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Easy-Titer™ Mouse IgG Assay Kit (Thermo Scientific™)

The Thermo Scientific Easy-Titer Mouse IgG Assay Kit includes antibody-sensitized microspheres to measure the specific concentration of antibodies by an easy and rapid microagglutination technique using standard microplates and UV-Vis plate reader (spectrophotometer). This kit is specific for mouse IgG and, unlike total protein assays, can specifically measure the concentration of target antibody in samples (e.g., serum, plasma, culture supernatant) that contain other proteins. It is sensitive, requiring very small sample volumes. Antibody concentration is determined from the assay response (absorbance) by comparison to a standard curve prepared using dilutions of a known antibody sample (sold separately).

General features of Easy-Titer Antibody Assay Kits:

Antibody-based specificity—measure concentration of target antibody in a sample, not just total protein; no need to purify antibody to assess its concentration
Faster and easier than ELISA—three-component, homogenous assay; 10 minutes total incubation time
No special equipment needed—uses standard vortex mixer, pipetter, 96-well microplate, plate shaker and reader (measure absorbance at 340nm or 400nm)
Sensitive—assay range (standard curve) 8 to 500 ng/mL; use sample at 15 to 300 ng/mL for optimal results
Reproducible—coefficient of variation < 5%; error depends on dilution and pipetting technique
Antibody standards sold separately—see product list for suggested products; use any antibody standard with proper target identity and known concentration (greater than 10 µg/mL)
Kits for five popular targets—choose a kit specific for a particular species and class of immunoglobulin; no cross-reaction with other species and classes of the target antibody

Easy-Titer Assay Kits detect and measure specific target antibodies using agglutination of microspheres that are coated ("sensitized") with the specific anti-IgG or IgM polyclonal antibodies. In the appropriate aqueous buffer (supplied in kit), the monodispersed antibody-coated microspheres (> 1 µM diameter) have highest absorptivity (λ-max) to incident light having a wavelength (340nm) that is equal to approximately half their diameter. When sample is added, two or more microspheres bind to each antibody target via their coated specific polyclonal antibodies, and this agglutination into effectively larger apparent spheres results in proportional decrease in absorptivity (lower absorbance).

Typical microagglutination assays depend on a change in light-scattering and corresponding change in transmittance, to which absorbance is inversely related. Easy-Titer Assay Kits use a special dilution buffer whose refractive index eliminates the effect of light-scattering on the monodispersed microspheres for the measurement wavelength used. Because of this, the final 10- to 20-fold dilution of the sample for use in the assay must be done using the Dilution Buffer supplied in the kit.

Easy-Titer Antibody Assays are faster and easier than ELISA:
• Prepare standards (5 to 500 ng/mL) by diluting purified antibody in Kit Dilution Buffer.
• Prepare samples by diluting in Dilution Buffer to within assay range (8 to 500 ng/mL).
• Vortex vial of microsphere beads to create homogeneous suspension.
• Pipette 20 µL of bead suspension and 20 µL of each sample and standard into 96-well microplate wells.
• Incubate microplate for 5 minutes with vigorous mixing.
• Add 100 µL of Kit Blocking Reagent.
• Incubate microplate for 5 minutes with vigorous mixing.
• Measure absorbance on standard plate reader (340nm or 405nm).
• Plot standard curve and interpolate samples to determine concentration.

Related Products
Easy-Titer™ Rabbit IgG Assay Kit
Easy-Titer™ Human IgG (H+L) Assay Kit
Easy-Titer™ Human IgG (gamma chain) Assay Kit
Easy-Titer™ Human IgM Assay Kit

Pierce™ Streptavidin Coated Plate IP Kit (Thermo Scientific™)

The Thermo Scientific Pierce Streptavidin Coated Plate IP Kit uses coated streptavidin microplates to perform immunoprecipitation assays in 96-well plates without resins, beads, centrifugation or magnets.

Pierce Coated Plate IP Kits enable rapid immunoprecipitation of multiple samples without the usual tedium of pipetting, centrifuging and separating beaded affinity resin in individual microcentrifuge tubes. Immunoprecipitation is accomplished using coated 96-well microplates rather than beaded agarose resin. The plate format allows for faster processing of multiple samples.

