1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide, Polymer-Bound: A Key Reagent in Chemical Synthesis

1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide, polymer-bound, often abbreviated as EDC polymer-bound, is a carbodiimide derivative widely used as a coupling reagent in chemical and biochemical synthesis. 3-ethylcarbodiimide is particularly effective in facilitating the formation of amide bonds between carboxylic acids and amines, a reaction commonly encountered in peptide synthesis, bioconjugation, and the modification of biomolecules. When polymer-bound, EDC is immobilized on a solid support, making it easier to remove from reactions and enhancing the efficiency of large-scale applications.

Chemical Structure and Properties

The compound’s structure can be broken down as follows:

• Carbodiimide Group: The carbodiimide functional group (–N=C=N–) is central to EDC’s ability to activate carboxyl groups, which enables them to react with amines.

• 3-Dimethylaminopropyl Group: The 3-dimethylaminopropyl group (-CH₂CH₂N(CH₃)₂) is a stabilizing electron-donating group that enhances the reactivity of the carbodiimide.

• Polymer-Bound Form: EDC polymer-bound involves the attachment of the EDC molecule to a polymer support, such as polystyrene or other resins, through a covalent bond. This form of EDC makes it easier to remove the reagent from the reaction mixture after use, providing advantages in both purification and reuse.

The polymer-bound nature of this carbodiimide derivative allows for greater control over the reaction process, reducing the amount of unreacted reagent in the final product.

Mechanism of Action

The main mechanism of action for 1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide in coupling reactions involves the activation of a carboxyl group. Here’s how it works:

1. Activation of the Carboxyl Group: EDC reacts with the carboxyl group (-COOH) of a carboxylic acid, forming an O-acylisourea intermediate.

   R−COOH+EDC→R−CO−N=C=N−CH2CH2N(CH3)2R-COOH + EDC → R-CO-N=C=N-CH₂CH₂N(CH₃)₂R−COOH+EDC→R−CO−N=C=N−CH2​CH2​N(CH3​)2​

2. Nucleophilic Attack by Amines: The amine then attacks the activated carboxyl group, displacing the EDC-derived group and forming an amide bond. This results in the desired amide linkage between the carboxyl and amine components.

3. Hydrolysis of the Intermediate: The activated O-acylisourea intermediate is susceptible to hydrolysis under aqueous conditions, which can lead to side reactions. However, polymer-bound EDC can be used to reduce these undesired side reactions because the solid support allows for easier removal of excess reagent.

Applications

1. Peptide and Protein Synthesis

One of the most common uses of EDC polymer-bound is in peptide synthesis. The coupling of amino acids to form peptides often requires the activation of carboxyl groups, and EDC provides an efficient means to achieve this. By using the polymer-bound form, researchers can perform multiple coupling reactions without worrying about the removal of excess carbodiimide reagents.

This is especially useful in solid-phase peptide synthesis (SPPS), where the polymer-bound form can be used to selectively couple amino acids to a resin-bound peptide chain, which is then cleaved and purified.

2. Bioconjugation

EDC polymer-bound is also used in bioconjugation applications, where it facilitates the coupling of biomolecules, such as proteins or nucleic acids, to other molecules like fluorescent dyes, biotin, or affinity ligands. These conjugates are valuable in diagnostics, drug delivery systems, and biosensors.

For example, EDC can be used to couple antibodies to enzymes or to conjugate other biomolecules to surfaces in biosensor applications, enabling the detection of specific molecules or pathogens.3-ethylcarbodiimide

3. Carbohydrate Conjugation

EDC is useful for coupling carbohydrates to proteins or other molecules. Carbohydrates often need to be conjugated to proteins to study their biological functions or to develop glycoproteins. EDC polymer-bound simplifies this process by providing a controlled and efficient coupling reaction, reducing the chances of side reactions.3-ethylcarbodiimide

4. Modification of Surfaces and Nanomaterials

Polymer-bound EDC is used in the functionalization of nanomaterials and surfaces. For example, when attaching biomolecules to nanoparticles, EDC can activate the surface-bound carboxyl groups, allowing for the efficient conjugation of amine-terminated molecules to the surface, forming stable surface conjugates.3-ethylcarbodiimide

This is important in areas such as drug delivery, biosensing, and immunoassays, where nanoparticles are functionalized with biomolecules like antibodies, proteins, or enzymes to achieve specific targeting or detection functions.

5. Polymer Chemistry

In polymer chemistry, EDC polymer-bound can be used to introduce functional groups onto the surface of polymers. This functionalization is essential in creating smart polymers with specific properties, such as responsive behavior to external stimuli, or in enhancing polymer compatibility with biological systems.3-ethylcarbodiimide

Advantages of Polymer-Bound EDC

1. Reusability: One of the significant advantages of using polymer-bound EDC is that it can be reused multiple times in reactions, reducing the amount of reagent needed. After the reaction, the polymer-bound EDC can be easily separated from the product and reused, making it cost-effective for large-scale reactions.

2. Reduced Side Reactions: In its polymer-bound form, EDC is more controlled, reducing the chances of side reactions such as hydrolysis of the O-acylisourea intermediate. This improves the yield and purity of the final product.

3. Simplified Workup: Since EDC is immobilized on a solid support, it can be easily removed from the reaction mixture by simple filtration or washing steps, simplifying the workup process and improving the efficiency of the synthesis.

4. Increased Selectivity: The use of polymer-bound EDC can increase the selectivity of the coupling reaction by minimizing the formation of unwanted by-products, which is important in both academic and industrial settings.

Safety and Handling

While 1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide is a relatively safe reagent, it should be handled with care, especially in its free form. It can cause irritation to the skin, eyes, and respiratory system. Always use appropriate personal protective equipment (PPE) such as gloves, goggles, and a lab coat when handling this compound.

In its polymer-bound form, handling risks are minimized as the reagent is immobilized and less likely to cause exposure to workers. However, proper disposal procedures should still be followed, as the polymer-bound EDC may still contain reactive sites.

Conclusion

1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide, polymer-bound, is a highly effective and versatile coupling reagent used in chemical and biochemical synthesis. Its ability to efficiently form amide bonds between carboxylic acids and amines makes it invaluable in peptide synthesis, bioconjugation, and other applications that require controlled and efficient coupling reactions. 3-ethylcarbodiimide polymer-bound form enhances the reagent’s usability by simplifying purification, improving selectivity, and allowing for reusability in large-scale reactions. With its wide range of applications and efficiency, EDC polymer-bound continues to be an essential tool in chemical and biotechnological research and industry.

Phone : +49 1512 4714765 ( Germany )
Phone : +1 (702) 381-3042 ( USA )
Email : [email protected]
Address : Cunostraße 56, 14193 Berlin. Germany
Address : 7373 Rowlett Park Dr, Tampa, FL 33610, United States.