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MAL-dPEG®₄-Glu(TFP ester)-NH-dPEG®₄-Glu(TFP ester)-NH-m-dPEG®₂₄

MAL-dPEG®₄-Glu(TFP ester)-NH-dPEG®₄-Glu(TFP ester)-NH-m-dPEG®₂₄

Click this button to learn more about our Sidewinder™ line of products.MAL-dPEG®4-Glu(TFP ester)-NH-dPEG®4-Glu(TFP ester)-NH-m-dPEG®24, product number 11626, is a novel, patent-pending Sidewinder™ product from Quanta BioDesign that permits attachment of hydrophobic groups on the sidearms of two glutamic acid moieties. Short hydrophilic spacers separate the glutamates, and a long hydrophilic dPEG® unit terminates the construct. A sulfhydryl-reactive maleimide group provides an attachment point for the construct to another molecule, such as a protein or peptide. Tetrafluorophenyl esters functionalize the two glutamate units along the Sidewinder™ backbone.
What is dPEG®?The dPEG® tradename describes Quanta BioDesign's patented brand of monodispersed PEGylation reagents. Quanta BioDesign's dPEG® products are high-purity, single molecular weight PEG products with discrete chain lengths. (The "d" in the dPEG® name stands for "discrete.") Our products have no dispersity (Ð = 1), unlike traditional PEG products, which are dispersed polymers.Furthermore, we do not purify our products from a polymeric mixture. Instead, we synthesize dPEG® products from very high-purity starting materials using the traditional tools of synthetic organic chemistry. The result is a well-defined, monodisperse PEG product with high purity and superior performance to a dispersed PEG product. At Quanta BioDesign, we call this "the dPEG® difference."Learn more!What is dPEG®?Frequently Asked Questions (about dPEG® products)What is a Sidewinder™ product?The Sidewinder™ line of products is a novel, patent-pending product line that permits attachment of a hydrophobic drug or other small molecules on the sidearm of an amino acid with dPEG® linkers on either side of the amino acid imparting hydrophilicity, increasing hydrodynamic volume, and protecting from proteolysis. This unique line of products allows users to optimize biodistribution, modulate cell trafficking and internalization, extend serum half-life, and reduce or eliminate immunogenicity.All Sidewinder™ products consist of a functional group for attachment, a short hydrophilic spacer, an amino acid attachment point for functional groups such as small molecule drugs, and a long hydrophilic, non-immunogenic spacer that protects the functional group on the amino acid's sidearm. One typical use for a Sidewinder™ product is creating antibody-drug conjugates (ADCs) with a high drug-antibody ratio (DAR).Importantly, Sidewinder™ products have nearly infinite variability. The spacer length between the terminal reactive group and the amino acid can be as long or short as desired. The amino acid can be varied to include any functionality desired on the sidearm. The terminal protective dPEG® moiety varies in both length and terminal functionality. Also, Sidewinder™ arms can contain multiple amino acids with different functional groups on the sidearms, allowing for highly complex supramolecular constructs.For more information about our Sidewinder™ products, please see Sidewinder™ dPEG® Constructs. To learn more about our dPEG® products, please click the following links:What is dPEG®?Frequently Asked Questions (about dPEG® products)Bulk Quantities Are AvailableIf you need bulk product in a larger package size than our standard sizes, please contact us for a quote. Our commercial capabilities permit us to manufacture this product at any scale that you need.Buy It Now!To get started with your purchase of MAL-dPEG®4-Glu(TFP ester)-NH-dPEG®4-Glu(TFP ester)-NH-m-dPEG®24, product number 11626, please click the "Add to Cart" button now.
MAL-dPEG®₂₄-amido-dPEG®₂₄-TFP ester

