title: The preparation and characterization of folate-conjugated human serum albumin magnetic cisplatin nanoparticles.
abstract: OBJECTIVE
  Nanoparticles are becoming an important method of targeted drug delivery. To evaluate the importance of folate-conjugated human serum albumin (HSA) magnetic nanoparticles (Folate-CDDP/HSA MNP), we prepared drug-loaded Folate-CDDP/HSA MNPs and characterized their features.
  
  
  METHODS
  First, folate was conjugated with HSA under the effect of a condensing agent, and the conjugating rate was evaluated by a colorimetric method using 2, 4, 6 - trinitrobenzene sulfonic acid. Second, under N2 gas, Fe3O4 magnetic nanomaterials were prepared and characterized by using transmission electron microscopy (TEM), SEM-EDS and X-ray diffraction (XRD). Finally, Folate-CDDP/HSA MNP was prepared by using a solvent evaporation technique. TEM was used to observe particle morphology. The particle size and distribution of the prepared complexes were determined by a Laser particle size analyzer. Drug loading volume and drug release were investigated by a high performance liquid chromatography method (HPLC) in vitro.
  
  
  RESULTS
  We successfully prepared folate-conjugated HSA and its conjugating rate was 27.26 µg/mg. Under TEM, Fe3O4 magnetic nanoparticles were highly electron density and had an even size distribution in the range of 10-20 nm. It was confirmed by SEM-EDS and XRD that Fe3O4 magnetic nanoparticles had been successfully prepared. Under TEM, drug-loaded magnetic nanoparticles were observed, which had a round shape, similar uniform size and smooth surface. Their average size was 79 nm which was determined by laser scattering, and they exhibited magnetic responsiveness. Encapsulation efficiency was 89.75% and effective drug loading was calculated to be 15.25%. The release results in vitro showed that the half release time (t½) of cisplatin in cisplatin Solution and Folate-CDDP/HSA MNP was 65 min and 24 h respectively, which indicated that microspheres had an obvious effect of sustained-release.
  
  
  CONCLUSIONS
  Folate-CDDP/HSA MNPs were prepared successfully. The preparation process and related characteristics data provided a foundation for further study, including the mechanism of the nanoparticles distribution in vivo and their intake by tumor cells.
authors.affiliation: Key Laboratory of Reproductive Medicine, Institute of Toxicology, Nanjing Medical University, Nanjing, 210042, China ; Clinical Laboratory ,Wuxi Hospital for Maternal and Child Health Care Affiliated Nanjing Medical University, Wuxi, Jiangsu,214002, China.
authors.forename: Daozhen
authors.initials: D
authors.lastname: Chen
authors.forename: Qiusha
authors.initials: Q
authors.lastname: Tang
authors.forename: Wenqun
authors.initials: W
authors.lastname: Xue
authors.forename: Jingying
authors.initials: J
authors.lastname: Xiang
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.forename: Xinru
authors.initials: X
authors.lastname: Wang
keywords: albumin magnetic nanoparticles; cisplatin; conjugate; folate
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