Screening Reagents

In order to observe activity inside certain cells, a screening reagent is used. These agents produce insoluble precipitates of various colors in screening for the presence of certain enzymatic activity. Screening reagents of high quality produce the best results, and using GoldBio branded reagents allows for the clearest results.
Showing 1-20 of 22 items.

2,3,5-Triphenyltetrazolium chloride (TTC; Tetrazolium chloride)

Catalog ID Size Pricing
T-112-100 100 g $ 165.00
T-112-250 250 g $ 375.00
T-112-500 500 g $ 695.00

Description

Tetrazolium red is used to visualize dehydrogenase enzyme activity. Initially, the tetrazolium solution is colorless but changes to red when it comes into contact with hydrogen. Tetrazolium red is used in a biochemical viability test for seeds. The test relies on dehydrogenase enzymes to release hydrogen ions, which subsequently reduce the colorless tetrazolium salt solution to a red compound called formazan. Living cells turn red while dead cells remain colorless.

Product Specifications

Catalog ID T-112
CAS # 298-96-4
MW 334.81 g/mol
Grade MOLECULAR BIOLOGY GRADE
Storage/Handling Store at 4°C. Protect from light.
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T-112-100 100 g $ 165.00
T-112-250 250 g $ 375.00
T-112-500 500 g $ 695.00

4-Methylumbelliferyl Caprylate

Catalog ID Size Pricing
M-540-1 1 g $ 125.00
M-540-5 5 g $ 539.00
M-540-10 10 g $ 1,009.00

Description

4-Methylumbelliferyl caprylate is a fluorogenic substrate for esterase with C8 activity, yielding a blue fluorescent solution upon cleavage and is used for the identification of Salmonella spp. based on the detection of caprylate esterase.

Product Specifications

Catalog ID M-540
CAS # 20671-66-3
MW 302.37 g/mol
Grade MOLECULAR BIOLOGY GRADE
Storage/Handling Store at -20°C. Protect from light.
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M-540-1 1 g $ 125.00
M-540-5 5 g $ 539.00
M-540-10 10 g $ 1,009.00

4-Nitrophenyl-α-D- glucopyranoside

Catalog ID Size Pricing
N-310-10 10 g $ 185.00
N-310-25 25 g $ 435.00
N-310-50 50 g $ 825.00

Description

4-Nitrophenyl-α-D- glucopyranoside is a chromogenic substrate for alpha-D-glucosidase, yielding a yellow solution upon cleavage. 4-Nitrophenyl-α-D- glucopyranoside is also used for the detection of glucansucrases and for yeast alpha-D-glucosidase and for crystal structure studies of the complexes of concanavalin A.

Product Specifications

Catalog ID N-310
CAS # 3767-28-0
MW 301.26 g/mol
Grade MOLECULAR BIOLOGY GRADE
Storage/Handling Store at -20°C. Protect from light.
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N-310-10 10 g $ 185.00
N-310-25 25 g $ 435.00
N-310-50 50 g $ 825.00

4-Nitrophenyl-α-D-glucopyranoside, beta-Anomer <0.1%

Catalog ID Size Pricing
N-311-5 5 g $ 149.00
N-311-10 10 g $ 269.00
N-311-25 25 g $ 605.00
N-311-50 50 g $ 1,095.00

Description

No description available

Product Specifications

Catalog ID N-311
CAS # 3767-28-0
MW 301.25 g/mol
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N-311-5 5 g $ 149.00
N-311-10 10 g $ 269.00
N-311-25 25 g $ 605.00
N-311-50 50 g $ 1,095.00

4-Nitrophenyl-β-D- galactosidase (p-Nitrophenyl-β-D-galactoside; PNP-β-D-Gal)

Catalog ID Size Pricing
N-290-10 10 g $ 129.00
N-290-25 25 g $ 295.00
N-290-50 50 g $ 545.00

Description

No description available

Product Specifications

Catalog ID N-290
CAS # 3150-24-1
MW 301.26 g/mol
Grade MOLECULAR BIOLOGY GRADE
Storage/Handling Store at -20°C. Protect from light.
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N-290-10 10 g $ 129.00
N-290-25 25 g $ 295.00
N-290-50 50 g $ 545.00

5-Bromo-4-chloro-3-indoxyl butyrate

Catalog ID Size Pricing
B-300-1 1 g $ 259.00

Description

Can be used as a substrate for carboxyl esterase, yielding a blue precipitate upon cleavage.

