title: PEGylated multi-walled carbon nanotubes for encapsulation and sustained release of oxaliplatin.
abstract: OBJECTIVE
  To develop PEGylated multi-walled carbon nanotubes as a sustained release drug delivery system.
  
  
  METHODS
  Oxaliplatin was incorporated into inner cavity of PEGylated multi-walled carbon nanotubes (MWCNT-PEG) using nano-extraction. Oxaliplatin release rates from MWCNT-PEG-Oxaliplatin were investigated using dialysis tubing. Cytotoxicity of oxaliplatin, MWCNT-Oxaliplatin and MWCNT-PEG-Oxaliplatin were evaluated in HT29 cell by MTT assay, Pt-DNA adducts formation, γ-H2AX formation and cell apoptosis assay.
  
  
  RESULTS
  Loading of oxaliplatin into MWCNT-PEG was ~43.6%. Sustained release occurred to MWCNT-PEG-Oxaliplatin, with only 34% of oxaliplatin released into medium within 6 h. In MTT assay, MWCNT-PEG-Oxaliplatin showed slightly decreased cytotoxic effect when cell viability was assessed at 12 and 24 h. A drastic increase of cytotoxicity was found when cell viability was assessed at 48 and 96 h. Pt-DNA adducts formation, γ-H2AX formation and cell apoptosis assay results showed the same trend as the MTT assay, suggesting sustained-release for MWCNT-Oxaliplatin and MWCNT-PEG-Oxaliplatin formulations.
  
  
  CONCLUSIONS
  PEGylated multi-walled carbon nanotubes can be used as sustained release drug delivery system, thus remarkably improving cytotoxicity of oxaliplatin on HT-29 cells.
authors.affiliation: Department of Laboratory Medicine, Shandong Provincial Qianfoshan Hospital & Shandong University, 16766 Jingshi Road, Jinan, People's Republic of China, 250014.
authors.forename: Linlin
authors.initials: L
authors.lastname: Wu
authors.forename: Changjun
authors.initials: C
authors.lastname: Man
authors.forename: Hong
authors.initials: H
authors.lastname: Wang
authors.forename: Xiaohe
authors.initials: X
authors.lastname: Lu
authors.forename: Qinghai
authors.initials: Q
authors.lastname: Ma
authors.forename: Yu
authors.initials: Y
authors.lastname: Cai
authors.forename: Wanshan
authors.initials: W
authors.lastname: Ma
mesh_terms: D000970:Antineoplastic Agents / Q000008:administration & dosage* / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003110:Colonic Neoplasms / Q000188:drug therapy / Q000473:pathology; D018736:DNA Adducts / Q000187:drug effects; D003692:Delayed-Action Preparations / Q000737:chemistry*; D019073:HT29 Cells; D006801:Humans; D037742:Nanotubes, Carbon / Q000737:chemistry*; D009944:Organoplatinum Compounds / Q000008:administration & dosage* / Q000494:pharmacology; D000077150:Oxaliplatin; D011092:Polyethylene Glycols / Q000737:chemistry*
chemical_list: D000970:Antineoplastic Agents; D018736:DNA Adducts; D003692:Delayed-Action Preparations; D037742:Nanotubes, Carbon; D009944:Organoplatinum Compounds; D000077150:Oxaliplatin; D011092:Polyethylene Glycols