Classical Cross-Linkers – VectorLabs https://staging.vectorlabs.com From linker design and synthesis, bioconjugated design and manufacturing, biomolecule labeling and functionalization, and detection system and solutions, our team is here to help you move forward, with impact. Wed, 22 Oct 2025 17:17:32 +0000 en-US hourly 1 https://wordpress.org/?v=6.8.3 https://staging.vectorlabs.com/wp-content/uploads/2024/11/V-favicon-02-100x100.png Classical Cross-Linkers – VectorLabs https://staging.vectorlabs.com 32 32 MPS-Acid https://staging.vectorlabs.com/products/mps-acid/ Sat, 24 Feb 2024 02:10:03 +0000 https://staging.vectorlabs.com/?post_type=product&p=35984 "MPS-Acid, product number QBD-10323, is 3-maleimidopropanoic acid, a thiol-reactive crosslinker for linking sulfhydryl groups with free amines. Although it is not a dPEG® product, MPS-Acid is a building block for Vector Laboratories' complete line of Maleimide-dPEG®x products. As a crosslinker, the spacer is from the reactive site of the maleimide to the carbonyl carbon of the propanoic acid.

The maleimido group reacts with sulfhydryl groups to form thiol ether bonds. In the range of pH 6.5 – 7.5, the thiol-maleimide reaction is chemoselective. Above pH 7.5, the maleimide group can also react with free amine groups. Consequently, high pH buffers should be avoided when using this product.

This product can be functionalized with an active ester such as N-hydroxysuccinimide (NHS); 2,3,5,6-tetrafluorophenol (TFP); or 2,3,4,5,6-pentafluorophenol (PFP) in order to react with free amines. Alternatively, the acid moiety can be coupled directly to free amines using a water-soluble carbodiimide such as 1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC)."

Specifications

Unit Size 100 mg, 1000 mg
Molecular Weight 169.13; single compound
Chemical formula C₇H₇NO₄
CAS 7423-55-4
Purity > 98%
Spacers Spacer is 6 atoms and 6.0 Å
Shipping Ambient
Typical solubility properties (for additional information contact Customer Support) Acetonitrile, DMAC, DMSO or water.
Storage and handling -20°C; Always let come to room temperature before opening; be careful to limit exposure to moisture and restore under an inert atmosphere; stock solutions can be prepared with dry solvent and kept for several days (freeze when not in use). dPEG® pegylation compounds are generally hygroscopic and should be treated as such. This will be less noticeable with liquids, but the solids will become tacky and difficult to manipulate, if care is not taken to minimize air exposure.

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Description

MPS-Acid, product number QBD-10323, is 3-maleimidopropanoic acid, a thiol-reactive crosslinker for linking sulfhydryl groups with free amines. Although it is not a dPEG® product, MPS-Acid is a building block for Vector Laboratories’ complete line of Maleimide-dPEG®x products. As a crosslinker, the spacer is from the reactive site of the maleimide to the carbonyl carbon of the propanoic acid.

The maleimido group reacts with sulfhydryl groups to form thiol ether bonds. In the range of pH 6.5 – 7.5, the thiol-maleimide reaction is chemoselective. Above pH 7.5, the maleimide group can also react with free amine groups. Consequently, high pH buffers should be avoided when using this product.

This product can be functionalized with an active ester such as N-hydroxysuccinimide (NHS); 2,3,5,6-tetrafluorophenol (TFP); or 2,3,4,5,6-pentafluorophenol (PFP) in order to react with free amines. Alternatively, the acid moiety can be coupled directly to free amines using a water-soluble carbodiimide such as 1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC).

Specifications

Unit Size100 mg, 1000 mg
Molecular Weight169.13; single compound
Chemical formulaC₇H₇NO₄
CAS7423-55-4
Purity> 98%
SpacersSpacer is 6 atoms and 6.0 Å
ShippingAmbient
Typical solubility properties (for additional information contact Customer Support)Acetonitrile, DMAC, DMSO or water.
Storage and handling-20°C; Always let come to room temperature before opening; be careful to limit exposure to moisture and restore under an inert atmosphere; stock solutions can be prepared with dry solvent and kept for several days (freeze when not in use). dPEG® pegylation compounds are generally hygroscopic and should be treated as such. This will be less noticeable with liquids, but the solids will become tacky and difficult to manipulate, if care is not taken to minimize air exposure.



Documents

References

Greg T. Hermanson, Bioconjugate Techniques, 3rd Edition, Elsevier, Waltham, MA 02451, 2013, ISBN 978-0-12-382239-0; See Chapter 18, Discrete PEG Reagents, pp. 787-821, for a full overview of the dPEG® products.

The post MPS-Acid appeared first on VectorLabs.

]]> Bis-Maleimide amine,TFA salt https://staging.vectorlabs.com/products/bis-maleimide-aminetfa-salt/ Sat, 24 Feb 2024 02:07:27 +0000 https://staging.vectorlabs.com/?post_type=product&p=35523 Bis-Maleimide amine, TFA salt, product number QBD-10232, is a crosslinking product designed to bridge disulfide bonds. Built around a lysine core, maleimido-propanoate modifies both the α and ε amino groups of lysine. Diaminohexane converts the carboxylic acid of lysine to an amine (as a TFA salt). This is not a dPEG® product; however, it can react with the carboxylic acid termini of dPEG® products to form new products.

Description

Bis-Maleimide amine, TFA salt, product number QBD-10232, is a crosslinking product designed to bridge disulfide bonds. Built around a lysine core, maleimido-propanoate groups modify the α and ε amine of lysine. Diaminohexane converts the carboxylic acid of lysine to an amine (as a TFA salt). This is not a dPEG® product; however, it can react with the carboxylic acid termini of dPEG® products to form new products.

Bis-Maleimide amine, TFA salt, is designed to bridge disulfide bonds. The spacer length from maleimide reactive site through the α-amino group to the terminal amine-TFA salt is 17 atoms and 19.1 Å. The spacer length from the maleimide double bond through the ε-amino group to the terminal amine-TFA salt is 21 atoms and 19.6 Å.
Bis-Maleimide amine, TFA salt, is designed to bridge disulfide bonds. The spacer length from maleimide reactive site through the α-amino group to the terminal amine-TFA salt is 17 atoms and 19.1 Å. The spacer length from the maleimide double bond through the ε-amino group to the terminal amine-TFA salt is 21 atoms and 19.6 Å.

