title: Phospholipids-based microbubbles sonoporation pore size and reseal of cell membrane cultured in vitro.
abstract: OBJECTIVE
  To investigate phospholipids-based microbubbles induced sonoporation and cell membrane reseal in vitro under various conditions.
  
  
  METHODS
  A breast cancer cell line SK-BR-3 was used to investigate ultrasonic sonoporation under various conditions. Atomic force microscopy (AFM) scanning techniques were employed to observe the change of membrane pores.
  
  
  RESULTS
  Normal SK-BR-3 cells membrane pores were evenly distributed and less than 1 microm. After ultrasound exposure, membrane pores were enlarged at different degree depending on ultrasound exposure durations, filling gas species and microbubble suspension concentration. With microbubble suspension concentration being increased to 5% or ultrasound exposure reached 30 s, membrane pores in fluorocarbon (C(3)F(8) or SF(6))-filled microbubble groups exceeded 1 microm, which were significantly larger than that of air-filled microbubble group. Membrane pores were about 2-3 microm under ultrasound 60 s with 5% fluorocarbon-filled microbubble suspension. After 24 h of incubation, most of the enlarged membrane pores could reseal to normal size, which corresponded to cell viability.
  
  
  CONCLUSIONS
  Membrane pores can be obviously enlarged by ultrasonic sonoporation of fluorocarbon-filled microbubbles, whose reseal time depended on ultrasound exposure duration and microbubble suspension concentration.
authors.affiliation: Department of Clinical Pharmacology, General Hospital of Beijing Military Command of PLA, Dong Si Shi Tiao Road, Dongcheng District, Beijing, People's Republic of China. lctuua@yahoo.com.cn
authors.forename: Ying-Zheng
authors.initials: YZ
authors.lastname: Zhao
authors.forename: Yu-Kun
authors.initials: YK
authors.lastname: Luo
authors.forename: Cui-Tao
authors.initials: CT
authors.lastname: Lu
authors.forename: Jing-Feng
authors.initials: JF
authors.lastname: Xu
authors.forename: Jie
authors.initials: J
authors.lastname: Tang
authors.forename: Mei
authors.initials: M
authors.lastname: Zhang
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Hai-Dong
authors.initials: HD
authors.lastname: Liang
mesh_terms: D002460:Cell Line; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000737:chemistry* / Q000648:ultrastructure*; D002470:Cell Survival / Q000502:physiology; D005260:Female; D005740:Gases; D006801:Humans; D018625:Microscopy, Atomic Force; D008863:Microspheres; D010743:Phospholipids / Q000737:chemistry*; D016062:Porosity; D011247:Pregnancy; D014465:Ultrasonics
chemical_list: D005740:Gases; D010743:Phospholipids