title: Preparation and characterization of paclitaxel-loaded poly lactic acid-co-glycolic acid coating tracheal stent.
abstract: BACKGROUND
  In-stent restenosis caused by airway granulation poses a challenge due to the high incidence of recurrence after treatment. Weekly applications of anti-proliferative drugs have potential value in delaying the recurrence of airway obstruction. However, it is not practical to subject patients to repeated bronchoscopy and topical drug applications. We fabricated novel pacilitaxel-eluting tracheal stents with sustained and slow pacilitaxel release, which could inhibit the formation of granulation tissue. And we assessed the quality and drug release behaviors of drug-eluting stents (DESs) in vitro.
  
  
  METHODS
  Stents were dipped vertically into a coating solution prepared by dissolving 0.5 g (2% w/v) of poly lactic acid-coglycolic acid (PLGA) and 0.025 g (0.1% w/v) of pacilitaxel in 25 ml of dichloromethane. DES morphology was examined by scanning electron microscopy (SEM). Pacilitaxel release kinetics from these DESs was investigated in vitro by shaking in PBS buffer followed by high performance liquid chromatography (HPLC).
  
  
  RESULTS
  Using an orthogonal experimental design, we fabricated numerous pacilitaxel/PLGA eluting tracheal stents to assess optimum coating proportions. The optimum coating proportion was 0.1% (w/v) pacilitaxel and 2% (w/v) PLGA, which resulted in total pacilitaxel loading of (16.380 6 ± 0.002 1) mg/stent. By SEM the coating was very smooth and uniform. Pacilitaxel released from DES was at (0.376 3 ± 0.003 8) mg/d, which is a therapeutic level. There was a prolonged, sustained release of pacilitaxel of >40 days.
  
  
  CONCLUSIONS
  Paclitaxel-loaded PLGA coating tracheal stents were successfully developed and evaluated. Quality assessments demonstrated favorable surface morphology as well as sustained and effective drug release behavior, which provides an experimental reference for clinical practitioners.
authors.affiliation: Department of Pulmonary Medicine, Beijing Tian Tan Hospital, Capital Medical University, Beijing 100050, China.
authors.forename: Yingying
authors.initials: Y
authors.lastname: Kong
authors.affiliation: Department of Pulmonary Medicine, Beijing Tian Tan Hospital, Capital Medical University, Beijing 100050, China. Email: zhangjie6218@163.com.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Pulmonary Medicine, Beijing Tian Tan Hospital, Capital Medical University, Beijing 100050, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Wang
authors.affiliation: Department of Pulmonary Medicine, Beijing Tian Tan Hospital, Capital Medical University, Beijing 100050, China.
authors.forename: Xiaojian
authors.initials: X
authors.lastname: Qiu
authors.affiliation: Department of Pulmonary Medicine, Beijing Tian Tan Hospital, Capital Medical University, Beijing 100050, China.
authors.forename: Yuling
authors.initials: Y
authors.lastname: Wang
mesh_terms: D054855:Drug-Eluting Stents; D006016:Glycolates / Q000737:chemistry*; D006801:Humans; D019344:Lactic Acid / Q000737:chemistry*; D017239:Paclitaxel / Q000737:chemistry*; D011091:Polyesters; D011108:Polymers / Q000737:chemistry*
chemical_list: D006016:Glycolates; D011091:Polyesters; D011108:Polymers; C031149:glycolic acid; D019344:Lactic Acid; C033616:poly(lactide); D017239:Paclitaxel