Specifications

Unit Size 100 mg, 1000 mg
Molecular Weight 660.64; single compound
Chemical formula C₂₈H₃₉F₃N₆O₉
CAS 1301738-40-8
Purity > 95%
Spacers Spacer is 17 and 21 atoms and 19.1 and 19.6 Å
Shipping Ambient
Typical solubility properties (for additional information contact Customer Support) DMAC, DMSO or water.
Storage and handling -20°C; Always let come to room temperature before opening; be careful to limit exposure to moisture and restore under an inert atmosphere; stock solutions can be prepared with dry solvent and kept for several days (freeze when not in use). dPEG® pegylation compounds are generally hygroscopic and should be treated as such. This will be less noticeable with liquids, but the solids will become tacky and difficult to manipulate, if care is not taken to minimize air exposure.

The post Bis-Maleimide amine,TFA salt appeared first on VectorLabs.

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Bis-Maleimide amine, TFA salt, product number QBD-10232, is a crosslinking product designed to bridge disulfide bonds. Built around a lysine core, maleimido-propanoate modifies both the α and ε amino groups of lysine. Diaminohexane converts the carboxylic acid of lysine to an amine (as a TFA salt). This is not a dPEG® product; however, it can react with the carboxylic acid termini of dPEG® products to form new products.

Description

Bis-Maleimide amine, TFA salt, product number QBD-10232, is a crosslinking product designed to bridge disulfide bonds. Built around a lysine core, maleimido-propanoate groups modify the α and ε amine of lysine. Diaminohexane converts the carboxylic acid of lysine to an amine (as a TFA salt). This is not a dPEG® product; however, it can react with the carboxylic acid termini of dPEG® products to form new products.

Bis-Maleimide amine, TFA salt, is designed to bridge disulfide bonds. The spacer length from maleimide reactive site through the α-amino group to the terminal amine-TFA salt is 17 atoms and 19.1 Å. The spacer length from the maleimide double bond through the ε-amino group to the terminal amine-TFA salt is 21 atoms and 19.6 Å.
Bis-Maleimide amine, TFA salt, is designed to bridge disulfide bonds. The spacer length from maleimide reactive site through the α-amino group to the terminal amine-TFA salt is 17 atoms and 19.1 Å. The spacer length from the maleimide double bond through the ε-amino group to the terminal amine-TFA salt is 21 atoms and 19.6 Å.

Specifications

Unit Size100 mg, 1000 mg
Molecular Weight660.64; single compound
Chemical formulaC₂₈H₃₉F₃N₆O₉
CAS1301738-40-8
Purity> 95%
SpacersSpacer is 17 and 21 atoms and 19.1 and 19.6 Å
ShippingAmbient
Typical solubility properties (for additional information contact Customer Support)DMAC, DMSO or water.
Storage and handling-20°C; Always let come to room temperature before opening; be careful to limit exposure to moisture and restore under an inert atmosphere; stock solutions can be prepared with dry solvent and kept for several days (freeze when not in use). dPEG® pegylation compounds are generally hygroscopic and should be treated as such. This will be less noticeable with liquids, but the solids will become tacky and difficult to manipulate, if care is not taken to minimize air exposure.

Documents

References

  1. Greg T. Hermanson, Bioconjugate Techniques, 3rd Edition, Elsevier, Waltham, MA 02451, 2013, ISBN 978-0-12-382239-0; See Chapter 18, Discrete PEG Reagents, pp. 787-821, for a full overview of the dPEG® products.
  2. Mono-PEGylated Dimeric Exendin-4 as High Receptor Binding and Long-Acting Conjugates for Type 2 Anti-Diabetes Therapeutics.Tae Hyung Kim, Hai Hua Jiang, Seulki Lee, Yu Seok Youn, Chan Woong Park,Youngro Byun, Xiaoyuan Chen, and Kang Choon Lee. Bioconjugate Chem. 2011, 22 (4), pp 625–632. March 14, 2011. DOI: 10.1021/bc100404x.
  3. Reorienting the Fab Domains of Trastuzumab Results in Potent HER2 Activators. Justin M. Scheer, Wendy Sandoval, J. Michael Elliott, Lily Shao, Elizabeth Luis, Sock-Cheng Lewin-Koh, Gabriele Schaefer, Richard Vandlen. PLOS ONE. 2012, 7 (12) e51817. December 20, 2012. DOI: 10.1371/journal.pone.0051817.

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]]> t-boc-N-EDA https://staging.vectorlabs.com/products/t-boc-n-eda/ Sat, 24 Feb 2024 02:07:24 +0000 https://staging.vectorlabs.com/?post_type=product&p=35509 t-boc-N-EDA, product number QBD-10226, CAS number 57260-73-8, is the boc-protected form of ethylenediamine. It is not a dPEG® product. However, it can be useful in bioconjugation reactions where an exceptionally short, monoprotected, homobifunctional crosslinker is needed. The free primary amine reacts with activated esters of carboxylic acids (for example, the N-hydroxysuccinimidyl ester, also known as NHS) to form amide bonds. Treatment of the resulting conjugate with acid (for example, TFA) removes the boc protecting group from the protected amine, leaving a primary amine that is free to react.

Specifications

Unit Size 1000 mg
Molecular Weight 160.21; single compound
Chemical formula C₁₅H₃₂N₂O₅
CAS 57260-73-8
Purity > 98%
Spacers dPEG® Spacer is 4 atoms and 3.8 Å
Shipping Ambient
Typical solubility properties (for additional information contact Customer Support) Methylene chloride, DMAC or DMSO.
Storage and handling -20°C; Always let come to room temperature before opening; be careful to limit exposure to moisture and restore under an inert atmosphere; stock solutions can be prepared with dry solvent and kept for several days (freeze when not in use). dPEG® pegylation compounds are generally hygroscopic and should be treated as such. This will be less noticeable with liquids, but the solids will become tacky and difficult to manipulate, if care is not taken to minimize air exposure.

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Description

t-boc-N-EDA, product number QBD-10226, CAS number 57260-73-8, is the boc-protected form of ethylenediamine. It is not a dPEG® product. However, it can be useful in bioconjugation reactions where an exceptionally short, monoprotected, homobifunctional crosslinker is needed. The free primary amine reacts with activated esters of carboxylic acids (for example, the N-hydroxysuccinimidyl ester, also known as NHS) to form amide bonds. Treatment of the resulting conjugate with acid (for example, TFA) removes the boc protecting group from the protected amine, leaving a primary amine that is free to react.

Specifications

Unit Size1000 mg
Molecular Weight160.21; single compound
Chemical formulaC₁₅H₃₂N₂O₅
CAS57260-73-8
Purity> 98%
SpacersdPEG® Spacer is 4 atoms and 3.8 Å
ShippingAmbient
Typical solubility properties (for additional information contact Customer Support)Methylene chloride, DMAC or DMSO.
Storage and handling-20°C; Always let come to room temperature before opening; be careful to limit exposure to moisture and restore under an inert atmosphere; stock solutions can be prepared with dry solvent and kept for several days (freeze when not in use). dPEG® pegylation compounds are generally hygroscopic and should be treated as such. This will be less noticeable with liquids, but the solids will become tacky and difficult to manipulate, if care is not taken to minimize air exposure.

