Fast Electrical Lysis of Cells for Capillary Electrophoresis

Abstract

In the past decade, capillary electrophoresis has demonstrated increasing utility for the quantitative analysis of single cells. New applications for the analysis of dynamic cellular properties demand sampling methods with sufficient temporal resolution to accurately measure these processes. In particular, intracellular signaling pathways involving many enzymes can be modulated on subsecond time scales. We have developed a technique to rapidly lyse an adherent mammalian cell using a single electrical pulse followed by efficient loading of the cellular contents into a capillary. Microfabricated electrodes were designed to create a maximum voltage drop across the flattened cell's plasma membrane at a minimum interelectrode voltage. The influence of the interelectrode distance, pulse duration, and pulse strength on the rate of cell lysis was determined. The ability to rapidly lyse a cell and collect and separate the cellular contents was demonstrated by loading cells with Oregon Green and two isomers of carboxyfluorescein. All three fluorophores were detected with a separation efficiency comparable to that of standards. Parallel comparison of electrical lysis to that produced by a laser-based lysis system revealed that the sampling efficiencies of the two techniques were comparable. Rapid cell lysis by an electrical pulse may increase the application of capillary electrophoresis to the study of cellular dynamics requiring fast sampling times.

A handheld preconcentrator for the rapid collection of cancerous cells using dielectrophoresis generated by circular microelectrodes in stepping electric fields

“…27,28 The field strength required for lysis of mammalian cells was in the order of magnitude of 10 6 V=m. 29 The electric field strength applied herein (approximate 5 Â 10 5 V=m, 1 MHz) was lower than the threshold strength of cell lysis to maintain the viability of cells. The fluorescent images of cells stained by calcein AM in Fig.…”

Analysis of Electric Fields inside Microchannels and Single Cell Electrical Lysis with a Microfluidic Device

“…These deviations, resulting in estimation errors if the expressions were derived in the last section for an ideal microchannel are applied for practical microchannels, should be taken under consideration for microfluidic devices involving generation of non-uniform electric fields. This is especially important for small lengths of microchannels, as reported in recent literature [6,8,[18][19][20][21][22][23][24][25][26][27]30]. Thus, the deviation of the mean values between the ideal and the practical model are of particular interest.…”

“…Electrical lysis is a phenomenon of complete cell membrane breakdown under a high electric field of a critical period [8,[16][17][18]. Reports of various types of cell lysis using an electrical field are available, including yeast cells, E. coli [19], cancer cells [20][21][22], mammalian cells [23], leukocytes [24], erythrocyte [25], red blood cells [8,26] and Chinese hamster ovary cells [6,27]. In this work, non-invasively collected cell debris, i.e., shredded cells, of epidermal tissue from human fingerprints are used as cell-samples.…”

Very High Throughput Electrical Cell Lysis and Extraction of Intracellular Compounds Using 3D Carbon Electrodes in Lab-on-a-Chip Devices

“…The rupture of the cell membrane can be performed by different means including chemical [3,4], electrical [5,6], mechanical [7,8] and optical [9,10]. The current benchmark in cell lysis is chemical lysis due to its easy implementation, which requires no dedicated equipment but only mixing with chemical reagents such as the CelLytic kit from Sigma-Aldrich.…”

“…Microfabrication techniques now make it possible to position electrodes very close to each other, therefore allowing for the creation of electrical fields up to kV/cm, strong enough to porate the cell membrane by dielectric breakdown, using voltages as low as tens of volts. Furthermore, the use of microelectrodes allows for the creation of miniaturized devices for cell lysis that feature low dead volumes, portability and can contain more modules, such as separation and detection [6], other than cell lysis. Previous work on cell lysis using miniaturized devices include that from Lu et al [12], Wang et al [11] and by some of us [13].…”