The Effect of Nanosecond, High-Voltage Electric Pulses on the Shape and Permeability of Polymersome GUVs
- 223 Downloads
Polymersomes, vesicles composed of block copolymers, are promising candidates as membrane alternatives and functional containers, e.g., as potential carriers for functional molecules because of their stability and tunable membrane properties. In the scope of possible use for membrane protein delivery to cells by electrofusion, we investigated the cytotoxicity of such polymersomes as well as the effects of nanosecond electric pulses with variable repetition rate on the shape and permeability of polymersomes in buffers with different conductivities. The polymersomes did not show cytotoxic effects to CHO and B16-F1 cells in vitro in concentrations up to 250 µg/mL (for 48 h) or 1.35 mg/mL (for 60 min), which renders them suitable for interacting with living cells. We observed a significant effect of the pulse repetition rate on electrodeformation of the polymersomes. The electrodeformation was most pronounced in low conductivity buffer, which is favorable for performing electrofusion with cells. However, despite more pronounced deformation at higher pulse repetition rate, the electroporation performance of polymersomes was unaffected and remained in similar ranges both at 10 Hz and 10 kHz. This phenomenon is possibly due to the higher stability and rigidity of polymer vesicles, compared to liposomes, and can serve as an advantage (or disadvantage) depending on the aim in employing polymersomes such as stable membrane alternative architectures or drug vehicles.
KeywordsElectroporation Polymersomes Electrodeformation Nanosecond electric pulses Membrane alternatives
The study was supported by the Austrian Science Fund (FWF) and Slovenian Research Agency (ARRS)—Austrian-Slovenian Lead Agency Joint Project: Electroporation as Method for Inserting Functional Membrane Proteins in Mammalian Cells N2-0027 (2015-2017), and by Austrian-Slovenian Lead Agency Joint Project: Electroporation as Method for Inserting Functional Membrane Proteins in Mammalian Cells BI-AT/16-17-003 (2015-2017). It was conducted in the scope of the LEA EBAM: European Laboratory of Pulsed Electric Fields Applications in Biology and Medicine (2011-2018).
- Alberts B, Johnson A, Lewis J et al (2002) Ion channels and the electrical properties of membranes. In: Molecular biology of the cell, 4th edn. Garland Science, New York. Available from https://www.ncbi.nlm.nih.gov/books/NBK26910/
- Barltrop JA, Owen TC, Cory AH, Cory JG (1991) 5-(3-carboxymethoxyphenyl)-2-(4,5-dimethylthiazolyl)-3-(4-sulfophenyl)tetrazolium, inner salt (MTS) and related analogs of 3-(4,5-dimethylthiazolyl)-2,5-diphenyltetrazolium bromide (MTT) reducing to purple water-soluble formazans As cell-viability indicators. Bioorg Med Chem Lett 1:611–614. doi: 10.1016/S0960-894X(01)81162-8 CrossRefGoogle Scholar
- Erfani-Moghadam V, Nomani A, Zamani M et al (2014) A novel diblock of copolymer of (monomethoxy poly [ethylene glycol]-oleate) with a small hydrophobic fraction to make stable micelles/polymersomes for curcumin delivery to cancer cells. Int J Nanomed 9:5541–5554. doi: 10.2147/IJN.S63762 CrossRefGoogle Scholar
- Israelachvili JN (2011) Intermolecular and surface forces, 3rd edn. Academic Press, Santa BarbaraGoogle Scholar
- Jordan CA, Neumann E, Sowers AE (2013) Electroporation and electrofusion in cell biology. Springer Science & Business Media, New YorkGoogle Scholar
- Lodish H, Berk A, Zipursky SL et al (2000) Molecular cell biology, 4th edn. W. H. Freeman, New YorkGoogle Scholar
- Neumann E, Kakorin S, Toensing K (1998) Membrane electroporation and electromechanical deformation of vesicles and cells. Faraday Discuss 111:125–157Google Scholar