Polycaprolactone powder

Polycaprolactone powder (MW 50000 Daltons; Tm = 58°C; PCL) was supplied by Polysciences Inc. The low molecular weight chitosan powder (deacetylation degree ≥ 75%; Tm = 102.5°C; CS) and the 5-Fluorouracil (MW 130.08 g/mol; sparingly soluble in water <1 mg/ml; ≥ 99% HPLC; Tm = 282°C; 5-FU) were purchased from Sigma-Aldrich.

Polycaprolactone powder (PCL, Mw = 50,000 gmol⁻¹) was purchased from Polyscience Europe (Germany). Tetracycline Hydrochloride (TH, Mw = 480.90 gmol⁻¹) was purchased from Sigma Aldrich, USA, and iron oxide nanoparticles (IONP) (Fe₃O₄, particle size < 63 nm) were obtained from Inoxia chemicals (UK).

The pure PCL scaffold was prepared with polycaprolactone powder (Cat# 25090, M_W = 50,000, Polysciences, Warrington, UK) and a 3D-Bioplotter (Envisiontec, 3D-Bioplotter, Gladbeck, Germany). The nozzle size and strand distance of the scaffold were 200 and 300 μm, respectively. The powder was placed in a steel syringe fastened to the printer and dispensed through a steel nozzle at temperatures >100 °C by applying air pressure (600 ± 25 kPa), and the feed rate was set at 80 mm/min. The PCL scaffolds were printed with a 5.0 mm diameter and were 1.0 mm in height. All scaffolds were sterilized with ethylene oxide before use [40 (link)]. Before coating with PRP, the scaffolds were first treated with ethanolic sodium hydroxide and 30% 0.25 M NaOH:70% absolute ethanol for 2 min to improve surface wettability [41 (link)]. Finally, the scaffolds were observed under a scanning electron microscope (SEM, Hitachi, S-450, Tokyo, Japan).