Documents

References

  1. Greg T. Hermanson, Bioconjugate Techniques, 3rd Edition, Elsevier, Waltham, MA 02451, 2013, ISBN 978-0-12-382239-0; See Chapter 18, Discrete PEG Reagents, pp. 787-821, for a full overview of the dPEG® products.
  2. DEVD-NucView 488: a novel class of enzyme substrates for real-time detection of caspase-3 activity in live cells. Hui Cen, Fei Mao, Ida Aronchik, Rholinelle Joy Fuentes, and Gary L. Firestone. The FASEB Journal. 2008, (22), pp 2243-2252. July 2010. DOI: 10.1096/fj.07-099234.

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]]> MPS (NHS-3-maleimidopropionate) https://staging.vectorlabs.com/products/mps-nhs-3-maleimidopropionate/ Sat, 24 Feb 2024 02:07:15 +0000 https://staging.vectorlabs.com/?post_type=product&p=35449 "MPS (NHS-3-maleimidopropionate), product number QBD-10217, is the N-hydroxysuccinimidyl (NHS) ester of 3-(maleimido)propanoic acid and is used to crosslink sulfhydryls with amines. This product does not contain a dPEG® spacer between the reactive groups. The distance is six atoms (6.0 Å) from the reactive site of the maleimide to the carbonyl carbon of the propanoic acid.

The maleimido group reacts with sulfhydryl groups to form thiol ether bonds. In the range of pH 6.5 – 7.5, the thiol-maleimide reaction is chemoselective. Above pH 7.5, the maleimide group can also react with free amine groups. Consequently, high pH buffers should be avoided when using this product.

NHS esters are widely popular for reactions of carboxylic acids with primary or secondary amines to form stable amide bonds. Although the NHS ester hydrolyzes rather easily in water or aqueous buffer, this product can be dissolved in a water-miscible solvent such as N,N’-dimethylacetamide (DMAC) that has been dried over 3 Å molecular sieves. The solution of MPS is then added to the water or aqueous buffer to start the reaction."

Specifications

Unit Size 250 mg, 1000 mg
Molecular Weight 266.21; single compound
Chemical formula C₁₁H₁₀N₂O₆
CAS 55750-62-4
Purity > 98%
Spacers Spacer is 6 atoms and 6.0 Å
Shipping Ambient
Typical solubility properties (for additional information contact Customer Support) DMAC or DMSO.
Storage and handling -20°C; Always let come to room temperature before opening; be careful to limit exposure to moisture and restore under an inert atmosphere; stock solutions can be prepared with dry solvent and kept for several days (freeze when not in use). dPEG® pegylation compounds are generally hygroscopic and should be treated as such. This will be less noticeable with liquids, but the solids will become tacky and difficult to manipulate, if care is not taken to minimize air exposure.

The post MPS (NHS-3-maleimidopropionate) appeared first on VectorLabs.

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Description

MPS (NHS-3-maleimidopropionate), product number QBD-10217, is the N-hydroxysuccinimidyl (NHS) ester of 3-(maleimido)propanoic acid and is used to crosslink sulfhydryls with amines. This product does not contain a dPEG® spacer between the reactive groups. The distance is six atoms (6.0 Å) from the reactive site of the maleimide to the carbonyl carbon of the propanoic acid.

The maleimido group reacts with sulfhydryl groups to form thiol ether bonds. In the range of pH 6.5 – 7.5, the thiol-maleimide reaction is chemoselective. Above pH 7.5, the maleimide group can also react with free amine groups. Consequently, high pH buffers should be avoided when using this product.

NHS esters are widely popular for reactions of carboxylic acids with primary or secondary amines to form stable amide bonds. Although the NHS ester hydrolyzes rather easily in water or aqueous buffer, this product can be dissolved in a water-miscible solvent such as N,N’-dimethylacetamide (DMAC) that has been dried over 3 Å molecular sieves. The solution of MPS is then added to the water or aqueous buffer to start the reaction.

Specifications

Unit Size250 mg, 1000 mg
Molecular Weight266.21; single compound
Chemical formulaC₁₁H₁₀N₂O₆
CAS55750-62-4
Purity> 98%
SpacersSpacer is 6 atoms and 6.0 Å
ShippingAmbient
Typical solubility properties (for additional information contact Customer Support)DMAC or DMSO.
Storage and handling-20°C; Always let come to room temperature before opening; be careful to limit exposure to moisture and restore under an inert atmosphere; stock solutions can be prepared with dry solvent and kept for several days (freeze when not in use). dPEG® pegylation compounds are generally hygroscopic and should be treated as such. This will be less noticeable with liquids, but the solids will become tacky and difficult to manipulate, if care is not taken to minimize air exposure.

Documents

References

  1. Greg T. Hermanson, Bioconjugate Techniques, 3rd Edition, Elsevier, Waltham, MA 02451, 2013, ISBN 978-0-12-382239-0; See Chapter 18, Discrete PEG Reagents, pp. 787-821, for a full overview of the dPEG® products.
  2. Reagents for Astatination of Biomolecules. 2. Conjugation of Anionic Boron Cage Pendant Groups to a Protein Provides a Method for Direct Labeling that is Stable to in Vivo Deastatination. D. Scott Wilbur, Ming-Kuan Chyan, Donald K. Hamlin, Robert L. Vessella, Timothy J. Wedge, and M. Frederick Hawthorne. Bioconjugate Chem. 2007, 18 (4) pp 1226–1240. June 21, 2007. DOI: 10.1021/bc060345s.
  3. Biodistribution of 211At labeled HER-2 binding affibody molecules in mice. Ann-Charlotts teffen, Ylva Almqvist, Ming-Kuan Chyan, Hans Lundqvist, Vladimir Tolmachev, D. Scott Wilbur and Jorgen Carlsson. Oncology Reports. 2007, 17 (5) pp 1141-1147. May 1, 2007. DOI: www.spandidos-publications.com/or/17/5/1141.

The post MPS (NHS-3-maleimidopropionate) appeared first on VectorLabs.

]]> MPS-EDA.TFA https://staging.vectorlabs.com/products/mps-eda-tfa/ Sat, 24 Feb 2024 02:05:10 +0000 https://staging.vectorlabs.com/?post_type=product&p=35201 MPS-EDA•TFA, product number QBD-10177, is the trifluoroacetic acid salt of N-(2-aminoethyl)-3-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)propanamide. This product crosslinks a sulfhydryl group and a carboxylic acid. The spacer length from the maleimide reactive site to the terminal nitrogen is ten (10) atoms long (10.7 Å). The product is a highly water-soluble white solid. It is extremely stable under recommended storage conditions. Although this product does not contain a dPEG® linker or spacer, it can be conjugated to the carboxylic acid termini of various dPEG® products to form maleimide-functionalized constructs.

