title: Gamma sterilization of diclofenac sodium loaded- N-trimethyl chitosan nanoparticles for ophthalmic use.
abstract: This study was conducted to investigate the effect of gamma irradiation on physicochemical properties of N-trimethyl chitosan (TMC), diclofenac sodium (DC) and diclofenac sodium loaded N-trimethylchitosan nanoparticles (DC-TMCNs), and to determine suitable doses of gamma rays for sterilization of DC-TMCNs. Physicochemical properties of TMC, DC and DC-TMCNs before and after exposure to gamma rays at various doses were investigated. It was found that gamma irradiation at doses of 5-25kGy did not cause any significant changes in physical and chemical properties of TMC, DC and DC-TMCNs. The bioburden of DC-TMCNs was 1.5×106CFU/vial. The initial contaminating bacteria were radiosensitive bacteria. A number of microorganisms was reduced to 10-6after exposure to 9.9kGy of gamma rays. Therefore, DC-TMCNs could be sterilized by gamma irradiation at a dose of 10kGy, which did not alter their physicochemical properties and did not produce any substances toxic to the eye.
authors.affiliation: Department of Pharmaceutical Sciences, Faculty of Pharmacy, Thammasat University, Pathum Thani 12120, Thailand. Electronic address: rathapona@hotmail.com.
authors.forename: Rathapon
authors.initials: R
authors.lastname: Asasutjarit
authors.affiliation: Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Rangsit University, Pathum Thani 12000, Thailand.
authors.forename: Thitaree
authors.initials: T
authors.lastname: Theerachayanan
authors.affiliation: Group of Research and Development, Thailand Institute of Nuclear Technology (Public Organization), Nakhon Nayok 26120, Thailand.
authors.forename: Prartana
authors.initials: P
authors.lastname: Kewsuwan
authors.affiliation: National Center For Genetic Engineering and Biotechnology, National Science and Technology Development Agency (NSTDA), Thailand Science Park, Pathum Thani 12120, Thailand.
authors.forename: Sukitaya
authors.initials: S
authors.lastname: Veeranondha
authors.affiliation: National Metal and Materials Technology Center, National Science and Technology Development Agency (NSTDA), Thailand Science Park, Pathum Thani 12120, Thailand.
authors.forename: Asira
authors.initials: A
authors.lastname: Fuongfuchat
authors.affiliation: Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Garnpimol C
authors.initials: GC
authors.lastname: Ritthidej
mesh_terms: D060433:Administration, Ophthalmic; D000818:Animals; D002460:Cell Line; D048271:Chitosan; D003315:Cornea / Q000166:cytology; D004008:Diclofenac / Q000737:chemistry*; D053758:Nanoparticles; D009883:Ophthalmic Solutions; D011817:Rabbits; D013242:Sterilization
chemical_list: C118071:N-trimethyl chitosan chloride; D009883:Ophthalmic Solutions; D004008:Diclofenac; D048271:Chitosan
keywords: Diclofenac sodium; Gamma irradiation; N-Trimethyl chitosan nanoparticles; Ophthalmic drug delivery; Sterilization