Functional hydrophilic highly biodegradable PCL nanofibers through direct aminolysis of PAMAM dendrimer

Abstract

Polycaprolactone (PCL) was modified with second-generation poly(amidoamine) dendrimer (PAMAM-G2) in electrospinning solution through aminolysis of PCL ester bonds. Two factors affected the modification of PCL in the presence of PAMAM dendrimer. One of them was the concentration of PAMAM, and the other one was the mixing time with PCL. Therefore, PCL/PAMAM nanofiber scaffolds with the ratios of 85:15, 75:25, and 65:35 and mixing times of 1 h and 3 h were fabricated. The presence of NH2 terminal groups of dendrimers and OH groups formed after aminolysis reduced the contact angle from 98° for pure PCL to 9° for a PCL/PAMAM with a ratio of 65:35 mixed for three hours. The degradability test showed that 65:35 specimen lost 47.5% of its initial weight after 8 weeks while for pure PCL was less than 3%. To evaluate the host-guest properties of PCL/PAMAM nanofiber, curcumin was incorporated into the solution before electrospinning as a drug model. MTT assay, cell morphology study and anticancer activity of PCL/PAMAM/curcumin nanofibers against breast cancer cells (MCF-7) showed that by increasing the concentration of dendrimer from 15% to 35%, curcumin loading in the sample increased and inhibition of cancer cells increased from 31.5% to 42.4%, respectively.