ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

PLA/PEG particles in agar hydrogels for injectable drug delivery

Ehsan Zeraatkar and Masoud Frounchi

Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran

E-mail: frounchi@sharif.edu

Received: 24 November 2024  Accepted: 9 April 2025

Abstract:

Particles of biocompatible and biodegradable polylactic acid and polyethylene glycol (PLA/PEG) were prepared and loaded with doxorubicin hydrochloride (DOXH) as a medication for cancer treatment. Hydrogels of a natural polysaccharide, agar, were used as a matrix for distribution of PLA/PEG/DOXH particles that can be injected directly to cancerous site by exploiting the thermo-gelation property of agar. Field emission scanning electron microscopy showed that PLA/PEG particles were almost spherical with a size range of 100 to 350 nm. The average size of particles was 190 nm as measured by dynamic light scattering method. DSC results indicated that PLA and PEG were miscible as judged by a large shift in glass transition temperature of PLA. The miscibility of PLA/PEG reduced drastically the cold crystallization rate of PLA, so the PLA/PEG blend remained essentially amorphous after solvent evaporation. Thus, the drug release rate through plasticized and amorphous PLA matrix was faster than semicrystalline neat PLA. Addition of hydrophilic PEG to hydrophobic PLA improved the encapsulation efficiency of the particles for the hydrophilic DOXH. Embedding the particles within agar hydrogels provided further control on adjusting the drug release rate by varying the agar concentration.

Keywords: Biomedical Materials; Biomaterials; Colloids; Gels and Hydrogels; Nanoparticles; Polyhydroxyalkanoates; PLA/PEG particles; Biocompatible; Agar hydrogels; Drug delivery

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-025-04067-8

Chemical Papers 79 (7) 4449–4457 (2025)