Features of the Streptavidin Coated Plate IP Kit:

• Ready-to-use, high quality coated plates provide high capacity and consistency
• Plate format best suited for simultaneously processing multiple samples and their control conditions
• Faster, easier and more thorough washing than with traditional tube/resin IP methods
• Uses familiar and convenient ELISA tools (multichannel pipettors and plate washing); no tedious separation of supernatant from pelleted resin beads, and no tubes to open and close and centrifuge
• Coated plates are 96-well strip plates, convenient for experiments requiring only a partial plate
• Easy-to-follow instructions, including detailed explanation of appropriate controls

Applications:
• Rapid, trouble-free immunoprecipitation of multiple samples and their controls
• Immunoprecipitation when plate-based tools and techniques are preferred

Streptavidin is a protein that binds specifically and very strongly to biotin; therefore, the Streptavidin Coated Plate IP Kit (Part No. 45360) is appropriate for immunoprecipitation when using a biotin-labeled (biotinylated) antibody. In fact, this kit can be used to affinity purify a binding partner to any antibody species or subclass or any other protein or molecule that is biotinylated. Because the streptavidin-biotin affinity interaction is so strong, the elution step generally will dissociate only the antigen (binding partner), not the biotinylated antibody or "bait" protein.

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Pierce™ Protein A/G Coated Plate IP Kit

Pierce™ Peroxide Assay Reagent A (Thermo Scientific™)

Thermo Scientific Pierce Peroxide Assay Reagent A is a formulation consisting of 25mM ammonium ferrous sulfate. This formulation is one of the component of Quantitative Peroxide Assay Kit used for detecting and measuring hydrogen peroxide levels based on the oxidation of ferrous to ferric ion in the presence of xylenol orange, present in the biological and other liquid samples.

Applications of Pierce Quantitative Peroxide Assay Kits:
• General hydrogen peroxide (H2O2) measurement in protein samples
• Quantitation of peroxides in detergents
• Assessment of the effects of peroxides on cellular activity
• Determination of protein glycation; Measurement of peroxide accumulation in lipids

In these assay kits, hydroperoxides convert the Fe2+ to Fe3+ at acidic pH. With the aqueous-compatible formulation, peroxide first reacts with sorbitol, converting it to a peroxyl radical, which in turn initiates Fe2+ oxidation to Fe3+. In the lipid compatible formulation, the peroxide converts the Fe2+ to Fe3+ directly. In a sulfuric acid solution, the Fe3+ complexes with the xylenol orange (XO) dye to yield a purple product having an absorbance maximum at 560nm. Peroxide levels in test samples can be determined by calculation from the know extinction coefficient of the XO-Fe complex or by reference to a standard curve prepared with hydrogen peroxide solution.Most proteins do not interfere with these assays, although some metal chelators may require use of a blank (i.e., control) to mitigate these effects.


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Pierce™ Quantitative Peroxide Assay Kit (Aqueous)
Pierce™ Quantitative Peroxide Assay Kit (Lipid)
Pierce™ Peroxide Assay Reagent B
Pierce™ Peroxide Assay Reagent C

Micro BCA™ Reagent A (MA) (Thermo Scientific™)

Thermo Scientific Pierce Micro BCA Reagent A (MA) is a proprietary alkaline tartrate-carbonate buffer. This product is sufficient for 3200 microplate assays when mixed with Reagents MB and MC.

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Micro BCA™ Protein Assay Kit
Micro BCA™ Reagent B (MB)
Micro BCA™ Reagent C (MC)

Pierce™ Coomassie (Bradford) Protein Assay Kit (Thermo Scientific™)

The Thermo Scientific Pierce Coomassie Protein Assay Kit is a ready-to-use, stable formulation of the traditional Bradford assay reagent to measure (A595 nm) total protein concentration compared to a protein standard.

