title: Radiofrequency-triggered release for on-demand delivery of therapeutics from titania nanotube drug-eluting implants.
abstract: OBJECTIVE
  This study aimed to demonstrate radiofrequency (RF)-triggered release of drugs and drug carriers from drug-eluting implants using gold nanoparticles as energy transducers.
  
  
  METHODS
  Titanium wire with a titania nanotube layer was used as an implant loaded with indomethacin and micelles (tocopheryl PEG succinate) as a drug and drug carrier model. RF signals were generated from a customized RF generator to trigger in vitro release.
  
  
  CONCLUSIONS
  Within 2.5 h, 18 mg (92%) of loaded drug and 14 mg (68%) of loaded drug carriers were released using short RF exposure (5 min), compared with 5 mg (31%) of drug and 2 mg (11%) of drug carriers without a RF trigger. Gold nanoparticles can effectively function as RF energy transducers inside titania nanotubes for rapid release of therapeutics at arbitrary times.
  
  
  CONCLUSIONS
  The results of this study show that RF is a promising strategy for triggered release from implantable drug delivery systems where on-demand delivery of therapeutics is required.
authors.affiliation: School of Chemical Engineering, The University of Adelaide, Engineering North Building, SA 5005, Australia.
authors.forename: Manpreet
authors.initials: M
authors.lastname: Bariana
authors.forename: Moom Sinn
authors.initials: MS
authors.lastname: Aw
authors.forename: Eli
authors.initials: E
authors.lastname: Moore
authors.forename: Nicolas H
authors.initials: NH
authors.lastname: Voelcker
authors.forename: Dusan
authors.initials: D
authors.lastname: Losic
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage*; D004343:Drug Implants / Q000737:chemistry*; D004867:Equipment Design; D006046:Gold / Q000737:chemistry; D007213:Indomethacin / Q000008:administration & dosage*; D053768:Metal Nanoparticles / Q000737:chemistry; D008823:Micelles; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure; D011846:Radio Waves; D014025:Titanium / Q000737:chemistry*; D014159:Transducers
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D004343:Drug Implants; D008823:Micelles; C009495:titanium dioxide; D006046:Gold; D014025:Titanium; D007213:Indomethacin
keywords: drug-eluting implant; gold nanoparticle; micelle; noninvasive drug delivery; polymer; radiofrequency; titania nanotube; triggered drug release; water-insoluble drug