MAL-dPEG®₂₄-amido-dPEG®₂₄-TFP ester

TFP_Esters_Art2MAL-dPEG®24-amido-dPEG®24-TFP ester, product number 11303, is a monodisperse, crosslinking PEGylation reagent that joins sulfhydryl groups to amines through a single molecular weight, discrete PEG (dPEG®) chain. The dPEG® crosslinker is 158 atoms long (183.5 Å). At pH 6.5 – 7.5, the maleimido group reacts specifically with sulfhydryl (thiol) groups to form a thioether bond. The 2,3,5,6-tetrafluorophenyl (TFP) ester reacts with free amines to form amide bonds. Compared with N-hydroxysuccinimide (NHS) esters, TFP esters are more reactive and hydrolytically stable in aqueous buffer. The water-soluble, nonimmunogenic dPEG® spacer increases the hydrophilicity and hydrodynamic volume of conjugates made with this product.
Crosslinking Reactions with PEGylation ReagentsOne of the most popular, most useful crosslinking reactions in bioconjugate chemistry[1],[2] is the conjugation of free amines to free thiols. These reactions require heterobifunctional reagents that bridge the two groups. Typical crosslinkers are short and hydrophobic. Quanta BioDesign's dPEG® crosslinking products are water-soluble, amphiphilic, single molecular weight PEG compounds with discrete chain lengths.Conventional hydrophobic crosslinking reagents frequently trigger aggregation and precipitation of the conjugates made from them. Moreover, these hydrophobic crosslinkers may contribute to non-specific binding problems in some assays. These problems do not happen with our water-soluble, non-immunogenic dPEG® crosslinkers.Traditional PEGylation reagents are made from dispersed polymers. These polymeric reagents are intractably complex mixtures of different PEG chain lengths and molecular weights. This complexity creates difficulties in the analysis of conjugates. Quanta BioDesign's dPEG® products have no dispersity (Ð = 1). Each dPEG® product consists of a discrete chain of PEG with a single molecular weight. The uniform nature of our dPEG® products eliminates one of the most vexing analytical difficulties faced by users of traditional polymer PEG products.Learn more about dPEG® products!What is dPEG®?Frequently Asked Questions (about dPEG® products)Why Use a TFP ester?TFP esters are more stable in aqueous buffers than NHS esters. Moreover, TFP esters have higher reactivity with free amines compared to NHS esters.[3] NHS esters hydrolyze readily in water or aqueous buffer. As the pH increases, the hydrolysis rate of the NHS ester increases.[4] In 2017, a study by J. Wang, et al., on the performance of fluorophenyl esters concluded, "With regards to PEGylation, the TFP ester performed better than NHS ester."[5] In-house research at Quanta BioDesign confirms the superior performance of TFP esters over NHS esters.Learn more about TFP esters!TFP Esters Have More Hydrolytic Stability and Greater Reactivity Than NHS EstersHow Do I Use MAL-dPEG®24-amido-dPEG®24-TFP ester?TFP esters react under the same conditions as NHS esters. However, the optimal pH range for TFP esters (7.5 – 8.0) is slightly higher than for NHS esters (7.0 – 7.5).5 Amide bond formation between the TFP-activated propionic acid group of MAL-dPEG®24-amido-dPEG®24-TFP ester and a free amine will be slightly slower at a suboptimal pH compared to the reaction rate within the optimum pH range.The maleimide end of MAL-dPEG®24-amido-dPEG®24-TFP ester, product number 11303, reacts optimally with a sulfhydryl at pH 6.5 – 7.5. Conduct the conjugation at the lowest reasonable pH within this range. Above pH 7.5, free amines compete with free thiols at the maleimide reaction site, which may confound the data. Moreover, at higher pH values, the maleimide ring may open to form unreactive maleamic acid.[6]Learn more about the maleimide-thiol reaction!Maleimide Reaction Chemistry.What Applications Use MAL-dPEG®24-amido-dPEG®24-TFP ester?MAL-dPEG®24-amido-dPEG®24-TFP ester, product number 11303, can be used the same way and in the same applications as the equivalent NHS esters. Possible uses for this product include the following:
  • Increasing the water solubility and hydrodynamic volume of biomolecules;
  • Constructing antibody-drug conjugates (ADCs);
  • Tethering antibodies to atomic force microscopy (AFM) probes;
  • Coating nanoparticle surfaces;
  • Building supramolecular constructs; and,
  • Conjugating the TFP ester end of the molecule to a liposomal surface and then attaching a small molecule drug, peptide, or antibody to the maleimide group for targeted delivery of a diagnostic or therapeutic package.
How can you use this product in your next product development project?Do You Offer Commercial Scale Quantities of MAL-dPEG®24-amido-dPEG®24-TFP ester?Yes, we do. If you need bulk product in a larger package size than our standard sizes, please contact us for a quote. Our commercial capabilities permit us to manufacture this product at any scale that you need.Buy Now!Hydrophobic crosslinkers create more problems than they solve. Traditional disperse polymer PEG crosslinkers add unnecessary analytical complexity to conjugates that incorporate them.So, stop using inferior products!Start using single molecular weight dPEG® crosslinkers and discover the dPEG® difference. To get started, please click the "Add to Cart" button now to order MAL-dPEG®24-amido-dPEG®24-TFP ester, product number 11303.Application References:[1] Hermanson, G. T. Chapter 6, Heterobifunctional Crosslinkers. In Bioconjugate Techniques, 3rd ed.; Academic Press: New York, NY, 2013; pp 299–340, specifically page 300. Many scientists engaged in bioconjugation work consider Greg Hermanson's book to be the definitive reference on the subject. Click here now to read a review of Greg's book and to purchase it.[2] Hermanson, G. T. Chapter 18, PEGylation and Synthetic Polymer Modification. In Bioconjugate Techniques, 3rd ed.; Academic Press: New York, NY, 2013; pp 787–838, specifically page 794.[3] Hermanson, G. T. Chapter 3, The Reactions of Bioconjugation. In Bioconjugate Techniques; Academic Press: New York, NY, 2013; pp 229–258, specifically page 239.[4] Ibid, page 234.[5] Wang, J.; Zhang, R.-Y.; Wang, Y.-C.; Chen, X.-Z.; Yin, X.-G.; Du, J.-J.; Lei, Z.; Xin, L.-M.; Gao, X.-F.; Liu, Z.; et al. Polyfluorophenyl Ester-Terminated Homobifunctional Cross-Linkers for Protein Conjugation. Synlett 2017, 28 (15), 1934–1938. https://doi.org/10.1055/s-0036-1590974.[6] Hermanson, G. T. Chapter 6, op. cit., page 304.
MAL-dPEG®₄-TFP ester

MAL-dPEG®₄-TFP ester

TFP_Esters_Art2MAL-dPEG®4-TFP ester, product number 10551, is a crosslinking reagent that joins free amines to free thiols (sulfhydryl groups). The sulfhydryl groups react with a maleimido group via a Michael addition reaction. The amines form amide bonds with the crosslinker by nucleophilic substitution of the 2,3,5,6-tetrafluorophenyl (TFP) ester of the terminal propionic acid group. The maleimido and TFP functional groups on the crosslinking compound sit at either end of a short, discrete chain of polyethylene glycol (hence, dPEG®). The single molecular weight dPEG® spacer is 22 atoms (24.1 Å) long.

Crosslinking Reactions

One of the most popular, most useful crosslinking reactions in bioconjugate chemistry[1],[2] is the conjugation of free amines to free thiols. These reactions require heterobifunctional reagents that bridge the two groups. Typical crosslinkers are hydrophobic. Quanta BioDesign's dPEG® crosslinking products are water-soluble, amphiphilic, single molecular weight PEG compounds with discrete chain lengths.With conventional hydrophobic crosslinking reagents, aggregation and precipitation of the conjugates occur frequently. These problems do not happen with our water-soluble, non-immunogenic dPEG® crosslinkers. For more information about our dPEG® products, please see our "What is dPEG®?" page. Also, click here for answers to our most frequently asked questions.

