title: Preparation and in vitro characterization of pluronic-attached polyamidoamine dendrimers for drug delivery.
abstract: BACKGROUND
  Polyamidoamine (PAMAM) dendrimers have attracted lots of interest as drug carriers. And little study about whether pluronic-attached PAMAM dendrimers could be potential drug delivery systems has been carried on.
  
  
  OBJECTIVE
  Pluronic F127 (PF127) attached PAMAM dendrimers were designed as novel drug carriers.
  
  
  METHODS
  Two conjugation ratios of PF127-attached PAMAM dendrimers were synthesized. (1)H nuclear magnetic resonance ((1)H-NMR), Fourier transform infrared spectrum (FTIR), element analysis and ninhydrin assay were used to characterize the conjugates. Size, zeta potential and critical micelle concentrations (CMC) were also detected. And DOX was incorporated into the hydrophobic interior of the conjugates. Studies on their drug loading and drug release were carried on. Furthermore, hemolysis and cytotoxicity assay were used to evaluate the toxicity of the conjugates.
  
  
  CONCLUSIONS
  PF127 was successfully conjugated to the fifth generation PAMAM dendrimer at two molar ratios of 19% and 57% (PF127 to surface amine per PAMAM dendrimer molecular). The conjugates showed an increased size and a reduced zeta potential. And higher CMC values were obtained than pure PF127. Compared with unconjugated PAMAM dendrimer, PF127 conjugation significantly reduced the hemolytic toxicity and cytotoxicity of PAMAM dendrimer in vitro. The encapsulation results showed that the ability to encapsulate DOX by the conjugate of 19% conjugation ratio was better than that of 57% conjugation ratio. And the maximum is ∼12.87 DOX molecules per conjugate molecule. Moreover, the complexes showed a sustained release behavior compared to pure DOX.
  
  
  CONCLUSIONS
  Findings from the in vitro study show that the PF127-attached PAMAM dendrimers may be potential carriers for drug delivery.
authors.affiliation: Zhoushan Hospital, Zhoushan , P.R. China and.
authors.forename: Zhuojun
authors.initials: Z
authors.lastname: Gu
authors.forename: Meng
authors.initials: M
authors.lastname: Wang
authors.forename: Qiongyan
authors.initials: Q
authors.lastname: Fang
authors.forename: Huaiyu
authors.initials: H
authors.lastname: Zheng
authors.forename: Feiyue
authors.initials: F
authors.lastname: Wu
authors.forename: Dai
authors.initials: D
authors.lastname: Lin
authors.forename: Ying
authors.initials: Y
authors.lastname: Xu
authors.forename: Yi
authors.initials: Y
authors.lastname: Jin
mesh_terms: D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000008:administration & dosage / Q000737:chemistry / Q000633:toxicity; D002626:Chemistry, Pharmaceutical / Q000379:methods; D003692:Delayed-Action Preparations; D050091:Dendrimers / Q000737:chemistry*; D004317:Doxorubicin / Q000008:administration & dosage* / Q000737:chemistry / Q000633:toxicity; D004337:Drug Carriers / Q000737:chemistry; D016503:Drug Delivery Systems; D065546:Drug Liberation; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D061986:MCF-7 Cells; D009682:Magnetic Resonance Spectroscopy; D010316:Particle Size; D020442:Poloxamer / Q000737:chemistry*; D011817:Rabbits
chemical_list: D000903:Antibiotics, Antineoplastic; D003692:Delayed-Action Preparations; D050091:Dendrimers; D004337:Drug Carriers; C104700:PAMAM Starburst; D020442:Poloxamer; D004317:Doxorubicin
keywords: Conjugate; DOX; PAMAM dendrimer; drug delivery; pluronic F127; toxicity