The Pierce Coomassie Protein Assay Kit is a ready-to-use formulation of the popular assay reagent originally described by Bradford in 1976. When mixed with a protein solution, the acidic coomassie-dye reagent changes color from brown to blue in proportion the amount of protein present in the sample. Protein determinations are made by comparison to the color response of protein assay standards, usually prepared as a series of known dilutions of bovine serum albumin (BSA) or bovine gamma globulin (BGG). The kit includes Coomassie Protein Assay Reagent and a package of Albumin Standard Ampules. The simple procedure is adaptable to nearly any volume scale, including test tubes, cuvettes and microplates.

Features of the Coomassie Protein Assay Kit:

Bradford reagent—stable, ready-to-use kit of the classical Bradford assay reagent
Colorimetric—measure with a standard spectrophotometer or plate reader (595 nm)
Easy to use—single reagent; no working reagent preparation required
Fast—almost immediate color development; add, mix and read results
Broad range—detects protein concentration in the range 1 to 1500 µg/mL
Flexible—microplate and cuvette protocols provided with the instructions and adaptable to several target working ranges

How the Coomassie (Bradford) Assay Detects Protein
Use of coomassie G-250 dye in a colorimetric reagent for the detection and quantitation of total protein was first described by Dr. Marion Bradford in 1976. In the acidic environment of the reagent, protein binds to the coomassie dye. This results in a spectral shift from the reddish/brown form of the dye (absorbance maximum at 465nm) to the blue form of the dye (absorbance maximum at 610 nm). The difference between the two forms of the dye is greatest at 595 nm, so that is the optimal wavelength to measure the blue color from the coomassie dye-protein complex. If desired, the blue color can be measured at any wavelength between 575 nm and 615 nm. At the two extremes (575 nm and 615 nm) there is a loss of about 10% in the measured amount of color (absorbance) compared to that obtained at 595 nm.

Development of color in coomassie dye-based (Bradford) protein assays has been associated with the presence of certain basic amino acids (primarily arginine, lysine and histidine) in the protein. Van der Waals forces and hydrophobic interactions also participate in the binding of the dye by protein. The number of Coomassie dye ligands bound to each protein molecule is approximately proportional to the number of positive charges found on the protein. Free amino acids, peptides and low molecular weight proteins do not produce color with coomassie dye reagents. In general, the mass of a peptide or protein must be at least 3000 daltons to be assayed with this reagent. The assay is performed at room temperature and no special equipment is required. Simply add the sample to the tube containing reagent and the resultant blue color is measured at 595 nm following a short room-temperature incubation. The coomassie dye containing protein assay is compatible with most salts, solvents, buffers, thiols, reducing substances and metal chelating agents encountered in protein samples.

For more information, see the article "Chemistry of Protein Assays" in the Protein Methods Library.

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Pierce™ Coomassie Plus (Bradford) Assay Kit
Pierce™ Detergent Compatible Bradford Assay Kit
Ampule Breakers

CBQCA Protein Quantitation Kit (Invitrogen™)

The CBQCA Protein Quantitation Kit is a very sensitive assay for quantitating proteins in solution, capable of detection as low as 10 ng of protein per mL. Similar in sensitivity to our NanoOrange protein quantitation reagent (N-6666), CBQCA is better suited for accurate quantitation of proteins in the presence of lipids, membrane fractions or detergents, and for lipoproteins and small peptides.

tRNA for LightShift™ Chemiluminescent RNA EMSA Kit (Thermo Scientific™)

tRNA, formulation: Transfer RNA at 10 mg/mL in 10mM HEPES.
Sufficient For: 100 binding reactions

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LightShift™ Chemiluminescent RNA EMSA Kit

Pierce™ Microplate BCA Protein Assay Kit - Reducing Agent Compatible (Thermo Scientific™)

This BCA Protein Assay Kit is the reducing agent-compatible version of our popular Thermo Scientific Pierce BCA Protein Assay. The kit enables you to measure protein concentration in samples that contain thiol-reductants dithiothreitol (DTT) and 2-mercaptoethanol (BME), and comes with 20 96-well microplates.