Specifications

Unit Size 100 mg, 1000 mg
Molecular Weight 325.24; single compound
Chemical formula C₁₁H₁₄F₃N₃O₅
CAS 11550-02-00
Purity > 98%
Spacers Spacer is 10 atoms and 10.7 Å
Shipping Ambient
Typical solubility properties (for additional information contact Customer Support) DMAC, DMSO or water.
Storage and handling -20°C; Always let come to room temperature before opening; be careful to limit exposure to moisture and restore under an inert atmosphere; stock solutions can be prepared with dry solvent and kept for several days (freeze when not in use). dPEG® pegylation compounds are generally hygroscopic and should be treated as such. This will be less noticeable with liquids, but the solids will become tacky and difficult to manipulate, if care is not taken to minimize air exposure.

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Description

MPS-EDA•TFA, product number QBD-10177, is the trifluoroacetic acid salt of N-(2-aminoethyl)-3-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)propanamide. This product crosslinks a sulfhydryl group and a carboxylic acid. The spacer length from the maleimide reactive site to the terminal nitrogen is ten (10) atoms long (10.7 Å). The product is a highly water-soluble white solid. It is extremely stable under recommended storage conditions. Although this product does not contain a dPEG® linker or spacer, it can be conjugated to the carboxylic acid termini of various dPEG® products to form maleimide-functionalized constructs.

Specifications

Unit Size100 mg, 1000 mg
Molecular Weight325.24; single compound
Chemical formulaC₁₁H₁₄F₃N₃O₅
CAS11550-02-00
Purity> 98%
SpacersSpacer is 10 atoms and 10.7 Å
ShippingAmbient
Typical solubility properties (for additional information contact Customer Support)DMAC, DMSO or water.
Storage and handling-20°C; Always let come to room temperature before opening; be careful to limit exposure to moisture and restore under an inert atmosphere; stock solutions can be prepared with dry solvent and kept for several days (freeze when not in use). dPEG® pegylation compounds are generally hygroscopic and should be treated as such. This will be less noticeable with liquids, but the solids will become tacky and difficult to manipulate, if care is not taken to minimize air exposure.

Documents

References

  1. Greg T. Hermanson, Bioconjugate Techniques, 3rd Edition, Elsevier, Waltham, MA 02451, 2013, ISBN 978-0-12-382239-0; See Chapter 18, Discrete PEG Reagents, pp. 787-821, for a full overview of the dPEG® products.

The post MPS-EDA.TFA appeared first on VectorLabs.

]]> Tris (2-carboxyethyl) phosphine hydrochloride (TCEP) https://staging.vectorlabs.com/products/tris-2-carboxyethyl-phosphine-hydrochloride-tcep/ Sat, 24 Feb 2024 02:04:31 +0000 https://staging.vectorlabs.com/?post_type=product&p=32740 Description

Tris(2-carboxyethyl)phosphine hydrochloride (commonly known as TCEP or TCEP-HCl), product number 10014, is a water-soluble reducing agent that cleaves disulfide bonds specifically, rapidly reducing them to thiols. TCEP has several advantages over disulfide reducing agents such as dithiothreitol (DTT) and β-mercaptoethanol. These advantages include water solubility, stability in water and non-phosphate aqueous buffers (allowing the preparation of stock solutions, except in aqueous buffers containing phosphate), ease of use, biocompatibility, high reaction specificity, irreversibility of the reaction, and very rapid and efficient reaction kinetics.

Specifications

Unit Size 1000mg, 5000mg, 25g, 100g
Molecular Weight 286.65; single compound
Chemical formula C₉H₁₆CLO₆P
CAS
51805-45-9
Purity > 98%
Spacers
Shipping
Ambient
Typical solubility properties (for additional information contact Customer Support) water.
Storage and handling -20°C; Always let come to room temperature before opening; be careful to limit exposure to moisture and restore under an inert atmosphere; stock solutions can be prepared with dry solvent and kept for several days (freeze when not in use). dPEG® pegylation compounds are generally hygroscopic and should be treated as such. This will be less noticeable with liquids, but the solids will become tacky and difficult to manipulate, if care is not taken to minimize air exposure.

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Description

Tris(2-carboxyethyl)phosphine hydrochloride (commonly known as TCEP or TCEP-HCl), product number QBD-10014, is a water-soluble reducing agent that cleaves disulfide bonds specifically, rapidly reducing them to thiols. TCEP has several advantages over disulfide reducing agents such as dithiothreitol (DTT) and β-mercaptoethanol. These advantages include water solubility, stability in water and non-phosphate aqueous buffers (allowing the preparation of stock solutions, except in aqueous buffers containing phosphate), ease of use, biocompatibility, high reaction specificity, irreversibility of the reaction, and very rapid and efficient reaction kinetics.

Specifications

Unit Size1000mg, 5000mg, 25g, 100g
Molecular Weight286.65; single compound
Chemical formulaC₉H₁₆CLO₆P
CAS
51805-45-9
Purity> 98%
Spacers
 
Shipping
Ambient
Typical solubility properties (for additional information contact Customer Support)water.
Storage and handling-20°C; Always let come to room temperature before opening; be careful to limit exposure to moisture and restore under an inert atmosphere; stock solutions can be prepared with dry solvent and kept for several days (freeze when not in use). dPEG® pegylation compounds are generally hygroscopic and should be treated as such. This will be less noticeable with liquids, but the solids will become tacky and difficult to manipulate, if care is not taken to minimize air exposure.

Documents

References

  1. Greg T. Hermanson, Bioconjugate Techniques, 2nd Edition, Elsevier Inc., Burlington, MA 01803, April, 2008 (ISBN-13: 978-0-12-370501-3; ISBN-10: 0-12-370501-0); pp. 95-97 (protocol), 654.

  2. Greg T. Hermanson, Bioconjugate Techniques, 3rd Edition, Elsevier, Waltham, MA 02451, 2013, ISBN 978-0-12-382239-0; See Chapter 18, Discrete PEG Reagents, pp. 787-821, for a full overview of the dPEG® products.

The post Tris (2-carboxyethyl) phosphine hydrochloride (TCEP) appeared first on VectorLabs.

]]> Click-&-Go™ Magnetic Beads Conjugation Kits https://staging.vectorlabs.com/products/click-go-magnetic-beads-conjugation-kits/ Tue, 19 Sep 2023 20:04:51 +0000 https://staging.vectorlabs.com/?post_type=product&p=22408 Description

Click-&-Go™ Magnetic Beads Conjugation Kit allows antibodies to be covalently attached to high quality 1 μm magnetic particles efficiently, quickly and easily using proprietary technology developed by scientists at Click Chemistry Tools. The conjugation reaction is initiated simply by the activation of the magnetic beads followed by briefly agitating the activated beads with an antibody which becomes attached (via lysine residues) to the magnetic particles. It takes only a few minutes to set up the conjugation, and the covalent conjugate is ready to use within 3 hours or less. Our kit provides enough material for 3 conjugations of 100 μg of antibody to 1.5 mg of the magnetic beads.