Product Specifications

Catalog ID B-300
CAS # 129541-43-1
MW 316.59 g/mol
Grade MOLECULAR BIOLOGY GRADE
Storage/Handling Store desiccated at -20°C. Protect from light.
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B-300-1 1 g $ 259.00

5-Bromo-4-chloro-3-indoxyl caprylate

Catalog ID Size Pricing
B-320-500 500 mg $ 85.00
B-320-2.5 2.5 g $ 229.00
B-320-5 5 g $ 365.00
B-320-10 10 g $ 579.00

Description

5-Bromo-4-chloro-3-indoxyl octanoate; X-caprylate

Product Specifications

Catalog ID B-320
CAS # 129541-42-0
MW 372.70 g/mol
Grade MOLECULAR BIOLOGY GRADE
Storage/Handling Store under inert gas at -20°C.
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B-320-500 500 mg $ 85.00
B-320-2.5 2.5 g $ 229.00
B-320-5 5 g $ 365.00
B-320-10 10 g $ 579.00

Bluo-Gal

Catalog ID Size Pricing
B-673-250 250 mg $ 59.00
B-673-500 500 mg $ 105.00
B-673-1 1 g $ 145.00
B-673-2.5 2.5 g $ 255.00
B-673-10 10 g $ 679.00

Description

Bluo-Gal is used as an alternative to X-Gal, and produces a darker blue color. Bluo-Gal is hydrolyzed by β-galactosidase to produce a blue precipitate. This precipitate is insoluble in alcohol and xylenes, thus making it suitable for immunoblotting and immunocytochemical assays. Bacterial colonies containing active β-galactosidase produce blue colonies when grown on plates containing Bluo-Gal.

Product Specifications

Catalog ID B-673
CAS # 97753-82-7
MW 374.18 g/mol
Grade MOLECULAR BIOLOGY GRADE
Storage/Handling Store at -20°C. Protect from light.
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B-673-250 250 mg $ 59.00
B-673-500 500 mg $ 105.00
B-673-1 1 g $ 145.00
B-673-2.5 2.5 g $ 255.00
B-673-10 10 g $ 679.00

DTNB (Ellman's Reagent)

Catalog ID Size Pricing
D-250-5 5 g $ 79.00
D-250-25 25 g $ 189.00
D-250-50 50 g $ 339.00
D-250-100 100 g $ 395.00

Description

Yellow crystalline powder that is used for the colorimetric determination of thiol groups in biological samples. DTNB is fairly soluble in water.

Product Specifications

Catalog ID D-250
CAS # 69-78-3
MW 396.36 g/mol
Grade MOLECULAR BIOLOGY GRADE
Storage/Handling Store at 4°C. Protect from light and heat.
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D-250-5 5 g $ 79.00
D-250-25 25 g $ 189.00
D-250-50 50 g $ 339.00
D-250-100 100 g $ 395.00

IPTG

Catalog ID Size Pricing
I2481C 1 g $ 25.00
I2481C5 5 g $ 35.00
I2481C25 25 g $ 145.00
I2481C50 50 g $ 225.00
I2481C100 100 g $ 415.00
I2481C200 200 g $ 795.00
I2481C300 300 g $ 1,059.00
I2481C400 400 g $ 1,375.00
I2481C500 500 g $ 1,655.00

Description

IPTG is an analog of galactose that is non-metabolizable and inactivates the lac repressor to induce synthesis of β-galactosidase in E. coli. The expression of cloned genes under the control of the lac operon is induced by IPTG. It is also a substrate for thigalactoside transacetylase and has been reported to induce penicillinase in bacteria.