Features of the Microplate BCA Protein Assay Kit—Reducing Agent Compatible:

Compatible—assay samples that contain up to 5 mM DTT, 35 mM BME, or 10 mM TCEP
BCA technology—only a slight modification of the standard BCA Protein Assay protocol (15-minute incubation with Compatibility Reagent); no precipitation steps required
Small samples—requires only 25 µL (standard kit) or less than 10 µL (microplate kit) of sample
Colorimetric—measure with a standard spectrophotometer or plate reader (562nm)
Excellent uniformity—exhibits less protein-to-protein variation than dye-binding methods
High linearity—linear working range for BSA equals 125 to 2000 µg/mL

The BCA Protein Assay Kit—Reducing Agent Compatible (BCA-RAC) provides all of the advantages of the original BCA Assay, plus compatibility with disulfide reducing agents at concentrations routinely used in protein sample buffers. This special adaptation of the popular Pierce BCA Protein Assay method enables accurate protein concentration measurement for samples containing DTT, 2-ME or TCEP. This reducing agent compatible (RAC) BCA Kit extends the already broad reagent compatibility of the BCA Protein Assay protocol to include nearly all types of components commonly present in protein research samples.

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Pierce™ BCA Protein Assay Kit - Reducing Agent Compatible
96-Well Plates for Pierce™ BCA-RAC Assay
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Pierce™ Peroxide Assay Reagent B (Thermo Scientific™)

Thermo Scientific Pierce Peroxide Assay Reagent B is a formulation consisting of 125µM xylenol orange in water with sorbitol. This formulation is one of the component of Quantitative Peroxide Assay Kit used for detecting and measuring hydrogen peroxide levels based on the oxidation of ferrous to ferric ion in the presence of xylenol orange, present in the biological and other liquid samples.

Features of Peroxide Assay Reagent B:

Convenient—no proprietary reagents involved and remove the variability, difficulty and added expense of formulating the reagents yourself
Aqueous-compatible formulations— the formulation includes sorbitol, which provides enhanced sensitivity with non-lipid samples

Applications of Pierce Quantitative Peroxide Assay Kits:
• General hydrogen peroxide (H2O2) measurement in protein samples
• Quantitation of peroxides in detergents
• Assessment of the effects of peroxides on cellular activity
• Determination of protein glycation; Measurement of peroxide accumulation in lipids

In these assay kits, hydroperoxides convert the Fe2+ to Fe3+ at acidic pH. With the aqueous-compatible formulation, peroxide first reacts with sorbitol, converting it to a peroxyl radical, which in turn initiates Fe2+ oxidation to Fe3+. In the lipid compatible formulation, the peroxide converts the Fe2+ to Fe3+ directly. In a sulfuric acid solution, the Fe3+ complexes with the xylenol orange (XO) dye to yield a purple product having an absorbance maximum at 560nm. Peroxide levels in test samples can be determined by calculation from the know extinction coefficient of the XO-Fe complex or by reference to a standard curve prepared with hydrogen peroxide solution.Most proteins do not interfere with these assays, although some metal chelators may require use of a blank (i.e., control) to mitigate these effects.

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Pierce™ Quantitative Peroxide Assay Kit (Aqueous)
Pierce™ Quantitative Peroxide Assay Kit (Lipid)
Pierce™ Peroxide Assay Reagent A
Pierce™ Peroxide Assay Reagent C

Rapid ELISA Mouse mAb Isotyping Kit (Thermo Scientific™)

The Thermo Scientific Pierce Rapid ELISA Mouse mAb Isotyping Kit provides antigen-independent determination of mouse monoclonal antibody isotype using a microplate method that enables multiple samples to be tested in about one hour.

Features of the Rapid ELISA Mouse mAb Isotyping Kit:

Fast—determine antibody isotype in approx. 1 hour; considerably faster than traditional ELISA kits
Convenient—eight-well strip format allows partial use of the plate; use one strip (column) for each sample (12 samples per plate)
Specific—characterize antibodies for six different subclasses and two different light-chain types
Sensitive—accurate characterization with samples containing at least 3 ng/mL of test antibody
Flexible—kit is compatible with hybridoma cell culture supernatant, ascites fluid or purified antibodies
Cost effective—cost per assay is less than with single-use assay strips or cassettes
No special equipment needed—assess results visually or measure quantitatively using an ordinary ELISA plate reader (450nm)
Complete and easy to use—includes precoated plates, detecting antibody, buffers, and TMB substrate and stop solutions