TFP Esters are Superior to NHS esters

TFP esters are more stable in aqueous buffers than N-hydroxysuccinimidyl (NHS) esters. Moreover, TFP esters have higher reactivity with free amines than NHS esters.[3] NHS esters hydrolyze readily in water or aqueous buffer. As the pH increases, the hydrolysis rate of the NHS ester increases.[4] In 2017, a study by J. Wang, et al., on the performance of fluorophenyl esters concluded, "With regards to PEGylation, the TFP ester performed better than NHS ester."[5] In-house research at Quanta BioDesign confirms the superior performance of TFP esters over NHS esters.

How to Use MAL-dPEG®4-TFP ester

TFP esters react under the same conditions as NHS esters. However, the optimal pH range for TFP esters (7.5 – 8.0) is slightly higher than for NHS esters (7.0 – 7.5).5 Amide bond formation between the TFP-activated propionic acid group of MAL-dPEG®4-TFP ester and a free amine will be slightly slower at a suboptimal pH compared to the reaction rate within the optimum pH range.The maleimide end of MAL-dPEG®4-TFP ester, product number 10551, reacts optimally with a sulfhydryl at pH 6.5 – 7.5. Conduct the conjugation at the lowest reasonable pH within this range. Above pH 7.5, free amines compete with free thiols at the maleimide reaction site, which may confound the data. Moreover, at higher pH values, the maleimide ring may open to form unreactive maleamic acid.[6] For details about maleimide-thiol reaction chemistry, please click here.

Uses of MAL-dPEG®4-TFP ester

MAL-dPEG®4-TFP ester, product number 10551, can be used the same way and in the same applications as the equivalent NHS esters. Possible uses for this product include the following:
  • Coating nanoparticle surfaces;
  • Tethering antibodies to atomic force microscopy (AFM) probes;
  • Constructing antibody-drug conjugates (ADCs);
  • Adding flexibility and water solubility to a peptide;
  • Increasing the water solubility and hydrodynamic volume of hydrophobic biomolecules;
  • Building supramolecular constructs; and,
  • Conjugating the TFP ester end of the molecule a liposomal surface and then using the free maleimide end of the molecule to attach a small molecule drug, peptide, or antibody for targeted delivery of a diagnostic or therapeutic package.
How do you plan to utilize this product's potential?

Bulk Scale Synthesis of MAL-dPEG®4-TFP ester is Available

If you need bulk product in a larger package size than our standard sizes, please contact us for a quote. Our commercial capabilities permit us to manufacture this product at any scale that you need.Buy Now!Hydrophobic crosslinkers create more problems than they solve. Traditional disperse polymer PEG crosslinkers add unnecessary analytical complexity to conjugates that incorporate them.So, stop using inferior products!Start using single molecular weight dPEG® crosslinkers and discover the dPEG® difference. To get started, please click the "Add to Cart" button now to order MAL-dPEG®4-TFP ester, product number 10551.Application References:[1] Hermanson, G. T. Chapter 6, Heterobifunctional Crosslinkers. In Bioconjugate Techniques, 3rd ed.; Academic Press: New York, NY, 2013; pp 299–340, specifically page 300. Many scientists engaged in bioconjugation work consider Greg Hermanson's book to be the definitive reference on the subject. Click here now to read a review of Greg's book and to purchase it.[2] Hermanson, G. T. Chapter 18, PEGylation and Synthetic Polymer Modification. In Bioconjugate Techniques, 3rd ed.; Academic Press: New York, NY, 2013; pp 787–838, specifically page 794.[3] Hermanson, G. T. Chapter 3, The Reactions of Bioconjugation. In Bioconjugate Techniques; Academic Press: New York, NY, 2013; pp 229–258, specifically page 239.[4] Ibid, page 234.[5] Wang, J.; Zhang, R.-Y.; Wang, Y.-C.; Chen, X.-Z.; Yin, X.-G.; Du, J.-J.; Lei, Z.; Xin, L.-M.; Gao, X.-F.; Liu, Z.; et al. Polyfluorophenyl Ester-Terminated Homobifunctional Cross-Linkers for Protein Conjugation. Synlett 2017, 28 (15), 1934–1938. https://doi.org/10.1055/s-0036-1590974.[6] Hermanson, G. T. Chapter 6, op. cit., page 304.
 
