Fabrication of a polymer-based biodegradable stent using a CO2 laser
Wybrane pełne teksty z tego czasopisma
This paper deals with CO2 laser machining of biodegradable polymers. We investigate the influence of laser parameters on the quality and geometry of cuts made in poly(l-lactide) and poly(l-lactide-co-glycolide). Because of the thermal character of material removal, liquid phase occurs and heat propagates into the material, changing its properties near the cutting zone. For this reason, the mechanical properties of laser cut samples were examined. Oar-shaped samples cut with a CO2 laser were compared with injection moulded samples and also with those manufactured using a KrF excimer laser. Samples with dimensions comparable to those of stent struts were examined in a uniaxial quasi-static tensile test. The influence of laser power and scanning speed on the geometry of cuts was investigated. Narrow cuts (120 µm) were made in 250 µm-thick polymer sheets. A tubular stent based on poly(l-lactide) was designed and then fabricated using a CO2 laser. We noted that this method allows achieving stent struts that are 300 µm wide; however, for such narrow elements the influence of the heat-affected zone can be critical. We believe that this technique has a potential to become an alternative, cost-efficient method of manufacturing biodegradable stents.
Bibliogr. 29 poz., rys., tab., wykr.
-  L. Räber, S. Windecker, Current status of drug-eluting stents, Cardiovascular Therapeutics 29 (3) (2011) 176–189.
-  R.C. Eberhart, S.H. Su, K.T. Nguyen, M. Zilberman, L. Tang, K.D. Nelson, P. Frenkel, Bioresorbable polymeric stents: current status and future promise, Biomaterials Science, Polymer Edition 14 (4) (2003) 299–312.
-  R. Waksman, Update on bioabsorbable stents: from bench to clinical, Interventional Cardiology 19 (5) (2006) 414–421.
-  D. Schranz, P. Zartner, I. Michel-Behnke, H. Akintürk, Bioabsorbable metal stents for percutaneous treatment of critical recoarctation of the aorta in a newborn, Catheterization and Cardiovascular Interventions 67 (5) (2006) 671–673.
-  R.S. Stack, R.M. Califf, H.R. Phillips, Interventional cardiac catheterization at Duke Medical Center, American Journal of Cardiology 62 (10 Pt 2) (1988) 3F-24F.
-  H. Tamai, K. Igaki, E. Kyo, Initial and 6-month results of biodegradable poly-l-lactic acid coronary stents in humans, Circulation 102 (2000) 399–404.
-  T. Yamawaki, H. Shimokawa, T. Kozai, Intramural delivery of a specific tyrosine kinase inhibitor with biodegradable stent suppresses the restenotic changes of the coronary artery in pigs in vivo, Journal of the American College of Cardiology 32 (3) (1988) 780–786.
-  P. Erne, M. Schier, T.J. Resink, The road to bioabsorbable stents: reaching clinical reality?, Cardiovascular and Interventional Radiology 29 (1) (2006) 11–16.
-  M. Bartkowiak-Jowsa, R. Będziński, B. Szaraniec, J. Chłopek, Mechanical, biological, and microstructural properties of biodegradable models of polymeric stents made of PLLA and alginate fibers, Acta of Bioengineering and Biomechanics 13 (4) (2011) 21–28.
-  R. Waksman, Current state of the absorbable metallic (magnesium) stent, EuroIntervention 5 (2009) F94–F98.
-  D. Stoeckel, C. Bonsignore, S. Duda, A survey of stent design, Minimally Invasive Therapy & Allied Technologies 11 (4) (2002) 137–147.
-  L.V. Zhigilei, B.J. Garrison, Microscopic mechanisms of laser ablation of organic solids in the thermal and stress confinement irradiation regimes, Applied Physics 88 (3) (2000) 1281–1298.
-  S.D. Gittard, R.J. Narayan, Laser direct writing of micro- and nano-scale medical devices, Expert Review of Medical Devices 7 (3) (2010) 343–356.
-  P.R. Miller, R. Aggarwal, A. Doraiswamy, Laser micromachining for biomedical applications, JOM 61 (9) (2009) 35–40.
-  N.B. Dahotre, S.P. Harimkar, Laser Fabrication and Machining of Materials, Springer, New York, 2008.
-  C. Momma, U. Knop, S. Nolte, Laser cutting of slotted tube coronary stents—state-of-the-art and future developments, Progress in Biomedical Research 4 (1) (1999) 39–44.
-  M. Womack, M. Vendan, P. Molian, Femtosecond pulsed laser ablation and deposition of thin films of polytetra fluoroethylene, Applied Surface Science 221 (1-4) (2004) 99–109.
-  R. Ortiz, I. Quintana, J. Etxarri, Picosecond laser ablation of poly-L-lactide: effect of crystallinity on the material response, Applied Physics 110 (9) (2011) 094902.
-  M. Unverdorben, A. Spielberger, M. Schywalsky, A Polyhydroxybutyrate, Biodegradable stent: preliminary experience in the rabbit, Cardiovascular and Interventional Radiology 25 (2) (2002) 127–132.
-  N. Grabow, C.M. Bünger, C. Schultze, A biodegradable balloon-expandable stent for interventional applications in the peripheral vasculature—in vitro feasibility, IFMBE Proceedings 22 (2009) 2213–2215.
-  N. Grabow, C.M. Bünger, C. Schultze, A biodegradable slotted tube stent based on poly(L-lactide) and poly(4-hydroxybutyrate) for rapid balloon-expansion, Annals of Biomedical Engineering 35 (12) (2007) 2031–2038.
-  M. Bartkowiak-Jowsa, R. Będziński, A. Kozłowska, J. Filipiak, C. Pezowicz, Mechanical, rheological, fatigue, and degradation behavior of PLLA, PGLA and PDGLA as materials for vascular implants, Meccanica 48 (2013) 721–731.
-  C.M.B. Gonçalves, J.A.P. Coutinho, I.M. Marrucho, in: R. Auras, L.T. Lim, S.E.M. Selke, H. Tsuji (Eds.), Poly(Lactic Acid): Synthesis, Structures, Properties, Processing, and Applications, John Wiley & Sons, Inc., Hoboken, 2010, pp. 97–112.
-  R. Auras, B. Harte, S. Selke, An overview of polylactides as packaging materials, Macromolecular Bioscience 4 (9) (2004) 835–864.
-  M.L. Di Lorenzo, Crystallization behavior of poly (L-lacticacid), European Polymer Journal 41 (3) (2005) 569–575.
-  D.K. Gilding, A.M. Reed, Biodegradable polymers for use in surgery—polyglycolic/poly(actic acid) homo-and copolymers: 1, Polymer 20 (12) (1979) 1459–1464.
-  C. Migliaresi, et al., Dynamic mechanical and calorimetric analysis of compression molded PLLA of different molecular weights: effect of thermal treatments, Journal of Applied Polymer Science 43 (1) (1991) 83–95.
-  G. Perego, G.D. Cella, C. Bastioli, Effect of molecular weight and crystallinity on poly(lactic acid) mechanical properties, Journal of Applied Polymer Science 59 (1) (1996) 37–43.
-  L. Fambri, C. Migliaresi, in: R. Auras, L.T. Lim, S.E.M. Selke, H. Tsuji (Eds.), Poly(Lactic Acid): Synthesis, Structures, Properties, Processing, and Applications, John Wiley & Sons, Inc., Hoboken, 2010, pp. 113–124.