This fast assay uses ELISA strip-plates that are pre-coated in different wells with anti-mouse heavy-chain capture antibodies (anti-IgG1, IgG2a, IgG2b, IgG3, IgA and IgM) or anti-mouse light-chain capture antibody (kappa or lambda). This approach eliminates the need to purify and immobilize an antigen to determine immunoglobulin isotype (antibody subclass and light chain identity). A mouse monoclonal antibody sample applied to the wells can be isotyped within one hour. Results are evaluated qualitatively by visual inspection or quantitatively by measuring the absorbance at 450nm.

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Pierce™ Rapid Antibody Isotyping Kit - Mouse
Pierce™ Rapid Antibody Isotyping Kit plus Kappa and Lambda - Mouse

Qubit™ Protein Assay Kit (Invitrogen™)

The Qubit Protein Assay Kit is designed specifically for use with the Qubit Fluorometer. Using between 1 and 20 µl of your sample, this assay can quantitate samples ranging from 12.5 µg⁄ml to 5 mg⁄ml and exhibits low protein to protein variation. The assay is highly selective for proteins and is designed to be accurate in the presence of reducing reagents, but not in the presence of a large amount of detergent. Common contaminants, such as reducing reagents (DTT, β-mercaptoethanol), salts, free nucleotides, amino acids, solvents, or DNA, but not detergents, are well tolerated in the assay. Slight protocol modifications are required for other contaminants. The kit provides concentrated assay reagent, dilution buffer, and pre-diluted BSA standards. Simply dilute the reagent using the buffer provided, add your sample (any volume between 1 µL and 20 µL is acceptable), and read the concentration.

Which product to choose for fluorometric protein quantitation?
• For 1–20 samples: use this Qubit Protein Assay Kit with the Qubit Fluorometer
• For 20–2000 samples: use the Quant-iT Protein Assay Kit with microplate reader

Notes:
1. All Qubit assay kits can be used with the Qubit 1.0, Qubit 2.0, Qubit 3, and Qubit 4 fluorometers.
2. 500 µL thin-walled PCR tubes are required but not included.

Pierce™ Detergent Compatible Bradford Assay Kit (Thermo Scientific™)

The Thermo Scientific™ Pierce™ Detergent Compatible Bradford Assay Kit is a quick and ready-to-use modification of the well-known Bradford coomassie dye-binding, colorimetric method for total protein quantitation. Proprietary additives to the Bradford Reagent make it compatible with up to 1% or higher of detergents and lysis reagents that are commonly used in life science research, including Triton® X-100 and NP-40.

• Convenient— detergent-free standard curve
• Flexible— compatible with samples both with and without detergent
• Minimal sample—requires only 10 µL for microplate procedure
• Colorimetric—measure with a standard spectrophotometer or plate reader (595 nm)
• Easy to use— single reagent, no working reagent preparation required
• Fast—10 minute incubation at room temperature
• Broad range—detects protein concentration in the ranges of 2 to 1500 µg/mL

Similar to the Bradford method, coomassie dye binds protein in an acidic medium causing an immediate shift in absorption maximum from 465 nm to 595 nm with a concomitant color change from green to blue. In addition, the assay is complete in just 10 minutes.

The protein assay can be performed in either test tube or microplate format. The standard working range is 100-1500 µg/mL with up to 1% detergent (or higher in some cases). Protein concentrations are estimated by reference to absorbances obtained for a series of standard protein dilutions, typically bovine serum albumin (BSA), which are assayed alongside the unknown samples. Because the color response with coomassie dye is non-linear with increasing protein concentration, a standard curve must be completed with each assay. Standards can be used directly without preparing them in the same detergent found in the test samples.

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Pierce™ Phosphoprotein Phosphate Estimation Assay Kit (Thermo Scientific™)

The Thermo Scientific Phosphoprotein Phosphate Estimation Kit enables classification and identification of proteins as phosphorylated (serine and threonine), as well as semi-quantitative assessment of the phosphorylation level.