MAL-dPEG®₈-TFP ester

MAL-dPEG®₈-TFP ester

TFP_Esters_Art2MAL-dPEG®8-TFP ester, product number 10552, is a crosslinking reagent that joins a sulfhydryl to a free amine. The sulfhydryl groups react with a maleimide group via a Michael addition reaction. The amines form amide bonds with the crosslinker by nucleophilic substitution of the 2,3,5,6-tetrafluorophenyl (TFP) ester of the terminal propionic acid group. The maleimide and TFP functional groups on the crosslinking compound sit at either end of a medium-length, discrete polyethylene glycol (dPEG®) chain. The single molecular weight dPEG® spacer is 38 atoms (37.9 Å) long.
Crosslinking ReactionsOne of the most popular, most useful crosslinking reactions in bioconjugate chemistry[1],[2] is the conjugation of free amines to free thiols. These reactions require heterobifunctional reagents that bridge the two groups. Typical crosslinkers are hydrophobic. Quanta BioDesign's dPEG® crosslinking products are water-soluble, amphiphilic, single molecular weight PEG compounds with discrete chain lengths.With conventional hydrophobic crosslinking reagents, aggregation and precipitation of the conjugates occur frequently. These problems do not happen with our water-soluble, non-immunogenic dPEG® crosslinkers. For more information about our dPEG® products, please see our "What is dPEG®?" page. Also, please click here for answers to our most frequently asked questions.TFP Esters are Superior to NHS estersTFP esters are more stable in aqueous buffers than N-hydroxysuccinimidyl (NHS) esters. Moreover, TFP esters have higher reactivity with free amines than NHS esters.[3] NHS esters hydrolyze readily in water or aqueous buffer. As the pH increases, the hydrolysis rate of the NHS ester increases.[4] In 2017, a study by J. Wang, et al., on the performance of fluorophenyl esters concluded, "With regards to PEGylation, the TFP ester performed better than NHS ester."[5] In-house research at Quanta BioDesign confirms the superior performance of TFP esters over NHS esters.How to Use MAL-dPEG®8-TFP esterTFP esters react under the same conditions as NHS esters. However, the optimal pH range for TFP esters (7.5 – 8.0) is slightly higher than for NHS esters (7.0 – 7.5).5 Amide bond formation between the TFP-activated propionic acid group of MAL-dPEG®8-TFP ester and a free amine will be slightly slower at a suboptimal pH compared to the reaction rate within the optimum pH range. Nevertheless, the reaction rate remains relatively rapid.The reaction of the maleimide end of MAL-dPEG®8-TFP ester, product number 10552, with a sulfhydryl proceeds best at pH 6.5 – 7.5. Conduct the conjugation at the lowest reasonable pH within this range. Above pH 7.5, free amines compete with free thiols at the maleimide reaction site, which can cause confusing results. Moreover, at higher pH values, the maleimide ring may open to form unreactive maleamic acid.[6] For details about maleimide-thiol reaction chemistry, please click here.Uses of MAL-dPEG®8-TFP esterMAL-dPEG®8-TFP ester, product number 10552, can be used the same way and in the same applications as the equivalent NHS esters. A 2019 study used PN10552 from Quanta BioDesign to synthesize pyrrolobenzodiazepine dimer antibody-drug conjugates with dual β-glucuronide and dipeptide triggers.[7] Other possible uses for this product include the following:
  • Coating nanoparticle surfaces;
  • Tethering antibodies to atomic force microscopy (AFM) probes;
  • Increasing the water solubility and hydrodynamic volume of hydrophobic biomolecules;
  • Building supramolecular constructs; and,
  • Conjugating the TFP ester end of the molecule a liposomal surface and then using the free maleimide end of the molecule to attach a small molecule drug, peptide, or antibody for targeted delivery of a diagnostic or therapeutic package.
How will you use this product?Bulk Scale Synthesis of MAL-dPEG®8-TFP ester is AvailableIf you need bulk product in a larger package size than our standard sizes, please contact us for a quote. Our commercial capabilities permit us to manufacture this product at any scale that you need.Buy Now!Hydrophobic crosslinkers create more problems than they solve. Traditional disperse polymer PEG crosslinkers add unnecessary analytical complexity to conjugates that incorporate them.So, stop using inferior products!Start using single molecular weight dPEG® crosslinkers and discover the dPEG® difference. To get started, please click the "Add to Cart" button now to order MAL-dPEG®8-TFP ester, product number 10552.Application References:[1] Hermanson, G. T. Chapter 6, Heterobifunctional Crosslinkers. In Bioconjugate Techniques, 3rd ed.; Academic Press: New York, NY, 2013; pp 299–340, specifically page 300. Many scientists engaged in bioconjugation work consider Greg Hermanson's book to be the definitive reference on the subject. Click here now to read a review of Greg's book and to purchase it.[2] Hermanson, G. T. Chapter 18, PEGylation and Synthetic Polymer Modification. In Bioconjugate Techniques, 3rd ed.; Academic Press: New York, NY, 2013; pp 787–838, specifically page 794.[3] Hermanson, G. T. Chapter 3, The Reactions of Bioconjugation. In Bioconjugate Techniques; Academic Press: New York, NY, 2013; pp 229–258, specifically page 239.[4] Ibid, page 234.[5] Wang, J.; Zhang, R.-Y.; Wang, Y.-C.; Chen, X.-Z.; Yin, X.-G.; Du, J.-J.; Lei, Z.; Xin, L.-M.; Gao, X.-F.; Liu, Z.; et al. Polyfluorophenyl Ester-Terminated Homobifunctional Cross-Linkers for Protein Conjugation. Synlett 2017, 28 (15), 1934–1938. https://doi.org/10.1055/s-0036-1590974.[6] Hermanson, G. T. Chapter 6, op. cit., page 304.[7] Gregson, S. J.; Barrett, A. M.; Patel, N. V.; Kang, G.-D.; Schiavone, D.; Sult, E.; Barry, C. S.; Vijayakrishnan, B.; Adams, L. R.; Masterson, L. A.; et al. Synthesis and Evaluation of Pyrrolobenzodiazepine Dimer Antibody-Drug Conjugates with Dual β-Glucuronide and Dipeptide Triggers. European Journal of Medicinal Chemistry 2019, 179, 591–607. https://doi.org/10.1016/j.ejmech.2019.06.044.
 
