Size of the pores created by an electric pulse: Microsecond vs millisecond pulses

作者：Saulis Gintautas^*; Saule Rita

来源：Biochimica et Biophysica Acta-Biomembranes, 2012, 1818(12): 3032-3039.

DOI：10.1016/j.bbamem.2012.06.018

• Electroporation
• Electropermeabilization
• Mouse hepatoma
• CHO cells
• Human erythrocytes

Here, the sizes of the pores created by square-wave electric pulses with the duration of 100 mu s and 2 ms are compared for pulses with the amplitudes close to the threshold of electroporation. Experiments were carried out with three types of cells: mouse hepatoma MH-22A cells, Chinese hamster ovary (CHO) cells, and human erythrocytes. In the case of a short pulse (square-wave with the duration of 100 mu s or exponential with the time constant of 22 mu s), in the large portion (30-60%) of electroporated (permeable to potassium ions) cells, an electric pulse created only the pores, which were smaller than the molecule of bleomycin (molecular mass of 1450 Da, r approximate to 0.8 nm) or sucrose (molecular mass of 342.3 Da, radius-0.4-4-0.52 nm). In the case of a long 2-ms duration pulse, in almost all cells, which were electroporated, there were the pores larger than the molecules of bleomycin and/or sucrose. Kinetics of pore resealing depended on the pulse duration and was faster after the shorter pulse. After a short 100-mu s duration pulse, the disappearance of the pores permeable to bleomycin was completed after 6-7 min at 24-26 degrees C, while after a long 2-ms duration pulse, this process was slower and lasted 15-20 min. Thus, it can be concluded that a short 100-mu s duration pulse created smaller pores than the longer 2-ms duration pulse. This could be attributed to the time inadequacy for pores to grow and expand during the pulse, in the case of short pulses.

• 出版日期2012-12