title: Carbon nanotubes part I: preparation of a novel and versatile drug-delivery vehicle.
abstract: BACKGROUND
  It is 23 years since carbon allotrope known as carbon nanotubes (CNT) was discovered by Iijima, who described them as "rolled graphite sheets inserted into each other". Since then, CNTs have been studied in nanoelectronic devices. However, CNTs also possess the versatility to act as drug- and gene-delivery vehicles.
  
  
  METHODS
  This review covers the synthesis, purification and functionalization of CNTs. Arc discharge, laser ablation and chemical vapor deposition are the principle synthesis methods. Non-covalent functionalization relies on attachment of biomolecules by coating the CNT with surfactants, synthetic polymers and biopolymers. Covalent functionalization often involves the initial introduction of carboxylic acids or amine groups, diazonium addition, 1,3-dipolar cycloaddition or reductive alkylation. The aim is to produce functional groups to attach the active cargo.
  
  
  CONCLUSIONS
  In this review, the feasibility of CNT being used as a drug-delivery vehicle is explored. The molecular composition of CNT is extremely hydrophobic and highly aggregation-prone. Therefore, most of the efforts towards drug delivery has centered on chemical functionalization, which is usually divided in two categories; non-covalent and covalent. The biomedical applications of CNT are growing apace, and new drug-delivery technologies play a major role in these efforts.
authors.affiliation: Iran University of Medical Sciences, School of Advanced Technologies in Medicine, Department of Nanotechnology , Tehran , Iran.
authors.forename: Mahdi
authors.initials: M
authors.lastname: Karimi
authors.forename: Navid
authors.initials: N
authors.lastname: Solati
authors.forename: Mohammad
authors.initials: M
authors.lastname: Amiri
authors.forename: Hamed
authors.initials: H
authors.lastname: Mirshekari
authors.forename: Elmira
authors.initials: E
authors.lastname: Mohamed
authors.forename: Mahdiar
authors.initials: M
authors.lastname: Taheri
authors.forename: Mahshid
authors.initials: M
authors.lastname: Hashemkhani
authors.forename: Ahad
authors.initials: A
authors.lastname: Saeidi
authors.forename: Mehrdad Asghari
authors.initials: MA
authors.lastname: Estiar
authors.forename: Parnian
authors.initials: P
authors.lastname: Kiani
authors.forename: Amir
authors.initials: A
authors.lastname: Ghasemi
authors.forename: Seyed Masoud Moosavi
authors.initials: SM
authors.lastname: Basri
authors.forename: Amir R
authors.initials: AR
authors.lastname: Aref
authors.forename: Michael R
authors.initials: MR
authors.lastname: Hamblin
mesh_terms: D016503:Drug Delivery Systems; D018014:Gene Transfer Techniques; D015316:Genetic Therapy / Q000379:methods; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D037742:Nanotubes, Carbon; D004364:Pharmaceutical Preparations / Q000008:administration & dosage*
chemical_list: D037742:Nanotubes, Carbon; D004364:Pharmaceutical Preparations
keywords: addition reaction; carbon nanotubes; functional group; functionalization; purification; synthesis