Product Specifications

Catalog ID I2481
Name(s) IPTG
Isopropyl-beta-D-thiogalactoside
CAS # 367-93-1
Formula C9H18O5S
MW 238.30 g/mol
Grade MOLECULAR BIOLOGY GRADE
Storage/Handling Store desiccated at -20°C. Protect from light.
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I2481C 1 g $ 25.00
I2481C5 5 g $ 35.00
I2481C25 25 g $ 145.00
I2481C50 50 g $ 225.00
I2481C100 100 g $ 415.00
I2481C200 200 g $ 795.00
I2481C300 300 g $ 1,059.00
I2481C400 400 g $ 1,375.00
I2481C500 500 g $ 1,655.00

IPTG EZ Pak™ for 1 M Solution

Catalog ID Size Pricing
I2481-EZ10 10 mL $ 75.00
I2481-EZ50 50 mL $ 115.00
I2481-EZ100 100 mL $ 185.00

Description

The IPTG EZ Pak™ is the fastest and easiest way to make a set amount of sterile IPTG solution. The kit includes preweighed IPTG powder, a sterile filter, and a sterile container for the filtered solution. No need to calculate, simply add the stated amount of deionized H2O, filter, and pour into the labeled bottle for easy usage. The EZ Pak™ includes high quality GoldBio IPTG and the sterile solution is ready for tissue culture, bacterial media, or any other appropriate use.

Product Specifications

Catalog ID I2481-EZ
CAS # 367-93-1
MW 238.30 g/mol
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I2481-EZ10 10 mL $ 75.00
I2481-EZ50 50 mL $ 115.00
I2481-EZ100 100 mL $ 185.00

Lapis-3-Acetate

Catalog ID Size Pricing
B-650-2.5 2.5 g $ 169.00
B-650-5 5 g $ 295.00
B-650-10 10 g $ 505.00
B-650-25 25 g $ 1,099.00

Description

No description available

Product Specifications

Catalog ID B-650
CAS # 17357-14-1
MW 254.09 g/mol
Grade MOLECULAR BIOLOGY GRADE
Storage/Handling Store at -20°C. Protect from light.
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B-650-2.5 2.5 g $ 169.00
B-650-5 5 g $ 295.00
B-650-10 10 g $ 505.00
B-650-25 25 g $ 1,099.00

MUG

Catalog ID Size Pricing
MUG200 200 mg $ 25.00
MUG1 1 g $ 75.00
MUG5 5 g $ 285.00
MUG10 10 g $ 449.00
MUG25 25 g $ 899.00

Description

4-Methylumbelliferyl beta-D-glucuronide (MUG) is a fluorogenic substrate for beta-glucuronidase (GUS). Upon cleavage, MUG yields blue fluorescence seen under UV light.

This substrate is commonly used for the detection of Escherichia coli through its ability to detect activity of beta-glucuronidase, which is encoded by uidA. GUS activity is tested in minimal medium o-nitrophenyl-beta-D-galactopyranoside (MMO)-MUG.

It is ideal for plant molecular study as a way to examine gene expression under various promoters. And while it works well for measuring activity in plant lysate and leaf disks, it can also work in whole plant assays.

