Quantitative study of molecular transport due to electroporation: uptake
of bovine serum albumin by erythrocyte ghosts.
Prausnitz MR; Milano CD; Gimm JA; Langer R; Weaver JC Biophys J (A5S), 1994 May; 66 (5): 1522-30
Electroporation is believed to involve the creation of
aqueous pathways in lipid bilayer membranes by transient
elevation of the transmembrane voltage to approximately 1 V.
Here, results are presented for a quantitative study of the
number of bovine serum albumin (BSA) molecules transported
into erythrocyte ghosts caused by electroportion. 1) Uptake
of BSA was found to plateau at high field strength. However,
this was not necessarily an absolute maximum in transport.
Instead, it represented the maximum effect of increasing
field strength for a particular pulse protocol. 2) Maximum
uptake under any conditions used in this study corresponded
to approximately one-fourth of apparent equilibrium with the
external solution. 3) Multiple and longer pulses each
increased uptake of BSA, where the total time integral of
field strength correlated with uptake, independent of inter-
pulse spacing. 4) Pre-pulse adsorption of BSA to ghost
membranes appears to have increased transport. 5) Most
transport of BSA probably occurred by electrically driven
transport during pulses; post-pulse uptake occurred, but to
a much lesser extent. Finally, approaches to increasing
transport are discussed.