinetics with a standard HRP-conjugate at multiple dilutions to confirm sensitivity and linear range.
• Membrane compatibility and wash-off resistance of precipitated dye.

Stabilizers and preservatives:

• Specific stabilizers/preservatives (e.g., proprietary chelators, antimicrobial agents) are not specified for this item; refer to CoA/Spec Sheet for detailed composition if disclosed.

Documentation:

• For regulated workflows, retain the lot CoA and SDS, and, if applicable, internal qualification data linking lot number to assay performance.

Reaction and Applications

Primary application: HRP-mediated chromogenic detection in Western and dot/slot blotting.

• Reaction principle (general):

  • HRP uses H2O2 to oxidize TMB to a diimine radical cation. On membranes, oxidation leads to an insoluble blue product that deposits at the enzyme location, revealing bands/spots.
  • The precipitated product can be scanned for densitometry (typically at 600–650 nm reflectance).

• Workflow placement:

  • After transfer and blocking, membranes incubated with HRP-labeled secondary (or primary) antibody are developed by brief exposure to the substrate until desired intensity is reached, then rinsed with water or buffer to stop the reaction.

• Practical tips (general/best practice):

  • Develop under subdued light; use fresh, room-temperature substrate for uniform kinetics.
  • Avoid metal tweezers contact with active solution; use plastic forceps to reduce nonspecific oxidation.
  • Monitor development continuously; overdevelopment increases background and can obscure fine bands.
  • For semi-quantitation, stay within the linear range by standardizing antibody dilutions and exposure time; include a reference ladder or internal standard.

• Downstream handling:

  • Dry membranes flat for archiving; the blue precipitate is generally stable but can fade under prolonged strong light.
  • If stripping/reprobing is required, note that precipitated chromogen can hinder complete stripping; consider chemiluminescence for membranes intended for multiple probings.

Item-specific application testing data: Not specified for this item; refer to CoA/Spec Sheet.

Reaction Conditions

Item-specific reaction parameters are not specified; refer to CoA/Spec Sheet. The following guidance reflects general, literature-based practice for HRP/TMB development on membranes and should be adapted empirically.

Typical conditions (general):

• Temperature: Room temperature (20–25°C).
• Light: Subdued light to minimize non-enzymatic background.
• Development time: Commonly 1–10 minutes, monitoring visually until bands reach desired intensity.
• Stopping: Rinse thoroughly with distilled water or buffer to halt further color development.

Membrane and buffer environment:

• Membranes: Nitrocellulose or PVDF; ensure complete wetting and adequate blocking to reduce background.
• Wash buffers: TBS or PBS with 0.05% Tween-20 are standard; final washes without detergent may reduce edge effects before development.

Performance considerations:

• Dynamic range: Chromogenic endpoints are semi-quantitative; maintain antibody and HRP conjugate within the linear response window.
• Background control: Ensure stringent washing; minimize metal contamination; avoid sodium azide with HRP.

Waste and cleanup:

• Collect spent substrate in appropriate waste per institutional and local regulations. Rinse equipment with water promptly to prevent staining.

Note: Exact composition, pH, and optimal exposure for this specific product are not specified and should be determined experimentally.

Safety and Handling

Item-specific hazard information (from provided data):

• GHS classification: Not specified for this item; refer to SDS.
• Signal word: Not specified for this item; refer to SDS.
• H-statements and pictograms: Not specified for this item; refer to SDS.

General safety considerations for TMB-based HRP substrates (literature/good practice; not item-specific):

• TMB solutions may cause skin/eye irritation. Peroxide-containing formulations are oxidizing; avoid contact with reducing agents and transition metals.
• Light- and air-sensitive: store tightly closed, protected from light, to minimize background oxidation and pressure build-up from O2 ingress is not expected but minimize headspace exposure.

Personal protective equipment (PPE):

• Wear lab coat, safety glasses, and nitrile gloves. Work in a well-ventilated area or fume hood when handling bulk quantities.

Incompatibilities and handling tips:

• Avoid contamination with HRP, peroxidase-like heme proteins, or metal dusts that can trigger premature color formation.
• Use only clean, inert plastics or glass; thoroughly rinse vessels of bleach (hypochlorite) before use, as residual oxidants can elevate background.

First-aid overview (refer to SDS for authoritative guidance):

• Skin/eye contact: Rinse with water for 15 minutes; remove contaminated clothing. Seek medical attention if irritation persists.
• Ingestion/inhalation: Rinse mouth, move to fresh air, obtain medical attention if symptoms occur.

Fire and spill response:

• Most aqueous substrates are not flammable; however, treat spills as chemical spills—absorb with inert material and dispose per institutional guidelines.