Product Specifications

Catalog ID MUG
CAS # 6160-80-1 or 881005-91-0
MW 388.32 g/mol
Grade MOLECULAR BIOLOGY GRADE
Storage/Handling Store desiccated at -20°C.
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MUG200 200 mg $ 25.00
MUG1 1 g $ 75.00
MUG5 5 g $ 285.00
MUG10 10 g $ 449.00
MUG25 25 g $ 899.00

N-Methylindoxyl-beta-D- galactopyranoside

Catalog ID Size Pricing
M-480-100 100 mg $ 135.00
M-480-500 500 mg $ 529.00
M-480-1 1 g $ 745.00
M-480-5 5 g $ 2,299.00

Description

Chromogenic substrate for beta-D-galactosidase, yielding a green precipitate upon cleavage

Product Specifications

Catalog ID M-480
CAS # 207598-26-3
MW 309.32 g/mol
Storage/Handling Store at -20°C. Protect from light.
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M-480-100 100 mg $ 135.00
M-480-500 500 mg $ 529.00
M-480-1 1 g $ 745.00
M-480-5 5 g $ 2,299.00

Nitrotetrazolium blue chloride (NBT)

Catalog ID Size Pricing
NBT1 1 g $ 65.00
NBT2.5 2.5 g $ 119.00
NBT5 5 g $ 195.00
NBT10 10 g $ 309.00

Description

Nitrotetrazolium Blue (NBT) is used in combination with 5-bromo-4-chloro-3-indoxyl phosphate (BCIP) to detect alkaline phosphatase activity in blotting techniques and in situ hybridization chemistry. BCIP acts as the substrate for alkaline phosphatase, and the oxidizing reagent NBT enhances the purple-brown final color of the precipitates at the reaction sites.

NBT has also been used with X-Gal,or Salmon-Gal to speed up and enhance colony screening.

Product Specifications

Catalog ID NBT
CAS # 298-83-9
MW 817.65 g/mol
Grade MOLECULAR BIOLOGY GRADE
Storage/Handling Store at 4°C. Protect from light.
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NBT1 1 g $ 65.00
NBT2.5 2.5 g $ 119.00
NBT5 5 g $ 195.00
NBT10 10 g $ 309.00

Salmon Gal (6-Chloro-3-indoxyl-β-D-galactopyranoside)

Catalog ID Size Pricing
C-255-1 1 g $ 85.00
C-255-2.5 2.5 g $ 185.00
C-255-5 5 g $ 275.00
C-255-10 10 g $ 455.00

Description

Salmon Gal (6-Chloro-3-indolyl-β-D-galactopyranoside) is used with IPTG as an alternative chromogenic substrate capable of detecting LacZ gene encoded ß-galactosidase activity for colony screening in colometric assays.

Unlike colony blue/white screening through X-Gal, nonrecombination results in a salmon color after salmon gal is cleaved by ß-galactosidase through hydrolysis. This contrast may be useful in comparative or secondary screenings.

Incorporating nitroblue tetrazolium salt (NBT) into the salmon gal reactions provides faster results with a clear, purple precipitate than in unaccompanied uses of salmon gal.

Product Specifications

Catalog ID C-255
CAS # 138182-21-5
MW 329.73 g/mol
Grade MOLECULAR BIOLOGY GRADE
Storage/Handling Store desiccated at -20°C. Protect from light.
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C-255-1 1 g $ 85.00
C-255-2.5 2.5 g $ 185.00
C-255-5 5 g $ 275.00
C-255-10 10 g $ 455.00

TMB dihydrochloride

Catalog ID Size Pricing
TMBHCL2 2 g $ 69.00
TMBHCL10 10 g $ 309.00
TMBHCL25 25 g $ 589.00
TMBHCL50 50 g $ 899.00

Description

TMB is an excellent colorimetric substrate for detection of horseradish peroxidase labeled probes and is used with peroxidase and peroxidase-coupled systems, particularly in ELISA techniques. It produces a soluble end product, which is blue in color and can be read spectrophotometrically. TMB has also been used in the quantitative determination of hemoglobin and in cytochemical staining for peroxidase. TMB is a hepatitis B antigen.