MAL-dPEG®₄-Tris(-TFP ester)₃

MAL-dPEG®₄-Tris(-TFP ester)₃

MAL-dPEG®4-Tris(TFP ester)3, product number 11416, is a unique crosslinking, monodisperse PEGylation reagent from Quanta BioDesign. This single molecular weight, discrete-length PEG (dPEG®) product permits one-to-three crosslinking of thiol and amine groups. The single maleimido group on one end of the dPEG® linker reacts with free thiols. On the opposite end of the molecule, a tris-based branching structure that terminates with propionic acid groups permits crosslinking with three different amino groups. The crosslinker length from the maleimido olefin to the terminal carbonyl carbon adjacent to the 2,3,5,6-tetrafluorophenyl (TFP) ester is 29 atoms (24.7 Å, avg.) long.
What are the uses of MAL-dPEG®4-Tris(TFP ester)3?The well-known thiol-maleimide reaction permits conjugation of the maleimide group to free thiols. Because cysteine residues are comparatively rare in proteins, the thiol-maleimide reaction gives the user more control over the site(s) of conjugation. Scientists often make use of this reaction in the construction of antibody-drug conjugates (ADCs). The thiol-maleimide reaction is specific for free thiols at pH 6.5 – 7.5. However, specificity disappears above pH 7.5, as the maleimido group reacts with free amines such as the primary amine on the side chain of lysine. To learn more about the thiol-maleimide reaction, please visit our Maleimide Reaction Chemistry page.The TFP ester reacts with free amines similarly to the more well-known N-hydroxysuccinimide (NHS) esters. Research, though, shows that TFP esters are more hydrolytically stable and reactive than NHS esters in aqueous media. Thus, TFP esters are a superior alternative to NHS esters. For more information on TFP esters, please click here.The potential applications of MAL-dPEG®4-Tris(TFP ester)3 are limitless. Some possible uses for this product include the following:
  • Construction of dendrimers and other supramolecular constructs;
  • Creation of ADCs;
  • Modification of hydrogels with surface-accessible sulfhydryl groups; and,
  • Crosslinking small biomolecules such as peptides to create a targeted delivery vehicle.
Learn more about Quanta BioDesign's dPEG® Technology!What is dPEG®?Frequently Asked Questions (about dPEG® products)Is MAL-dPEG®4-Tris(TFP ester)3 Available in Bulk Quantities?Yes, it is. If you need bulk product in a larger package size than our standard sizes, please contact us for a quote. Our commercial capabilities permit us to manufacture this product at any scale that you need.Buy It Now!This unique crosslinking PEGylation reagent from Quanta BioDesign offers all the benefits of traditional PEG products without the analytical complexity caused by dispersity. Our products have no dispersity. Each dPEG® product has a single molecular weight, discrete chain length PEG.To get started, please click the "Add to Cart" button now.
MAL-dPEG®₄-Glu(TFP ester)-NH-m-dPEG®₂₄

MAL-dPEG®₄-Glu(TFP ester)-NH-m-dPEG®₂₄

Click this button to learn more about our Sidewinder™ line of products.MAL-dPEG®4-Glu(TFP ester)-NH-m-dPEG®24, product number 11581, is one of Quanta BioDesign's novel, patent-pending Sidewinder™ line of products. A terminal maleimide group provides thiol-specific reactivity on one end of the molecule, while a long, methyl-terminated dPEG® spacer provides hydrophilicity and protection from proteolysis on the other end of the molecule. Between the two ends, tetrafluorophenyl ester-functionalized glutamic acid offers a convenient attachment point for a hydrophobic drug or other small molecules.
What is dPEG®?The dPEG® tradename describes Quanta BioDesign's patented brand of monodispersed PEGylation reagents. Quanta BioDesign's dPEG® products are high-purity, single molecular weight PEG products with discrete chain lengths. (The "d" in the dPEG® name stands for "discrete.") Our products have no dispersity (Ð = 1), unlike traditional PEG products, which are dispersed polymers.Furthermore, we do not purify our products from a polymeric mixture. Instead, we synthesize dPEG® products from very high-purity starting materials using the traditional tools of synthetic organic chemistry. The result is a well-defined, monodisperse PEG product with high purity and superior performance to a dispersed PEG product. At Quanta BioDesign, we call this "the dPEG® difference."Learn more!What is dPEG®?Frequently Asked Questions (about dPEG® products)What is a Sidewinder™ product?The Sidewinder™ line of products is a novel, patent-pending product line that permits attachment of a hydrophobic drug or other small molecules on the sidearm of an amino acid with dPEG® linkers on either side of the amino acid imparting hydrophilicity, increasing hydrodynamic volume, and protecting from proteolysis. This unique line of products allows users to optimize biodistribution, modulate cell trafficking and internalization, extend serum half-life, and reduce or eliminate immunogenicity.All Sidewinder™ products consist of a functional group for attachment, a short hydrophilic spacer, an amino acid attachment point for functional groups such as small molecule drugs, and a long hydrophilic, non-immunogenic spacer that protects the functional group on the amino acid's sidearm. One typical use for a Sidewinder™ product is creating antibody-drug conjugates (ADCs) with a high drug-antibody ratio (DAR).Importantly, Sidewinder™ products have nearly infinite variability. The spacer length between the terminal reactive group and the amino acid can be as long or short as desired. The amino acid can be varied to include any functionality desired on the sidearm. The terminal protective dPEG® moiety varies in both length and terminal functionality. Also, Sidewinder™ arms can contain multiple amino acids with different functional groups on the sidearms, allowing for highly complex supramolecular constructs.For more information about our Sidewinder™ products, please see Sidewinder™ dPEG® Constructs. To learn more about our dPEG® products, please click the following links:What is dPEG®?Frequently Asked Questions (about dPEG® products)Bulk Quantities Are AvailableIf you need bulk product in a larger package size than our standard sizes, please contact us for a quote. Our commercial capabilities permit us to manufacture this product at any scale that you need.Buy It Now!To get started with your purchase of MAL-dPEG®4-Glu(TFP ester)-NH-m-dPEG®24, product number 11581, please click the "Add to Cart" button now.
MAL-dPEG®₂-TFP ester

MAL-dPEG®₂-TFP ester

TFP_Esters_Art2MAL-dPEG®2-TFP ester, product number 10549, is a crosslinking reagent that joins free amines to free thiols (sulfhydryl groups). The sulfhydryl groups react with a maleimido group via a Michael addition reaction. The amines form amide bonds with the crosslinker by nucleophilic substitution of the 2,3,5,6-tetrafluorophenyl (TFP) ester of the terminal propionic acid group. The maleimido and TFP functional groups on the crosslinking compound sit at either end of a short, discrete polyethylene glycol (dPEG®) chain. The single molecular weight dPEG® spacer is 16 atoms (17.3 Å) long.