Solvent Selection

This product is a ready-to-use aqueous detection reagent, not a general-purpose solvent.

• Polarity and medium: Water-based buffer system designed for HRP-catalyzed chromogenic development on membranes. Exact buffer composition is not specified for this item; refer to CoA/Spec Sheet.
• Miscibility: Readily miscible with water; avoid mixing with organic solvents (methanol, ethanol) during development as they can affect precipitation and band morphology.
• Membrane compatibility (general):
  • Nitrocellulose: Rapid, high-contrast deposition of insoluble blue product.
  • PVDF: Compatible; pre-wetting and blocking quality strongly influence background.
• Use scenarios:
  • Choose chromogenic TMB for rapid visual endpoint detection, archival stability, and densitometry without specialized imaging equipment.
  • Prefer chemiluminescent substrates (ECL) for maximal sensitivity/linear range when imaging equipment is available.

Small comparison (general; not item-specific specifications):

• TMB (chromogenic, precipitating): convenient, visible, mid-to-high sensitivity, permanent record.
• DAB (diaminobenzidine): brown precipitate; generally more hazardous/toxic; used more often in histology.
• ECL (luminol-based): highest sensitivity and broad linearity; requires imager; signal is transient.

Storage and Reconstitution

Item-specific storage conditions (provided):

• Store at 2–8°C, protected from light.
• Shipped on wet ice.

Reconstitution:

• Not specified for this item; refer to CoA/Spec Sheet. Many blotting substrates are supplied ready-to-use; if concentrates or multi-component systems are supplied, follow the manufacturer’s mixing instructions under low light.

Handling and aliquoting (best practice):

• Allow to equilibrate to room temperature before opening to prevent condensation ingress.
• Minimize light exposure; keep container tightly closed when not in use. If frequent use is expected, prepare working aliquots in amber microtubes to reduce repeated light/air exposure of the stock.
• Do not freeze unless the CoA/Spec Sheet explicitly permits; freeze–thaw can reduce activity and increase background.

Shelf life:

• Not specified for this item; refer to CoA/Spec Sheet. Discard if strong background color develops in the bottle or if performance deviates from prior lots under identical conditions.

Structure and Identity

Brief description: TMB‑D Blotting is a ready-to-use, light-sensitive chromogenic substrate system for horseradish peroxidase (HRP) detection on membranes (e.g., nitrocellulose, PVDF) in blotting workflows.

• Item-specific identifiers:

  • SKU: T494241
  • Product name: TMB-D Blotting
  • CAS: Not specified for this item; refer to CoA/Spec Sheet.
  • InChIKey: Not specified for this item; refer to CoA/Spec Sheet.
  • SMILES: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular formula / MW: Not specified for this item; refer to CoA/Spec Sheet.

• Functional class and structural features (general/literature context):

  • The active chromogen in TMB-type systems is typically 3,3′,5,5′-tetramethylbenzidine (TMB), an aromatic diamine that undergoes HRP/H2O2-mediated two-electron oxidation to a diimine radical cation, forming an intense blue product on membranes.
  • TMB (literature):
    • Molecular formula: C16H20N2
    • SMILES: CC1=C(C(C)=C(N)C(C)=C1N)C
    • InChIKey: KWKAKUADMBYYCI-UHFFFAOYSA-N
  • Structural description (general): para-disubstituted benzidine core with four methyl groups (two per ring) and two primary anilines; readily oxidizable.

• 2D structure in words (general): Two phenyl rings linked via a single C–C bond (benzidine scaffold), each ring bearing amino and methyl substituents in a symmetrical 3,5-dimethyl pattern, enabling conjugation and color development upon oxidation.

Note: The above identifiers for TMB are literature/general values for the chromogen class; the exact composition of this formulated “TMB-D Blotting” product is not specified in the provided data.

Synthetic Utility

Not typically applicable. TMB-D Blotting is a formulated detection reagent for immunoassays, not a building block or reagent for preparative organic synthesis.

General chemical note (contextual, not item-specific):

• The underlying chromogen (TMB) is an easily oxidized aromatic diamine. While such compounds can, in principle, participate in diazotization or coupling chemistry, formulated HRP substrates are not used for synthetic transformations due to stabilizers, water content, and safety considerations.

Recommendation:

• For synthetic needs involving aromatic diamines or redox indicators, source neat, well-characterized chemicals with specified purity and impurity profiles rather than a prepared detection substrate.

Target Specificity

Not applicable. This product is a chromogenic substrate for HRP detection and does not have antigen/epitope specificity, clone information, or isotype characteristics.

• Species reactivity, antigen name, clone, and isotype: Not applicable.
• Use with: Compatible with HRP-conjugated antibodies or HRP–streptavidin in blotting workflows.