Product Specifications

Catalog ID TMBHCL
CAS # 207738-08-7
MW 313.27 g/mol
Grade MOLECULAR BIOLOGY GRADE
Storage/Handling Store desiccated at -20°C. Protect from light.
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TMBHCL2 2 g $ 69.00
TMBHCL10 10 g $ 309.00
TMBHCL25 25 g $ 589.00
TMBHCL50 50 g $ 899.00

TMB, free base

Catalog ID Size Pricing
TMBF10 10 g $ 69.00
TMBF25 25 g $ 165.00
TMBF50 50 g $ 265.00
TMBF100 100 g $ 475.00
TMBF250 250 g $ 1,045.00

Description

TMB is an excellent colorimetric substrate for detection of horseradish peroxidase labeled probes and is used with peroxidase and peroxidase-coupled systems, particularly in ELISA techniques. It produces a soluble end product, which is blue in color and can be read spectrophotometrically. TMB has also been used in the quantitative determination of hemoglobin and in cytochemical staining for peroxidase. TMB is a hepatitis B antigen.

Product Specifications

Catalog ID TMBF
CAS # 54827-17-7
MW 240.35 g/mol
Grade MOLECULAR BIOLOGY GRADE
Storage/Handling Store desiccated at 4°C. Protect from light.
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TMBF10 10 g $ 69.00
TMBF25 25 g $ 165.00
TMBF50 50 g $ 265.00
TMBF100 100 g $ 475.00
TMBF250 250 g $ 1,045.00

X-Gal

Catalog ID Size Pricing
X4281C 1 g $ 55.00
X4281C10 10 g $ 275.00

Description

5-Bromo-4-chloro-3-indolyl β-D-galactopyranoside is most commonly known as X-Gal. X-gal is a histochemical substrate for β-galactosidase which cleaves X-Gal to yield an insoluble blue precipitate.

X-Gal is a mainstay in molecular biology cloning applications in which it is used to detect the activity of β-galactosidase. X-Gal is used to detect the insertion of foreign DNA into the lacZ region of a plasmid DNA. Insertion of DNA into the lacZ region results in the loss of β-galactosidase activity. Bacteria cells that retain active β-galactosidase will result in characteristic blue colonies. Successful disruption of the lacZα gene disrupts the α-complementation of the β-galactosidase gene and the precipitate does not form, resulting in white colonies.

Many other applications also use X-Gal as a substrate to detect β-galactosidase activity. These include β-galactosidase -antibody linked immunoassays and immunohistochemistry, coliphage detection based on β-galactosidase induction and the detection of micrometastasis formation during tumor progession.

Product Specifications

Catalog ID X4281
CAS # 7240-90-6
MW 408.63 g/mol
Grade MOLECULAR BIOLOGY GRADE
Storage/Handling Store at -20°C. Protect from light.
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X4281C 1 g $ 55.00
X4281C10 10 g $ 275.00

X-gluc (CHX salt)

Catalog ID Size Pricing
G1281C 100 mg $ 55.00
G1281C1 1 g $ 195.00
G1281C2 2 x 1 g $ 375.00
G1281C3 3 x 1 g $ 529.00
G1281C4 4 x 1 g $ 635.00
G1281C5 5 g $ 735.00

Description

X-Gluc is a chromogenic substrate for beta-glucuronidase (GUS) which is encoded by the gusA (uid A) gene, a widely used reporter gene. Glucuronidase cleaves X-Gluc to produce colorless glucuronic acid and an intense blue precipitate. X-Gluc is often used in GUS staining of plant cells and tissue and in infections caused by E. coli.

Product Specifications

Catalog ID G1281
CAS # 114162-64-0
MW 521.79 g/mol
Grade MOLECULAR BIOLOGY GRADE
Storage/Handling Store desiccated at -20°C. Protect from light.
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G1281C 100 mg $ 55.00
G1281C1 1 g $ 195.00
G1281C2 2 x 1 g $ 375.00
G1281C3 3 x 1 g $ 529.00
G1281C4 4 x 1 g $ 635.00
G1281C5 5 g $ 735.00

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