Crosslinking Reactions

One of the most popular, most useful crosslinking reactions in bioconjugate chemistry[1],[2] is the conjugation of free amines to free thiols. These reactions require heterobifunctional reagents that bridge the two groups. Typical crosslinkers are hydrophobic. Quanta BioDesign's dPEG® crosslinking products are water-soluble, amphiphilic, single molecular weight PEG compounds with discrete chain lengths.With conventional hydrophobic crosslinking reagents, aggregation and precipitation of the conjugates occur frequently. These problems do not happen with our water-soluble, non-immunogenic dPEG® crosslinkers. For more information about our dPEG® products, please see our "What is dPEG®?" page. Also, click here for answers to our most frequently asked questions.

TFP Esters are Superior to NHS esters

TFP esters are more stable in aqueous buffers than N-hydroxysuccinimidyl (NHS) esters. Moreover, TFP esters have higher reactivity with free amines than NHS esters.[3] NHS esters hydrolyze readily in water or aqueous buffer. As the pH increases, the hydrolysis rate of the NHS ester increases.[4] In 2017, a study by J. Wang, et al., on the performance of fluorophenyl esters concluded, "With regards to PEGylation, the TFP ester performed better than NHS ester."[5] These superior characteristics of TFP esters have been confirmed by in-house research at Quanta BioDesign.

How to Use MAL-dPEG®2-TFP ester

TFP esters react under the same conditions as NHS esters. However, the optimal pH range for TFP esters (7.5 – 8.0) is slightly higher than for NHS esters (7.0 – 7.5).5 Amide bond formation between the TFP-activated propionic acid group of MAL-dPEG®2-TFP ester and a free amine will be slightly slower at a suboptimal pH compared to the reaction rate within the optimum pH range.The maleimide end of MAL-dPEG®2-TFP ester, product number 10549, reacts optimally with a sulfhydryl at pH 6.5 – 7.5. Conduct the conjugation at the lowest reasonable pH within this range. Above pH 7.5, free amines compete with free thiols at the maleimide reaction site, which may confound the data. Moreover, at higher pH values, the maleimide ring may open to form unreactive maleamic acid.[6] For details about maleimide-thiol reaction chemistry, please click here.Uses of MAL-dPEG®2-TFP esterMAL-dPEG®2-TFP ester, product number 10549, can be used the same way and in the same applications as the equivalent NHS esters. Possible uses for this product include the following:
  • Coating nanoparticle surfaces;
  • Tethering antibodies to atomic force microscopy (AFM) probes;
  • Constructing antibody-drug conjugates (ADCs);
  • Adding flexibility and water solubility to a peptide;
  • Increasing the water solubility and hydrodynamic volume of hydrophobic biomolecules;
  • Building supramolecular constructs; and,
  • Conjugating the TFP ester end of the molecule a liposomal surface and then using the free maleimide end of the molecule to attach a small molecule drug, peptide, or antibody for targeted delivery of a diagnostic or therapeutic package.
How will you use this product?

Bulk Scale Synthesis of MAL-dPEG®2-TFP ester is Available

If you need bulk product in a larger package size than our standard sizes, please contact us for a quote. Our commercial capabilities permit us to manufacture this product at any scale that you need.Buy Now!Hydrophobic crosslinkers create more problems than they solve. Traditional disperse polymer PEG crosslinkers add unnecessary analytical complexity to conjugates that incorporate them.So, stop using inferior products!Start using single molecular weight dPEG® crosslinkers and discover the dPEG® difference. To get started, please click the "Add to Cart" button now to order MAL-dPEG®2-TFP ester, product number 10549.Application References:[1] Hermanson, G. T. Chapter 6, Heterobifunctional Crosslinkers. In Bioconjugate Techniques, 3rd ed.; Academic Press: New York, NY, 2013; pp 299–340, specifically page 300. Many scientists engaged in bioconjugation work consider Greg Hermanson's book to be the definitive reference on the subject. Click here now to read a review of Greg's book and to purchase it.[2] Hermanson, G. T. Chapter 18, PEGylation and Synthetic Polymer Modification. In Bioconjugate Techniques, 3rd ed.; Academic Press: New York, NY, 2013; pp 787–838, specifically page 794.[3] Hermanson, G. T. Chapter 3, The Reactions of Bioconjugation. In Bioconjugate Techniques; Academic Press: New York, NY, 2013; pp 229–258, specifically page 239.[4] Ibid, page 234.[5] Wang, J.; Zhang, R.-Y.; Wang, Y.-C.; Chen, X.-Z.; Yin, X.-G.; Du, J.-J.; Lei, Z.; Xin, L.-M.; Gao, X.-F.; Liu, Z.; et al. Polyfluorophenyl Ester-Terminated Homobifunctional Cross-Linkers for Protein Conjugation. Synlett 2017, 28 (15), 1934–1938. https://doi.org/10.1055/s-0036-1590974.[6] Hermanson, G. T. Chapter 6, op. cit., page 304.
 