Features of the Phosphoprotein Phosphate Estimation Kit:

Specific—measures phosphoserine (p-Ser) and phosphothreonine (p-Thr) only; does not measure phosphotyrosine (p-Tyr)
Convenient—test tube and 96-well microplate protocols included and require less than 90 minutes to perform
Semi-quantitative—calculate moles of phosphate (P) per mole of protein using the included phosvitin standard
Customizable—format is adaptable to development of specific assays for pure phosphoproteins when previously characterized standards are available

The Phosphoprotein Phosphate Estimation Assay Kit is designed to aid in characterization of the status and extent of phosphorylation of purified protein samples. The assay is based on the alkaline hydrolysis of phosphate from seryl and threonyl residues in phosphoproteins and quantification of the released phosphate with malachite green and ammonium molybdate. The assay is easily performed in 96-well microplates or test tubes and is completed in about one hour.

Applications:
• Identify proteins as containing phosphoserine or phosphothreonine phosphorylations
• Estimate the amount of pS and pT phosphorylation
• Develop specific quantitative assays for well-characterized phosphoproteins of interest

The assay can be used to identify whether a purified protein contains either phospho-serine (p-Ser) or phospho-threonine (p-Thr) as well as to estimate the level of this type of phosphorylation. For quantitation, the test protein sample is compared with specific concentrations of phosvitin, a phosphoprotein of known phosphorylation level. The alkaline hydrolysis step does not release phosphate from phospho-tyrosine (p-Tyr) residues in peptide linkage. Therefore, a negative result for an unknown purified protein preparation indicates that the protein is either (1) not a phosphoprotein or (2) is phosphorylated exclusively at tyrosine residues. In the latter case, Western blot analysis using an anti-phosphotyrosine antibody will be necessary to distinguish between these two possibilities.

Pierce™ Protein A/G Coated Plate IP Kit (Thermo Scientific™)

The Thermo Scientific Pierce Protein A/G Coated Plate IP Kit uses coated Protein A/G microplates to perform immunoprecipitation assays in 96-well plates without resins, beads, centrifugation or magnets.

Pierce Coated Plate IP Kits enable rapid immunoprecipitation of multiple samples without the usual tedium of pipetting, centrifuging and separating beaded affinity resin in individual microcentrifuge tubes. Immunoprecipitation is accomplished using coated 96-well microplates rather than beaded agarose resin. The plate format allows for faster processing of multiple samples.

Features of the Protein A/G Coated Plate IP Kit:

• Ready-to-use, high quality coated plates provide high capacity and consistency
• Plate format best suited for simultaneously processing multiple samples and their control conditions
• Faster, easier and more thorough washing than with traditional tube/resin IP methods
• Uses familiar and convenient ELISA tools (multichannel pipettors and plate washing); no tedious separation of supernatant from pelleted resin beads, and no tubes to open and close and centrifuge
• Coated plates are 96-well strip plates, convenient for experiments requiring only a partial plate
• Easy-to-follow instructions, including detailed explanation of appropriate controls

Applications:
• Rapid, trouble-free immunoprecipitation of multiple samples and their controls
• Immunoprecipitation when plate-based tools and techniques are preferred

Protein A and Protein G are different proteins that bind to immunoglobulins (primarily only IgG). Typically, Protein A is preferred for use with Rabbit polyclonal antibodies, while Protein G is preferred for use with mouse antibodies (especially monoclonals of the IgG1 subclass). Protein A/G is a recombinant of Protein A and Protein G that has the additive binding properties of both proteins. Compare Protein A, Protein G and other antibody-binding proteins.

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Pierce™ Streptavidin Coated Plate IP Kit

Micro BCA™ Reagent B (MB) (Thermo Scientific™)

Thermo Scientific Pierce Micro BCA Reagent B (MB) is a proprietary bicinchonic acid solution. This product is sufficient for 3200 microplate assays when mixed with Reagents MA and MC.

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Micro BCA™ Protein Assay Kit
Micro BCA™ Reagent A (MA)
Micro BCA™ Reagent C (MC)