title: Synthesis and evaluation of perfluorooctylbromide nanoparticles modified with a folate receptor for targeting ovarian cancer: in vitro and in vivo experiments.
abstract: BACKGROUND
  Epithelial ovarian cancer is the leading cause of death among gynecologic malignancies. However, detecting ovarian cancer at an early stage remains challenging. In this work, we aimed to synthesize a folate-receptor-targeting perfluorooctylbromide nanoparticle (FR-TPNP) as a targeted computed tomography (CT) contrast agent for the early detection of ovarian cancer.
  
  
  METHODS
  Perfluorooctylbromide (PFOB) was encapsulated in Poly (lactic-co-glycolic acid) (PLGA) by a two-step emulsion technique to construct the nanoparticles. Folate-poly (ethylene glycol)-carboxylic acid (Fol-PEG-COOH) was introduced to modify the surface of the nanoparticles through attachment to the PLGA. The effects of different volume ratios of PFOB to PLGA on the characteristics of the FR-TPNP emulsions were compared. The size distribution and potential of the FR-TPNPs were assessed with a laser particle size analyzer system. The in vitro targeting ability of the FR-TPNPs was observed with a confocal laser scanning microscope (CLSM), and the in vivo transportation of the FR-TPNPs was evaluated with CT.
  
  
  RESULTS
  The sizes of the FR-TPNP emulsion with different volume ratios varied from 302.67 ± 27.83 nm to 563.68 ± 47.29 nm, and the mean CT value ranged from 233 ± 20.59 HU to 587.66 ± 159.51 HU. Both the size and mean CT value increased with the volume ratio. The FR-TPNPs showed greater cell affinity and targeting efficiency to SKOV3 cells than the control group and folic acid interference group in vitro, as observed by CLSM. A significant CT enhancement of ovarian cancer xenografts in the targeted group of a nude mice model was observed 2 h post-injection; it increased to a peak at 12 h and had a duration of 48 h. The mean CT value of the tumor in the targeted group was considerably higher than those in the non-targeted and other groups 6 h post-injection.
  
  
  CONCLUSIONS
  The synthesized FR-TPNP emulsion was an effective CT contrast agent with highly efficient targeting ability and a long circulation time, thus representing a potential strategy for the earlier detection of ovarian cancer.
authors: Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University No. 74 Linjiang Rd, Yuzhong District, Chongqing 400010, China.
authors: Xinjie
authors: X
authors: Liu
authors: Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University No. 74 Linjiang Rd, Yuzhong District, Chongqing 400010, China.
authors: Jiannong
authors: J
authors: Zhao
authors: Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University No. 74 Linjiang Rd, Yuzhong District, Chongqing 400010, China.
authors: Dajing
authors: D
authors: Guo
authors: Institute of Ultrasound Imaging, Department of Ultrasound, The Second Affiliated Hospital of Chongqing Medical University No. 74 Linjiang Rd, Yuzhong District, Chongqing 400010, China.
authors: Zhigang
authors: Z
authors: Wang
authors: Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University No. 74 Linjiang Rd, Yuzhong District, Chongqing 400010, China.
authors: Weixiang
authors: W
authors: Song
authors: Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University No. 74 Linjiang Rd, Yuzhong District, Chongqing 400010, China.
authors: Weijuan
authors: W
authors: Chen
authors: Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University No. 74 Linjiang Rd, Yuzhong District, Chongqing 400010, China.
authors: Jun
authors: J
authors: Zhou
keywords: Folate receptor; PFOB; ovarian cancer; targeting CT contrast agent