MAL-dPEG®₁₂-TFP ester

MAL-dPEG®₁₂-TFP ester

TFP_Esters_Art2MAL-dPEG®12-TFP ester, product number 10553, is a crosslinking reagent that joins a sulfhydryl to a free amine. The sulfhydryl groups react with a maleimide group via a Michael addition reaction. The amines form amide bonds with the crosslinker by nucleophilic substitution of the 2,3,5,6-tetrafluorophenyl (TFP) ester of the terminal propionic acid group. The maleimide and TFP functional groups on the crosslinking compound sit at either end of a medium-length, discrete polyethylene glycol (dPEG®) chain. The single molecular weight dPEG® spacer is 49 atoms (51.1 Å) long.
Crosslinking ReactionsOne of the most popular, most useful crosslinking reactions in bioconjugate chemistry[1],[2] is the conjugation of free amines to free thiols. These reactions require heterobifunctional reagents that bridge the two groups. Typical crosslinkers are hydrophobic. Quanta BioDesign's dPEG® crosslinking products are water-soluble, amphiphilic, single molecular weight PEG compounds with discrete chain lengths.With conventional hydrophobic crosslinking reagents, aggregation and precipitation of the conjugates occur frequently. These problems do not happen with our water-soluble, non-immunogenic dPEG® crosslinkers. For more information about our dPEG® products, please see our "What is dPEG®?" page. Also, click here for answers to our most frequently asked questions.TFP Esters are Superior to NHS estersTFP esters are more stable in aqueous buffers than N-hydroxysuccinimidyl (NHS) esters. Moreover, TFP esters have higher reactivity with free amines than NHS esters.[3] NHS esters hydrolyze readily in water or aqueous buffer. As the pH increases, the hydrolysis rate of the NHS ester increases.[4] In 2017, a study by J. Wang, et al., on the performance of fluorophenyl esters concluded, "With regards to PEGylation, the TFP ester performed better than NHS ester."[5] These superior characteristics of TFP esters have been confirmed by in-house research at Quanta BioDesign.How to Use MAL-dPEG®12-TFP esterTFP esters react under the same conditions as NHS esters. However, the optimal pH range for TFP esters (7.5 – 8.0) is slightly higher than for NHS esters (7.0 – 7.5).5 Amide bond formation between the TFP-activated propionic acid group of MAL-dPEG®12-TFP ester and a free amine will be slightly slower at a sub-optimal pH compared to the reaction rate within the optimum pH range.The reaction of the maleimide end of MAL-dPEG®12-TFP ester, product number 10553, with a sulfhydryl proceeds best at pH 6.5 – 7.5. Conduct the conjugation at the lowest reasonable pH within this range. Above pH 7.5, free amines compete with free thiols at the maleimide reaction site, which can cause confusing results. Moreover, at higher pH values, the maleimide ring may open to form unreactive maleamic acid.[6] For details about maleimide-thiol reaction chemistry, please click here.Uses of MAL-dPEG®12-TFP esterMAL-dPEG®12-TFP ester, product number 10553, can be used the same way and in the same applications as the equivalent NHS esters. A 2019 study used PN10553 from Quanta BioDesign to synthesize pyrrolobenzodiazepine dimer antibody-drug conjugates with dual β-glucuronide and dipeptide triggers.[7] Other possible uses for this product include the following:
  • Coating nanoparticle surfaces;
  • Tethering antibodies to atomic force microscopy (AFM) probes;
  • Increasing the water solubility and hydrodynamic volume of hydrophobic biomolecules;
  • Building supramolecular constructs; and,
  • Conjugating the TFP ester end of the molecule a liposomal surface and then using the free maleimide end of the molecule to attach a small molecule drug, peptide, or antibody for targeted delivery of a diagnostic or therapeutic package.
How will you use this product?Bulk Scale Synthesis of MAL-dPEG®12-TFP ester is AvailableIf you need bulk product in a larger package size than our standard sizes, please contact us for a quote. Our commercial capabilities permit us to manufacture this product at any scale that you need.Buy Now!Hydrophobic crosslinkers create more problems than they solve. Traditional disperse polymer PEG crosslinkers add unnecessary analytical complexity to conjugates that incorporate them.So, stop using inferior products!Start using single molecular weight dPEG® crosslinkers and discover the dPEG® difference. To get started, please click the "Add to Cart" button now to order MAL-dPEG®12-TFP ester, product number 10553.Application References:[1] Hermanson, G. T. Chapter 6, Heterobifunctional Crosslinkers. In Bioconjugate Techniques, 3rd ed.; Academic Press: New York, NY, 2013; pp 299–340, specifically page 300. Many scientists engaged in bioconjugation work consider Greg Hermanson's book to be the definitive reference on the subject. Click here now to read a review of Greg's book and to purchase it.[2] Hermanson, G. T. Chapter 18, PEGylation and Synthetic Polymer Modification. In Bioconjugate Techniques, 3rd ed.; Academic Press: New York, NY, 2013; pp 787–838, specifically page 794.[3] Hermanson, G. T. Chapter 3, The Reactions of Bioconjugation. In Bioconjugate Techniques; Academic Press: New York, NY, 2013; pp 229–258, specifically page 239.[4] Ibid, page 234.[5] Wang, J.; Zhang, R.-Y.; Wang, Y.-C.; Chen, X.-Z.; Yin, X.-G.; Du, J.-J.; Lei, Z.; Xin, L.-M.; Gao, X.-F.; Liu, Z.; et al. Polyfluorophenyl Ester-Terminated Homobifunctional Cross-Linkers for Protein Conjugation. Synlett 2017, 28 (15), 1934–1938. https://doi.org/10.1055/s-0036-1590974.[6] Hermanson, G. T. Chapter 6, op. cit., page 304.[7] Gregson, S. J.; Barrett, A. M.; Patel, N. V.; Kang, G.-D.; Schiavone, D.; Sult, E.; Barry, C. S.; Vijayakrishnan, B.; Adams, L. R.; Masterson, L. A.; et al. Synthesis and Evaluation of Pyrrolobenzodiazepine Dimer Antibody-Drug Conjugates with Dual β-Glucuronide and Dipeptide Triggers. European Journal of Medicinal Chemistry 2019, 179, 591–607. https://doi.org/10.1016/j.ejmech.2019.06.044.
MAL-dPEG®₂₄-TFP ester