Specifications

Unit Size 1 kit
Number of Reactions 3
Storage Conditions 4C
Shipping Conditions Ambient temperature

The post Click-&-Go™ Magnetic Beads Conjugation Kits appeared first on VectorLabs.

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Description

Click-&-Go™ Magnetic Beads Conjugation Kit allows antibodies to be covalently attached to high quality 1 μm magnetic particles efficiently, quickly and easily using proprietary technology developed by scientists at Click Chemistry Tools. The conjugation reaction is initiated simply by the activation of the magnetic beads followed by briefly agitating the activated beads with an antibody which becomes attached (via lysine residues) to the magnetic particles. It takes only a few minutes to set up the conjugation, and the covalent conjugate is ready to use within 3 hours or less. Our kit provides enough material for 3 conjugations of 100 μg of antibody to 1.5 mg of the magnetic beads.

Specifications

Unit Size1 kit
Number of Reactions3
Storage Conditions4C
Shipping ConditionsAmbient temperature

Documents

The post Click-&-Go™ Magnetic Beads Conjugation Kits appeared first on VectorLabs.

]]> Sulfo S-4FB Linker (Water Soluble) https://staging.vectorlabs.com/products/sulfo-s-4fb-crosslinker-water-sol/ Fri, 05 May 2023 21:18:58 +0000 https://staging.vectorlabs.com/?post_type=product&p=14941 Description

The S-4FB heterobifunctional crosslinker is fundamental to the SoluLINK bioconjugation technology. Sulfo-S-4FB reacts with primary amines on proteins (through lysine amino acids) or amino-modified oligonucleotides or surfaces, introducing a 4FB linker that forms stable covalent conjugates with biomolecules possessing HyNic linkers. Sulfo-S-4FB contains a Sulfo-NHS ester, which makes this linker water soluble. No DMF or other organic solvents are necessary to dissolve the linker prior to use.

Specifications

Label/Modifier Type 4FB
Reactivity HyNic
Recommended Storage Desiccated: -15° to -25°C
Applications Antibody Labeling, Antisense/RNAi, Aptamers
Other Name(s) SoluLINK Bioconjugation

The post Sulfo S-4FB Linker (Water Soluble) appeared first on VectorLabs.

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Description

The S-4FB heterobifunctional crosslinker is fundamental to the SoluLINK bioconjugation technology. Sulfo-S-4FB reacts with primary amines on proteins (through lysine amino acids) or amino-modified oligonucleotides or surfaces, introducing a 4FB linker that forms stable covalent conjugates with biomolecules possessing HyNic linkers. Sulfo-S-4FB contains a Sulfo-NHS ester, which makes this linker water soluble. No DMF or other organic solvents are necessary to dissolve the linker prior to use.

Specifications

Label/Modifier Type4FB
ReactivityHyNic
Recommended StorageDesiccated: -15° to -25°C
ApplicationsAntibody Labeling, Antisense/RNAi, Aptamers
Other Name(s)SoluLINK Bioconjugation

Documents

Technical Information

Introduction to SoluLINK Bioconjugation Technology

This core technology is based on the formation of a covalent bond formed from an aromatic hydrazine and an aromatic aldehyde. S-HyNic 1 (succinimidyl 6-hydrazinonicotinate acetone hydrazone, SANH) is used to incorporate aromatic hydrazine linkers on biomolecules. S-HyNic is an amino-reactive reagent that directly converts amino groups on biomolecules and surfaces to HyNic groups. S-4FB 2 (succinimidyl 4-formylbenzoate, SFB) is used to convert amino groups to aromatic aldehydes (4-formylbenzamide (4FB) groups). Addition of a HyNic- modified biomolecule to a 4FB-modified biomolecule or surface directly leads to the formation of the conjugate (Figure 1). The conjugate bond is stable to 92℃ and pH 2.0- 10.0. The recommended pH for antibody conjugation is 6.0. Unlike thiol-based conjugation protocols where reducing reagents are required that that can compromise the activity of proteins by cleaving disulfide bonds, the HyNic-4FB conjugation couple leaves disulfide bonds intact. No oxidants, reductants or metals are required in the preparation of conjugate.

S 1008 F1 jpg

Figure 1: Schematic representation of the SoluLINK bioconjugation chemistry where an antibody is modified with S-HyNic to incorporate HyNic groups and a second protein is modified with S-4FB to incorporate 4FB groups. Conjugate is formed directly by simply mixing the HyNic-modified antibody with the 4FB-modified proteins.

Further enhancing the many advantages of the HyNic/4FB conjugation couple is the discovery by Dirksen et al. that showed that aniline catalyzes the formation of this Schiff’s base. This is especially effective for large biomolecule conjugations. In the case of antibody-protein conjugations the addition of 10 mM TurboLINK Catalyst Buffer (aniline) to the reaction mixture converts >95% of the antibody to conjugate in ~2 hours using 1-2 mole equivalents of second protein.

The HyNic-4FB conjugation couple is chromophoric- the conjugate bond absorbs at 354 nm and has a molar extinction coefficient of 29,000 L/(mol*cm). This allows (1) real time spectrophotometric monitoring of a conjugate reaction, (2) ability to visualize the conjugate during chromatographic purification using a UV or photodiode array detector and (3) quantification of conjugation.

Legal Information

SoluLINK® Bioconjugation For Research Use Only. Not for use in diagnostic procedures. For additional licensing restrictions, please see the license agreement at vectorlabs.com/solulink-research-license.

Products are for research use only, not for use in diagnostic or therapeutic procedures or for use in humans. Products are not for resale without express written permission of Seller. No license under any patent or other intellectual property right of Seller or its licensors is granted or implied by the purchase unless otherwise provided in writing.

The post Sulfo S-4FB Linker (Water Soluble) appeared first on VectorLabs.

]]> Protein–Oligo Conjugation Kit https://staging.vectorlabs.com/products/protein-oligo-conjugation-kit/ Thu, 04 May 2023 04:57:33 +0000 https://staging.vectorlabs.com/?post_type=product&p=15160 Description

The Protein-Oligo Conjugation Kit is designed to easily and efficiently prepare two separate protein-oligo conjugates. This kit is flexible so that researchers with little or no conjugation experience can make their own custom protein-oligo conjugates to suit their research needs. It includes all of the necessary components, including S-HyNic and S-4FB, for the rapid and specific crosslinking of any protein with any oligo from 20 to 100 nucleotides in length.

