Electrospinning of collagen with nanocapsules of PLGA for delivery of paclitaxel in drug-eluting stents

L.M. Agudelo, J.A.C. Cornelio, L.F. Rodriguez, I.C. Ortiz, L.M. Hoyos, G.J. Colmenares
Universidad Pontificia Bolivariana,

Keywords: electrospinning, collagen, PLGA, nanocapsules, drug-eluting stents


Drug-eluting stents can facilitate a drug’s release directly to the specific site, but the main difficulty with drug-eluting stents is that the initial burst of drug release can extremely affect the pharmacological action and this is the biggest drawback that worries physicians and researchers in this field [1], [2]. Therefore, the drug release rate has become an important standard in evaluating Drug-eluting stents [2]. The factors affecting the drug release rate include the drug, drug carrier, coating methods, drug storage, direction of elution, coating thickness, pore size in the coating, and release conditions like pH, temperature, release medium and hemodynamics after the stent implantation. This work develops a new delivery system trying to understand better, the factors that influences the drug release. This system use nanofiber produced by electrospinning technic and bioabsorbable polymeric nanocapsules produced by the nanoprecipitation processes in a recirculated system develop in the research group. We used the electrospinning processes because is perhaps the most promising of all nanotechnologies, in terms of versatility and cost to produce nanofibers, with large surface area, porosity, orientation, and dimensions, in a controlled manner with excellent mechanical and easy functionalization properties for multiple applications [3]–[8]. For this work, we used an electrospinning equipment built at the university, in which you can control the process parameters such as voltage, deposition rate, collector distance, speed and direction of rotation of the collector, to control the morphology and diameter of the nanofibers. The final electrospinning condition to obtain nanofiber of collagen with a diameter of 100 nm approximately was: a voltage of 18 V, the collector distance was of 14 cm, a flow rate of 0.1mL/h, and the concentration of polymer was 25% W/V in acetic acid and distilled water 1:1. On the other hand, we encapsulated Paclitaxel in bioabsorbable polymeric nanocapsules of PLGA (Resomer 752 H, donated by Evonik) produced in a continuous recirculated system by nanoprecipitation technic, according to previous works [9], [10]. The nanocapsules were lyophilized and added to the collagen solution for electrospinning of the samples. The nanostructured delivery system and his individual components were characterized using TEM, SEM, AFM, contact angle and DLS for the nanocapsules. The released of paclitaxel was measured using the HPLC method