Fabrication of triblock ABA type peptide dendrimer based on glutamic acid dimethyl ester and PEG as a potential nano drug delivery agent

Introduction: Peptide dendrimers build up from amino acids and they simulate to artificial proteins with globular architecture. These characteristics furnish dendrimers with best biodegradability and biocompatibility in drug delivery systems.
Methods: A barbell-like dendrimer from glutamic acid dimethyl ester-poly (ethylene glycol)-glutamic acid dimethyl ester as ABA-type triblock copolymer PG-PEG-PG) was prepared with liquid-phase peptide synthesis via a divergent approach. PEG 600 diacid (PEG-A) and glutamic acid dimethyl ester were as the core and the monomeric building blocks, respectively. Linear-dendritic copolymer was prepared in the presence of DCC in pyridine. Transmission electron microscope (TEM) was used for measuring the size of first generation (G1-COOH) and second generation (G2-COOH) of dendrimer compounds. Thermal behavior of the synthesized dendrimers was investigated using DSC.
Results: The desired generations G1-COOH, G2-COOH and G3-COOH were prepared by divergent method using PEG diacid 600 as a core compound. The size range of the resulted particles was found to be 20-100 nm for various generations. The isolated dendrimer was examined as the drug-delivery agent and the controlled release was carried out for drug molecule in pH 7.4.
Conclusion: Based on the obtained results, the synthesized biocompatible dendrimers could potentially be utilized as a drug carrier agent.