The molecular weight range for proteins to be conjugated with this kit is 25,000 to 900,000 Daltons. Protein amounts from 50 – 650 µg at a concentration of 1 – 5 mg/mL in a volume of 50 – 130 µL are suitable for conjugation.

Specifications

Conjugation Targets Protein
Label/Modifier Type Oligonucleotide
Reactivity Amine
Recommended Storage 2° – 8°C – Do Not Freeze
Applications Antibody Labeling, In Situ Proximity Ligation

Kit Components

  • S-HyNic (2 X 1 mg)
  • S-4FB (2 x 1mg)
  • 10X Modification Buffer (1.5 mL)
  • 10X Conjugation Buffer (1.5 mL)
  • 10X TurboLINK™ Catalyst Buffer (1.5 mL)
  • 7kDa MWCO, 0.5 mL Thermo Scientific™ Zeba™ Column (4)
  • Anhydrous DMF (1.5 mL)
  • 2-Hydrazinopyridine (2-HP) (0.5 mL)
  • 2-Sulfobenzaldehyde (2-SB) (0.5 mL)
  • 7kDa MWCO 2 mL Zeba™ Column (2)
  • 10X PBS (1.5 mL)
  • 2 mL Collection Tube (12)
  • Oligo Resuspension Solution (1.0 mL)

The post Protein–Oligo Conjugation Kit appeared first on VectorLabs.

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Description

The Protein-Oligo Conjugation Kit is designed to easily and efficiently prepare two separate protein-oligo conjugates. This kit is flexible so that researchers with little or no conjugation experience can make their own custom protein-oligo conjugates to suit their research needs. It includes all of the necessary components, including S-HyNic and S-4FB, for the rapid and specific crosslinking of any protein with any oligo from 20 to 100 nucleotides in length.

The molecular weight range for proteins to be conjugated with this kit is 25,000 to 900,000 Daltons. Protein amounts from 50 – 650 µg at a concentration of 1 – 5 mg/mL in a volume of 50 – 130 µL are suitable for conjugation.

Specifications

Conjugation TargetsProtein
Label/Modifier TypeOligonucleotide
ReactivityAmine
Recommended Storage2° – 8°C – Do Not Freeze
ApplicationsAntibody Labeling, In Situ Proximity Ligation

Kit Components

  • S-HyNic (2 X 1 mg)
  • S-4FB (2 x 1mg)
  • 10X Modification Buffer (1.5 mL)
  • 10X Conjugation Buffer (1.5 mL)
  • 10X TurboLINK™ Catalyst Buffer (1.5 mL)
  • 7kDa MWCO, 0.5 mL Thermo Scientific™ Zeba™ Column (4)
  • Anhydrous DMF (1.5 mL)
  • 2-Hydrazinopyridine (2-HP) (0.5 mL)
  • 2-Sulfobenzaldehyde (2-SB) (0.5 mL)
  • 7kDa MWCO 2 mL Zeba™ Column (2)
  • 10X PBS (1.5 mL)
  • 2 mL Collection Tube (12)
  • Oligo Resuspension Solution (1.0 mL)

Documents

Product FAQs

The Protein-Oligo Conjugation Kit (S-9011) was designed with more flexibility in mind to allow conjugation of any protein greater than about 20 kDa, to an oligonucleotide. No purification material is included in this kit because there are so many different proteins that can be conjugated. This kit also allows for a variable amount of protein to be coupled (from about 50µg up to 650µg).

The Antibody – Oligonucleotide All-in-One Conjugation Kit (A-9202) was designed specifically for simple and reproducible coupling of an oligo to a fixed amount of antibody (100µg). All kit components have been optimized around this amount, which reduces the number of calculations involved and reduces variability in the process. This kit does include purification so the final conjugate is very pure (i.e., no free antibody or oligo remains in the final product), which allows kit usage in very sensitive assays. Since this kit is designed for antibodies, purification is accomplished using a resin that binds to all mammalian IgG antibody isotypes. Yields from this kit are typically 30-60% based on the amount of starting antibody. Longer oligos (60-mers and up) tend to have a lower yield (in the 20-40% range) due to steric hinderance of the antibody binding to the resin.

Citations

Technical Information

I. Introduction

a. Product Description

The Protein-Oligo Conjugation Kit is designed to conjugate a protein with an oligonucleotide. It includes all of the necessary components and protocols for easy and specific crosslinking of any protein with any amino-oligo from 20 to 100 bases in length. This kit is flexible so that researchers with little or no conjugation experience can make their own custom protein-oligo conjugate to suit their needs.

SoluLINK bioconjugation technology converts more than 95% of protein to conjugate when four mole equivalents of oligo are added. High conversion rates, coupled with the unique UV-traceable bond formed during crosslinking, allows for easy purification and identification of the conjugate from the excess oligo using size exclusion purification methods such as HPLC.

b. SoluLINK Bioconjugation Technology

The Protein-Oligo Conjugation Kit uses the superior SoluLINK bioconjugation technology to prepare protein-oligonucleotide conjugates in 3 easy-to-perform steps (Figure 1). The first step is the modification of the oligo with our 4FB crosslinker, followed by the formation of the HyNic modified protein. Finally, simple mixing of the two modified biomolecules will result in the formation of a stable, UV-traceable bond formed by the reaction of a HyNic modified protein with a 4FB modified oligonucleotide.

This technology has many practical advantages compared to previous crosslinking methods:

1. The reaction is high yielding. Routine yields of conjugate are 50-80% based on starting protein.

2. The reaction is efficient: Only 3-4 mole equivalents of oligo are necessary for the protein, >90% of the protein is conjugated.

3. The conjugate bond is extremely stable: The conjugate bond is stable to 92℃ and pH 2.0-10.0.

4. The reaction conditions are mild and do not cause any protein denaturation: unlike thiol-based conjugation protocols, where reducing reagents are required that can compromise the activity of proteins by cleaving disulfide bonds, the HyNic-4FB conjugation couple leaves disulfide bonds intact. No metals, oxidation or reducing reagents are required.

S 9011 F1 jpg 

Figure 1: Schematic representation of the three step process to prepare an antibody-oligonucleotide conjugate using SoluLINK Bioconjugation technology. Initially an antibody is modified with S-HyNic to incorporate HyNic groups and subsequently the HyNic-modified antibody is reacted with a 4FB-modified oligonucleotide.

5. The conjugation is traceable spectrophotometrically. The HyNic-4FB conjugate bond is UV-traceable; it absorbs at 354 nm and has a molar extinction coefficient of 29,000 L/(mol*cm).

6. The modifications of both the HyNic linker on the protein and the 4FB linker on the oligonucleotide are quantifiable using colorimetric assays. The reproducibility of any reaction is facilitated by accurate characterization of all components. The Molar Substitution Ratio (MSR) of linker groups, i.e. the number of HyNic linkers per protein, can be quantified colorimetrically. This kit contains all the reagents necessary to determine the MSRs for both the protein and the oligo.

