Physical properties of zinc, silver, or cerium ion doped borate glass incorporated PCL/gelatin electrospun fibers and their interaction with NG108-15 neural cells

Abstract

In this study, 1393-B3 based borate bioactive glasses (BGs) undoped and doped with 1 wt% zinc (ZnBG), cerium (CeBG), or silver (AgBG) were prepared and were incorporated into gelatin/PCL (GEL/PCL) electrospun fibers for neural tissue engineering applications. Particle sizes of the prepared BGs were 3.1, 10.6, 14.6, and 3.7 µm for undoped BG, ZnBG, AgBG, and CeBG, respectively. Aligned electrospun fibers were prepared with 5 wt% of BG particles to produce 5BG/PCL/GEL, 5ZnBG/PCL/GEL, 5AgBG/PCL/GEL and 5CeBG/PCL/GEL fibers. Random 5CeBG/PCL/GEL fibers were also prepared for comparison. A rise in fiber diameter was measured for BG-incorporated fibers compared to PCL/GEL fibers. Mechanical tests on the fibers indicated ultimate tensile strength values of 1–3.5 MPa, the range of mechanical properties of neural tissue. Cell culture studies were carried out with the NG108-15 cell line. Cell alignment was observed on the electrospun fibers on day 2. On days 1 and 2, the optical density was higher for ZnBG/PCL/GEL, CeBG/PCL/GEL, and AgBG/PCL/GEL than for BG/PCL/GEL fibers. On day 4, undoped BG-containing nanofibers had higher optical density compared to those containing doped BGs. This result could be due to a slower release rate of boron from the pure BG/PCL/GEL fiber mat. Overall, within the studied range, all fiber mats were found to be suitable for neural tissue engineering in terms of neural cell compatibility and mechanical properties. In the future, a wider range of ion doping must be considered to fully comprehend the potential of such ion-releasing fibers for neural regeneration.

Graphical Abstract