I. Basic Information

Polysarcosine (pSar) is a polyamino acid material prepared by ring-opening polymerization of sarcosine-derived N-carboxy anhydride (Sar-NCA). Its repeating unit contains an N-methylglycine structure, and its backbone is connected by amide bonds. pSar exhibits good hydrophilicity, biocompatibility, and anti-protein adsorption properties.

As an emerging hydrophilic polymer, pSar has attracted increasing attention in the field of biomedical materials and is being investigated as a potential hydrophilic modification material beyond polyethylene glycol (PEG). With its tunable structure, hydrophilicity, anti-protein adsorption properties, and potential biodegradability, pSar is being explored in drug delivery, bioconjugation, and nanomaterial surface functionalization.

II. Structural Features and Mechanism

The pSar backbone is composed of amide bonds, with N-methylated amide structures in its repeating units, contributing to its good hydrophilicity and water solubility.

Compared with conventional PEG, pSar offers the following structural characteristics:

1. High Hydrophilicity and Anti-Protein Adsorption Properties

pSar chains can form a stable hydration layer, reducing nonspecific protein adsorption and improving the biocompatibility of material surfaces. This property makes pSar suitable for surface hydrophilization of nanoparticles and drug delivery systems, and may help improve their stability in biological environments.

2. Tunable Molecular Weight and Chain Length

By adjusting the degree of polymerization, pSar products with different molecular weights can be obtained, such as pSar25, pSar50, and pSar100. These materials provide options for different drug delivery and bioconjugation systems. pSar with different degrees of polymerization can form hydrophilic modification layers with different chain lengths, providing flexibility for regulating material surface properties and biointerface interactions.

3. Terminal Functionalization

Depending on the terminal functional group, pSar can be functionalized with groups such as amino, carboxyl, thiol, azide, and alkyne groups for conjugation with other molecules. This provides a material basis for protein modification, nanomaterial functionalization, and the construction of targeted delivery systems.

4. Potential Biodegradability

The pSar backbone contains amide bonds and may undergo degradation under specific enzymatic conditions. Compared with conventional non-degradable hydrophilic polymers, this characteristic makes pSar a material of interest for further research in biomedical applications.

III. Major Applications

1. Drug Delivery Systems

pSar can be used as a hydrophilic modification segment in drug delivery materials to improve the aqueous dispersibility and stability of drug carriers. In nanomedicine delivery systems, pSar may reduce nonspecific interactions between carriers and plasma proteins and help improve their stability under physiological conditions. pSar has been investigated in polymeric micelles, lipid nanoparticles (LNPs), and protein delivery systems.

2. Protein and Peptide Modification

Similar to PEGylation, pSar can be conjugated to proteins and peptides through terminal functional groups for hydrophilic modification. pSar modification may improve the solubility and stability of certain biomolecules and provides a material basis for research into biomolecule hydrophilization and long-acting delivery systems.

3. Nanomaterial Surface Functionalization

With its hydrophilic and low-protein-adsorption characteristics, pSar can be used for surface modification of gold nanoparticles, polymeric nanoparticles, and other nanomaterials. Constructing a pSar-based surface layer can regulate interactions between nanomaterials and biological systems, supporting research in targeted delivery and biosensing.

4. Biomedical Materials Research

pSar can also be investigated for use in hydrogels, biointerface materials, and other functional polymer systems. Its structurally tunable nature enables further functional modification according to specific application requirements.

IV. Related Products

For more information on Polysarcosine (pSar) products, please visit the Sinopeg product center.