II. Protein-Oligonucleotide Conjugates: A Review

The diversity and specificity of proteins combined with the specificity of hybridization of oligonucleotides results in unlimited numbers of specific protein detection reagents whose applications are addressed below.

The use of oligo-protein conjugates was initially demonstrated by Sano et al. for protein detection by a technique called immuno-PCR (Polymerase Chain Reaction) where a 100-mer oligo/antibody conjugate was allowed to bind to its ligand and amplified by PCR demonstrating extremely sensitive protein detection. Since this initial publication there has been a need for a straight forward, efficient and high yielding method for the preparation of these conjugates.

The first generation immuno-PCR protocol was plagued by high background due to non-specific binding of the conjugate and the extreme sensitivity of PCR. This has been overcome by the Proximal Ligation Assay (PLA) developed by Fredriksson and Lundegren. In the PLA assay, two antibodies to different epitopes are conjugated to a 40-mer 5’-phosphorylated oligonucleotide through the 3’-end and 60-mer oligonucleotide conjugated through its 5’-terminus. The two oligo/antibody conjugates are incubated with the sample, allowed to bind to their respective epitopes, the mixture is washed and then incubated with a ‘splint’ oligo that hybridizes across the two oligonucleotides that is subsequently ligated. Following ligation, PCR is performed on the ligated oligo generating a quantifiable signal. In subsequent work the oligo/antibody conjugates used by Fredriksson et al. and others used conjugates using the HyNic-4FB conjugation method. Kozlov et al also describe the use of oligonucleotide/antibody conjugates for the sensitive detection of proteins.

Additionally, oligonucleotide/antibody conjugates have been used for capture of antigens and subsequent addressing to antibody arrays for multiplex detection of proteins as well for cell sorting on the same diagnostic platform. Oligonucleotide/protein conjugates have been also been used in vaccines to increase adjuvanticity using CpG oligonucleotide/protein conjugates.

III. Accessing 4FB-Modified Oligonucleotides

Stable and disulfide-cleavable 4FB oligonucleotides can be obtained in several ways:

  1. 5’-4FB oligonucleotide

    a. 4FB-phosphoramidite: 4FB-Phosphoramidite (1; Figure 2) is available for incorporation of 5’-4FB groups during oligonucleotide solid phase synthesis. Standard coupling protocols are used and the yields are similar to any amino modifier.

    b. 5’-amino oligonucleotides: 5’-amino oligonucleotides may be converted to 5’-4FB modified oligonucleotides in a straightforward high yielding modification step with S-4FB (2; Figure 2).

    The Protein-Oligo Conjugation Kit includes S-4FB and all the reagents and materials required to convert a 5’-amino oligonucleotide to a 5’-4FB-oligonucleotide.

  2. 3’-4FB oligonucleotide:
    3’-Amino oligonucleotides are converted to 3’-4FB modified oligonucleotides in an easy, high yielding modification step with S-4FB (2; Figure 2).
    The Protein-Oligo Conjugation Kit includes S-4FB and all the reagents and disposables required to convert a 3’-amino oligonucleotide to a 3’-4FB-oligonucleotide.
  3. 5’- and 3’-4FB disulfide-cleavable oligonucleotides: 5’- and 3’-amino oligonucleotides may be converted to disulfide-cleavable oligonucleotides using S-SS-4FB (3; Figure 2) in an easy, high yielding modification step.

    S 9011 F2 jpg

Figure 2: Schematic representation of the conversion of an amino-modified oligonucleotide to a 4FB-oligonucleotide with S-4FB (2) (top) and structures of 4FB-phosphoramidite (1) and S-SS-4FB (3), the reagent used to convert an amino-oligonucleotide to a 4FB-SS-oligonucleotide.

IV. The Keys to Successful Conjugation

The following are three crucial requirements that must be fulfilled for a reproducibly successful preparation of a protein-oligonucleotide conjugate using the SoluLINK bioconjugation technology:

  1. Desalting: Prior to modification, the starting protein must be thoroughly desalted, removing all amine contaminants, and exchanged into 1X Modification Buffer.
  2. Protein concentration: The recommended concentration of the protein (1–5mg/ml) must be adhered to in all steps.
  3. Molar substitution ratio: The molar ratio of the HyNic on the protein and the 4FB on the oligo must be determined and within the desired range before continuing to the next step.

Legal Information

SoluLINK® Bioconjugation For Research Use Only. Not for use in diagnostic procedures. For additional licensing restrictions, please see the license agreement at vectorlabs.com/solulink-research-license.

Products are for research use only, not for use in diagnostic or therapeutic procedures or for use in humans. Products are not for resale without express written permission of Seller. No license under any patent or other intellectual property right of Seller or its licensors is granted or implied by the purchase unless otherwise provided in writing.

Zeba and Thermo Scientific are trademarks of Thermo Fisher Scientific Inc.

The post Protein–Oligo Conjugation Kit appeared first on VectorLabs.

]]> Protein–Protein Conjugation Kit https://staging.vectorlabs.com/products/protein-protein-conjugation-kit/ Thu, 04 May 2023 04:05:06 +0000 https://staging.vectorlabs.com/?post_type=product&p=15011 Description

The Protein-Protein Conjugation Kit is designed to easily and efficiently conjugate any two proteins. This kit is flexible so that researchers with little or no bioconjugation experience can make their own custom protein-protein conjugates to suit their research needs. It includes all of the necessary components, including S-HyNic and S-4FB, for the rapid and specific crosslinking of any two proteins.

The molecular weight range for proteins to be conjugated with this kit is 25,000 to 900,000 Daltons. to The molecular weight range for proteins to be conjugated with this kit is 25–950 kDa.

Specifications

Conjugation Targets Protein
Label/Modifier Type Protein
Reactivity Amine
Recommended Storage 2° – 8°C – Do Not Freeze
Applications Antibody Labeling, In Situ Proximity Ligation

Kit Components

  • S-HyNic (2 x 1.0 mg)
  • S-4FB (2 x 1.0 mg)
  • 10X Modification Buffer (1.5 mL)
  • 10X Conjugation Buffer (1.5 mL)
  • 10X TurboLINK™ Catalyst Buffer (1.5 mL)
  • 7kDa, 0.5 mL Thermo Scientific™ Zeba™ Column (10)
  • Anhydrous DMF (2 x 1.5 mL)
  • 2-Hydrazinopyridine (2-HP) reagent (0.5 mL)
  • 0.5mM 2-Sulfobenzaldehyde (2-SB) (0.5 mL)
  • 2 mL Collection Tube (10)
  • 7kDa, 2 mL Zeba™ Column (2)
  • 10X PBS (1.5 mL)

The post Protein–Protein Conjugation Kit appeared first on VectorLabs.