MAL-dPEG®₂₄-TFP ester

TFP_Esters_Art2MAL-dPEG®24-TFP ester, product number 10554, is a crosslinking reagent with a polyethylene glycol (PEG) cross-bridge that joins free amines to free thiols (sulfhydryl groups). The sulfhydryl groups react with a maleimido group via a Michael addition reaction. The amines form amide bonds with the crosslinker by nucleophilic substitution of the 2,3,5,6-tetrafluorophenyl (TFP) ester of the terminal propionic acid group. The maleimido and TFP functional groups on the crosslinking compound sit at either end of a long, discrete-length chain of PEG (hence, dPEG®). The monodisperse, single molecular weight dPEG® spacer is 87 atoms (92.6 Å) long.
Crosslinking ReactionsOne of the most popular, most useful crosslinking reactions in bioconjugate chemistry[1],[2] is the conjugation of free amines to free thiols. These reactions require heterobifunctional reagents that bridge the two groups. Typical crosslinkers are hydrophobic. Quanta BioDesign's dPEG® crosslinking products are water-soluble, amphiphilic, single molecular weight PEG compounds with discrete chain lengths.Conventional hydrophobic crosslinking reagents frequently trigger aggregation and precipitation of the conjugates made from them. These problems do not happen with our water-soluble, non-immunogenic dPEG® crosslinkers.Traditional PEGylation reagents are made from dispersed polymers. These polymeric reagents are intractably complex. This complexity creates difficulties in the analysis of conjugates. Quanta BioDesign's dPEG® products have no dispersity (Ð = 1). Each dPEG® product consists of a discrete chain of PEG with a single molecular weight. The uniform nature of our dPEG® products eliminates one of the most vexing analytical difficulties faced by users of traditional polymer PEG products.Nevertheless, our customers enjoy all the benefits of PEG, minus the headaches that PEG polymers cause. For more information about our dPEG® products, please see our "What is dPEG®?" page. Also, click here for answers to our most frequently asked questions.TFP Esters are Superior to NHS estersTFP esters are more stable in aqueous buffers than N-hydroxysuccinimidyl (NHS) esters. Moreover, TFP esters have higher reactivity with free amines than NHS esters.[3] NHS esters hydrolyze readily in water or aqueous buffer. As the pH increases, the hydrolysis rate of the NHS ester increases.[4] In 2017, a study by J. Wang, et al., on the performance of fluorophenyl esters concluded, "With regards to PEGylation, the TFP ester performed better than NHS ester."[5] In-house research at Quanta BioDesign confirms the superior performance of TFP esters over NHS esters.How to Use MAL-dPEG®24-TFP esterTFP esters react under the same conditions as NHS esters. However, the optimal pH range for TFP esters (7.5 – 8.0) is slightly higher than for NHS esters (7.0 – 7.5).5 Amide bond formation between the TFP-activated propionic acid group of MAL-dPEG®24-TFP ester and a free amine will be slightly slower at a suboptimal pH compared to the reaction rate within the optimum pH range.The maleimide end of MAL-dPEG®24-TFP ester, product number 10554, reacts optimally with a sulfhydryl at pH 6.5 – 7.5. Conduct the conjugation at the lowest reasonable pH within this range. Above pH 7.5, free amines compete with free thiols at the maleimide reaction site, which may confound the data. Moreover, at higher pH values, the maleimide ring may open to form unreactive maleamic acid.[6] For details about maleimide-thiol reaction chemistry, please click here.Uses of MAL-dPEG®24-TFP esterMAL-dPEG®24-TFP ester, product number 10554, can be used the same way and in the same applications as the equivalent NHS esters. Possible uses for this product include the following:
  • Coating nanoparticle surfaces;
  • Tethering antibodies to atomic force microscopy (AFM) probes;
  • Constructing antibody-drug conjugates (ADCs);
  • Adding flexibility and water solubility to a peptide;
  • Increasing the water solubility and hydrodynamic volume of hydrophobic biomolecules;
  • Building supramolecular constructs; and,
  • Conjugating the TFP ester end of the molecule to a liposomal surface and then using the free maleimide end of the molecule to attach a small molecule drug, peptide, or antibody for targeted delivery of a diagnostic or therapeutic package.
How can you use this product in your next product development project?Bulk Scale Synthesis of MAL-dPEG®24-TFP ester is AvailableIf you need bulk product in a larger package size than our standard sizes, please contact us for a quote. Our commercial capabilities permit us to manufacture this product at any scale that you need.Buy Now!Hydrophobic crosslinkers create more problems than they solve. Traditional disperse polymer PEG crosslinkers add unnecessary analytical complexity to conjugates that incorporate them.So, stop using inferior products!Start using single molecular weight dPEG® crosslinkers and discover the dPEG® difference. To get started, please click the "Add to Cart" button now to order MAL-dPEG®24-TFP ester, product number 10554.Application References:[1] Hermanson, G. T. Chapter 6, Heterobifunctional Crosslinkers. In Bioconjugate Techniques, 3rd ed.; Academic Press: New York, NY, 2013; pp 299–340, specifically page 300. Many scientists engaged in bioconjugation work consider Greg Hermanson's book to be the definitive reference on the subject. Click here now to read a review of Greg's book and to purchase it.[2] Hermanson, G. T. Chapter 18, PEGylation and Synthetic Polymer Modification. In Bioconjugate Techniques, 3rd ed.; Academic Press: New York, NY, 2013; pp 787–838, specifically page 794.[3] Hermanson, G. T. Chapter 3, The Reactions of Bioconjugation. In Bioconjugate Techniques; Academic Press: New York, NY, 2013; pp 229–258, specifically page 239.[4] Ibid, page 234.[5] Wang, J.; Zhang, R.-Y.; Wang, Y.-C.; Chen, X.-Z.; Yin, X.-G.; Du, J.-J.; Lei, Z.; Xin, L.-M.; Gao, X.-F.; Liu, Z.; et al. Polyfluorophenyl Ester-Terminated Homobifunctional Cross-Linkers for Protein Conjugation. Synlett 2017, 28 (15), 1934–1938. https://doi.org/10.1055/s-0036-1590974.[6] Hermanson, G. T. Chapter 6, op. cit., page 304.
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