Swelling properties and drug release of new biocompatible POEGOPGMA hydrogels with VPTT near to the human body temperature

Abstract

Oligo (ethylene glycol) oligo (propylene glycol) methacrylates (OEGOPGMA) with diferent numbers of ethylene glycol (EG) and propylene glycol (PG) units in backbone were used for the preparation of new thermoresponsive POEGOPGMA hydrogels; EG6PG3MA and EG3PG6MA monomers were used; and three diferent POEGOPGMA hydrogels (PEG6PG3MA, PEG3PG6MA and P(EG6PG3/EG3PG6) MA copolymer with equal mol% of previous two) were fabricated from mono‑ mer–solvent (OEGOPGMA–water/ethanol) mixture by gamma radiation. Charac‑ terisation of the hydrogels was conducted by swelling, UV–Vis, scanning electron microscope, diferential scanning calorimetry and in vitro biocompatibility (cyto‑ compatibility and haemolytic activity) investigations. The modelling of drug release and difusion characteristics was tested using cephalexin drug. For the frst time, it was shown how to efectively tune the volume phase transition temperature (VPTT) values of the hydrogels by changing the ratio of more hydrophilic (EG) and more hydrophobic (PG) units in (EGPG) “block” pendant chains. The obtained hydrogels revealed the great potential for diferent biomedical applications not only due to the possibility to tune VPTT in the desired way but also due to the good biocompatibil‑ ity and controlled drug delivery within the target temperature range.