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Description

The Protein-Protein Conjugation Kit is designed to easily and efficiently conjugate any two proteins. This kit is flexible so that researchers with little or no bioconjugation experience can make their own custom protein-protein conjugates to suit their research needs. It includes all of the necessary components, including S-HyNic and S-4FB, for the rapid and specific crosslinking of any two proteins.

The molecular weight range for proteins to be conjugated with this kit is 25,000 to 900,000 Daltons. to The molecular weight range for proteins to be conjugated with this kit is 25–950 kDa.

Specifications

Conjugation TargetsProtein
Label/Modifier TypeProtein
ReactivityAmine
Recommended Storage2° – 8°C – Do Not Freeze
ApplicationsAntibody Labeling, In Situ Proximity Ligation

Kit Components

  • S-HyNic (2 x 1.0 mg)
  • S-4FB (2 x 1.0 mg)
  • 10X Modification Buffer (1.5 mL)
  • 10X Conjugation Buffer (1.5 mL)
  • 10X TurboLINK™ Catalyst Buffer (1.5 mL)
  • 7kDa, 0.5 mL Thermo Scientific™ Zeba™ Column (10)
  • Anhydrous DMF (2 x 1.5 mL)
  • 2-Hydrazinopyridine (2-HP) reagent (0.5 mL)
  • 0.5mM 2-Sulfobenzaldehyde (2-SB) (0.5 mL)
  • 2 mL Collection Tube (10)
  • 7kDa, 2 mL Zeba™ Column (2)
  • 10X PBS (1.5 mL)

Documents

Technical Information

The ChromaLINK Reaction:

ChromaLINK bioconjugation technology is based on the formation of a stable bis-arylhydrazone formed from an aromatic hydrazine and an aromatic aldehyde. S-HyNic (succinimidyl 6-hydrazinonicotinate acetone hydrazone, SANH) is used to incorporate aromatic hydrazine moieties on biomolecules. S-HyNic is an amine-reactive reagent that directly converts amino groups on biomolecules and surfaces to HyNic groups. S-4FB (succinimidyl 4-formylbenzoate, SFB) is used to convert amino groups to aromatic aldehydes (4-formylbenzamide (4FB) groups). Addition of a HyNic-modified biomolecule to a 4FB-modified biomolecule or surface directly leads to the formation of the conjugate (Figure 1). The bis-arylhydrazone bond is stable up to 92℃ and pH 2.0-10.0. Due to lability of the immunoreactivity of antibodies at low pH, i.e. < 5.0, the recommended pH for antibody conjugation is 6.0. Unlike thiol-based conjugation protocols where reducing reagents are required that can compromise the activity of proteins by cleaving disulfide bonds, the HyNic-4FB conjugation couple leaves disulfide bonds intact. No oxidants, reducing agents, or metals are required in the preparation of conjugate.

S 9010 F1 jpg

Figure 1: Linking chemistry behind ChromaLINK bioconjugation technology.

Fastest, most efficient:

Further enhancing the many advantages of the HyNic/4FB conjugation couple is the discovery by Dirksen et al. that showed aniline catalyzes the formation of this Schiff’s base. This is especially effective for large biomolecule conjugations. In the case of antibody-protein conjugations the addition of 10 mM aniline to the reaction mixture converts >95% of the antibody to conjugate in 2 hours using 1-2 mole equivalents of second protein.

Traceable modification:

Reproducibility of any reaction is dependent on accurate characterization of all components. As both HyNic and 4FB are aromatic, their incorporation can be readily quantified using colorimetric assays.

Traceable conjugation:

The HyNic-4FB conjugate bond is chromophoric. It absorbs light at 354 nm and has a molar extinction coefficient of 29,000 L/(mol*cm).

Furthermore, compared to previous methods, the HyNic/4FB technology offers the following practical advantages:

1)  The reaction goes to completion: In all previous bi-functional linker-based conjugations, the reaction never went to completion, i.e. there was always unconjugated limiting protein in the final product. The HyNic-4FB conjugation couple catalyzed by aniline yields more than 95% conjugate.

2)  The reaction is efficient: The reaction is very stoichiometrically efficient as input of only 1-2 moles of second protein/mole first protein is required for complete conversion to conjugate.

3)  The conjugate bond is extremely stable: the bis-arylhydrazone conjugate bond is stable up to 92℃ and pH 2.0-10.0.

4)  The reaction conditions are extremely mild and do not cause antibody denaturation: unlike thiol-based conjugation protocols where reducing reagents are required that can compromise the activity of proteins by cleaving disulfide bonds, the HyNic-4FB conjugation couple leaves disulfide bonds intact. No metals, oxidizing, or reducing reagents are required.

5)  The conjugation is traceable spectrophotometrically: the HyNic-4FB conjugate bond is chromophoric; it absorbs light at 354 nm and has a molar extinction coefficient of 29,000 L/(mol*cm).

6)  The modifications of both the HyNic moiety on the protein and the 4FB moiety on the protein is quantifiable using a colorimetric assay: the reproducibility of any reaction is dependent on accurate characterization of all components. The Molar Substitution Ratio (MSR; i.e. the number of HyNic groups incorporated per protein) can be quantified colorimetrically as a reaction with 2-sulfobenzaldehyde yields a chromophoric product that absorbs at 350 nm with a molar extinction coefficient of 28,500 L/(mol*cm). The MSR of 4FB groups can be determined colorimetrically by its reaction with 2-hydrazinopyridine forming a hydrazone that absorbs at 348 nm with a molar extinction coefficient of 24,500 L/(mol*cm). This kit contains all the reagents necessary to determine both MSRs. Procedures to guide users through this process are given in the protocol below.

The Keys to Successful Conjugation

The following are three crucial requirements that must be fulfilled for a reproducibly successful preparation of a protein-protein conjugate using the SoluLINK bioconjugation technology:

1. Desalting: prior to modification, the starting proteins must be thoroughly desalted, removing all amine contaminants and exchanging the proteins into 1X Modification Buffer.

2. Protein concentration: the recommended protein concentrations must be adhered to in all steps.

3. Molar substitution ratio: the molar ratio of HyNic on the protein and 4FB on the protein must be determined and within the desired range before continuing to the next step.

Legal Information

SoluLINK® Bioconjugation For Research Use Only. Not for use in diagnostic procedures. For additional licensing restrictions, please see the license agreement at vectorlabs.com/solulink-research-license.

Products are for research use only, not for use in diagnostic or therapeutic procedures or for use in humans. Products are not for resale without express written permission of Seller. No license under any patent or other intellectual property right of Seller or its licensors is granted or implied by the purchase unless otherwise provided in writing.

Zeba and Thermo Scientific are trademarks of Thermo Fisher Scientific Inc.

The post Protein–Protein Conjugation Kit appeared first on VectorLabs.

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