PEG-PCL Polycaprolactone

Polycaprolactone (PCL) is a biodegradable polyacid ester. PEG-PCL is a block copolymer of hydrophilic polyethylene glycol and hydrophobic polycaprolactone. This type of amphiphilic polymer is advantageous in increasing the encapsulation of hydrophobic drugs through hydrophobic-hydrophobic interactions or coupling of drugs to PCL. The hydrophilic portion of PEG will increase the solubility of the drug cargo for human use. BOC Sciences offers PEG-PCL copolymers with different PEG and PCL molecular weights for drug discovery studies. In addition, we offer PEG-PCL copolymers modified with acids, amines, maleimides, and N-hydroxysuccinimide groups.

Fig. 1. Formation of PCL-PEG-PCL (Journal of Chemical Education. 2020, 97(11): 4158-4165).

Examples of PEG-PCL

COOH-PEG-PCL

The molecular chain of COOH-PEG-PCL consists of a hydrophilic PEG block and a hydrophobic PCL block. The carboxylic acid functional group at the end of the chain allows for quick and easy surface functionalization to prepare nanoparticles and micelles for targeted drug delivery. COOH-PEG-PCL is one of the most commonly used biodegradable ABC polymers for drug delivery. By varying the molecular weight ratio between hydrophilic and hydrophobic blocks and controlling the formulation parameters, well-defined nanoparticles with tunable size and properties can be prepared.

MAL-PEG-PCL

MAL-PEG-PCL is a functional amphiphilic block copolymer with a molecular chain consisting of a hydrophilic PEG block and a hydrophobic PCL block. The maleimide at the end of the chain can be conjugated with thiol, SH or mercapto groups to form disulfide bonds. Micelles are used for the preparation of nanoparticles and targeted drug delivery. MAL-PEG-PCL is biocompatible and can self-assemble to form nanoparticles in aqueous and non-aqueous media such as micelles and polymersomes.

NH2-PEG-PCL

NH2-PEG-PCL is a functional amphiphilic block copolymer (ABC) with an amine-based hydrophobic block PCL at the end of the molecular chain. It can self-assemble into pH-sensitive polymeric micelles. NH2-PEG-PCL is a biodegradable, biocompatible polyester chain segmented polyethylene glycolized copolymer. PEG blocks with amine groups at the end are used to prepare nanoparticles and micelles for targeted drug delivery. The active group at the end of the product can be attached to a number of modified peptides, proteins, glycans, folic acid or antibodies to give active targeting.

Functions of PEG-PCL

(1) Controlled release systems: PEG-PCL copolymers can be used to prepare controlled release systems for the slow, sustained release of drugs or other biologically active substances.

(2) Degradability: The PCL segment gives the PEG-PCL copolymer degradability, i.e., it can be naturally degraded and metabolized in the body after a certain period of time.

(3) Regulation of physical properties: The physical properties of PEG-PCL copolymers can be regulated by adjusting the length and ratio of PCL and PEG segments. This includes the mechanical properties, surface properties, melting point and glass transition temperature of the copolymer. This flexibility allows the copolymers to be adapted to different application requirements and provide the desired physical properties.

How to Prepare PEG-PCL?

The PEG and PCL monomers are dissolved in a suitable organic solvent to ensure that the monomers are fully dissolved and a homogeneous reaction system is formed. After that, a suitable catalyst is added to the reaction system. Then, the reaction system is placed under appropriate reaction conditions for polymerization. This includes controlling the reaction temperature and reaction time to promote the formation of the polymer. Finally, at the appropriate time point, the polymerization reaction is stopped to terminate the growth of the polymer, after which the final product is purified.

As a trusted supplier of PEG-PCL, BOC Sciences is committed to providing high-quality products to meet the ever-changing needs of researchers and industry professionals.

Reference

1. Wu, K. et al. Synthesis of PCL-PEG-PCL triblock copolymer via organocatalytic Ring-Opening polymerization and its application as an injectable hydrogel-an interdisciplinary learning trial. Journal of Chemical Education. 2020, 97(11): 4158-4165.