title: Experimental studies on soft contact lenses for controlled ocular delivery of pirfinedone: in vitro and in vivo.
abstract: BACKGROUND
  Pirfinedone (PFD) is a novel agent which has the potential to prevent scarring in the eyes. The 0.5% PFD eye drops exhibits poor bioavailability. Whereas, the feasibility of using contact lens as ocular drug delivery device initiated novel possibilities.
  
  
  OBJECTIVE
  To evaluate the delivery of PFD by soft contact lens (SCL) in vivo, we screened the most suitable lens material for PFD among various commercially available SCL materials in vitro.
  
  
  METHODS
  Firstly, 11 different SCLs (-1.00 diopter) were respectively soaked in 2 ml of 0.05% PFD-loading solution for 24 h to fully absorb drug, and then placed in fresh phosphate buffered saline (PBS) to release the drug. PFD concentration in PBS was determined by ultraviolet absorbance at 310 nm. Secondly, by immersing in 2 ml of 0.5% PFD eye drops for 24 h, the polymacon lens (0.00 diopter) was then placed on the cornea of New Zealand rabbits. PFD concentrations were detected by high performance liquid chromatography (HPLC) in tears, aqueous humor, conjunctiva, cornea, and sclera at different time points.
  
  
  RESULTS
  PFD showed some affinity for pHEMA-based lenses and the polymacon lens more slowly released more amount of PFD than any other lens in vitro (p < 0.001). Compared with eye drops, drug-loaded SCLs greatly enhanced the retention time and concentrations of PFD in cornea and aqueous humor and consequently improved the bioavailability of PFD.
  
  
  CONCLUSIONS
  Polymacon-based SCL is probably a promising vehicle to be an effective ophthalmic delivery system for PFD.
authors.affiliation: a State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University , Guangzhou , China , and.
authors.forename: Mei
authors.initials: M
authors.lastname: Yang
authors.affiliation: a State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University , Guangzhou , China , and.
authors.forename: Yangfan
authors.initials: Y
authors.lastname: Yang
authors.affiliation: b School of Pharmaceutical Sciences, Sun Yat-Sen University , Guangzhou , China.
authors.forename: Ming
authors.initials: M
authors.lastname: Lei
authors.affiliation: a State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University , Guangzhou , China , and.
authors.forename: Chengtian
authors.initials: C
authors.lastname: Ye
authors.affiliation: b School of Pharmaceutical Sciences, Sun Yat-Sen University , Guangzhou , China.
authors.forename: Chunshun
authors.initials: C
authors.lastname: Zhao
authors.affiliation: a State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University , Guangzhou , China , and.
authors.forename: Jiangang
authors.initials: J
authors.lastname: Xu
authors.affiliation: a State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University , Guangzhou , China , and.
authors.forename: Kaili
authors.initials: K
authors.lastname: Wu
authors.affiliation: a State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University , Guangzhou , China , and.
authors.forename: Minbin
authors.initials: M
authors.lastname: Yu
mesh_terms: D000818:Animals; D001082:Aqueous Humor / Q000378:metabolism; D001682:Biological Availability; D002939:Ciprofloxacin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000378:metabolism; D003228:Conjunctiva / Q000378:metabolism; D003263:Contact Lenses, Hydrophilic; D003315:Cornea / Q000378:metabolism*; D003692:Delayed-Action Preparations / Q000008:administration & dosage* / Q000378:metabolism; D016503:Drug Delivery Systems / Q000379:methods; D005260:Female; D008297:Male; D009883:Ophthalmic Solutions / Q000008:administration & dosage* / Q000378:metabolism; D011102:Polyhydroxyethyl Methacrylate / Q000737:chemistry; D011817:Rabbits
chemical_list: D003692:Delayed-Action Preparations; D009883:Ophthalmic Solutions; D011102:Polyhydroxyethyl Methacrylate; C046067:pirfloxacin; D002939:Ciprofloxacin
keywords: Drug concentration; ocular drug delivery; pirfinedone; polymacon; soft contact lens