High-voltage Pulsed Electric Field Research Articles

Effects of high voltage pulsed electric field on structural properties and immune reactivity of arginine kinase in Fenneropenaeus chinensis

To evaluate the effect of high voltage pulsed electric field (PEF) treatment (10–20 kV/cm, 5–15 min) on the structural characteristics and sensitization of crude extracts of arginine kinase from Fenneropenaeus chinensis. By simulated in vitro gastric juice digestion (SGF), intestinal juice digestion (SIF) and enzyme-linked immunosorbent assay (ELISA), AK sensitization was reduced by 42.5% when treated for 10 min at an electric field intensity of 15 kV/cm. After PEF treatment, the α-helix content decreased, and the α-helix content gradually changed to β-sheet and β-turn. Compared to the untreated group, the surface hydrophobicity increased and the sulfhydryl content decreased. SEM and AFM analyses showed that the treated sample surface formed a dense porous structure and increased roughness. The protein content, dielectric properties, and amino acid content of sample also changed significantly with the changes in the treatment conditions. Non-thermal PEF has potential applications in the development of hypoallergenic foods.

System-Based Protection Method for High-Voltage Pulse Generator Switching Units in Biomass Electroporation

Background High-voltage pulsed electric field (PEF) technology has emerged as a promising technique for enhancing cell membrane permeabilization for biotechnological and medical applications. Given the parametric instability and low resistivity of biomass when used it as an electrical load, it is imperative for the switching unit to meet specific requirements in terms of load capacity and protection against overloads and short circuits. Methods To construct generators capable of producing high-voltage pulses in the microsecond and millisecond duration ranges, we are incorporating a switching unit that employs a hardware-software method to safeguard critical transistors against overloads and short-circuit currents. Our strategy revolves around utilizing the energy storage capacitor (ESC) both as a means of energy storage and as a current sensor. By monitoring the voltage drop during discharge, we can accurately estimate current parameters. The occurrence of an excessively rapid discharge from the ESC serves as an indicator of a short circuit. The microcontroller calculates ESC discharge limits based on preset parameters within a defined timeframe. Should this limit be exceeded, the system promptly interrupts to address the pulse responsible for the short circuit and halts the further supply of remaining pulses to the load. This sophisticated approach ensures the protection and integrity of the system in the face of potential overloads or short circuits. Results Applying a systemic approach in the design of the presented implementation of protection for key transistors in the switching node from overload and short-circuit current for high-voltage pulse generators (HVPG) in the microsecond and millisecond duration ranges allows for a simpler circuit solution. In this case, the system approach also provides a unified control principle when implementing the considered option for organizing protection, regardless of the number and type of transistors or solid-state switching modules used and connected in parallel. Conclusions The configuration and protective circuitry presented in the article are specifically tailored for shielding switching elements from short-circuit currents, with a primary focus on their application in high-voltage pulse generators (HVPG). These generators are commonly employed in the high-voltage pulse treatment of diverse and unstable loads during the electroporation of biomass. The technical solution expounded in the article is intended for use in the switching nodes of HVPG, particularly those with discharge circuits constructed based on a direct capacitive discharge scheme. Notably, this protection configuration introduces local innovation and is characterized by the circuit's simplicity, achieved through the effective utilization of existing system resources. This protective variant for HVPG switches is particularly well-suited for devices utilized in versatile technological installations with relatively lower performance levels.

High voltage pulsed electric field and electroporation technologies for algal biomass processing

High voltage pulsed electric field and electroporation technologies for algal biomass processing

Scheduled dosage regimen by irreversible electroporation of loaded erythrocytes for cancer treatment.

Precise control of cargo release is essential but still a great challenge for any drug delivery system. Irreversible electroporation (IRE), utilizing short high-voltage pulsed electric fields to destabilize the biological membrane, has been recently approved as a non-thermal technique for tumor ablation without destroying the integrity of adjacent collagenous structures. Due to the electro-permeating membrane ability, IRE might also have great potential to realize the controlled drug release in response to various input IRE parameters, which were tested in a red blood cell (RBC) model in this work. According to the mathematical simulation model of a round biconcave disc-like cell based on RBC shape and dielectric characteristics, the permeability and the pore density of the RBC membrane were found to quantitatively depend on the pulse parameters. To further provide solid experimental evidence, indocyanine green (ICG) and doxorubicin (DOX) were both loaded inside RBCs (RBC@DOX&ICG) and the drug release rates were found to be tailorable by microsecond pulsed electric field (μsPEF). In addition, μsPEF could effectively modulate the tumor stroma to augment therapy efficacy by increasing micro-vessel density and permeability, softening extracellular matrix, and alleviating tumor hypoxia. Benefiting from these advantages, this IRE-responsive RBC@DOX&ICG achieved a remarkably synergistic anti-cancer effect by the combination of μsPEF and chemotherapy in the tumor-bearing mice model, with the survival time increasing above 90 days without tumor burden. Given that IRE is easily adaptable to different plasma membrane-based vehicles for delivering diverse drugs, this approach could offer a general applicability for cancer treatment.

System-Based Protection Method for High-Voltage Pulse Generator Switching Units in Biomass Electroporation

Background High-voltage pulsed electric field (PEF) technology has emerged as a promising technique for enhancing cell membrane permeabilization for biotechnological and medical applications. Given the parametric instability and low resistivity of biomass when used as an electrical load, it is imperative for the switching unit to meet specific requirements in terms of load capacity and protection against overloads and short circuits. Methods We introduce a novel system for safeguarding against overload and short-circuit currents by optimizing existing hardware-software resources. Our approach hinges on using the energy storage capacitor (ESC) both for energy storage and as a current sensor. By monitoring voltage drop during discharge, we estimate current parameters. Rapid discharge signals a short circuit. The microcontroller calculates ESC discharge limits based on preset parameters within a defined timeframe. If this limit is surpassed, the system promptly halts current pulses and discontinues supply to the load, ensuring reliable protection for the switching unit. Results By employing a system-based protection approach, we are able to reduce the complexity of circuit design, thereby enabling a unified control strategy that remains consistent regardless of the number and type of transistors used. This approach eliminates the need for separate circuit solutions to address this issue. Conclusions By utilizing a system method to protect the switching elements from short-circuit currents, we established a unified system structure for the circuit protection that is independent of current surges at the pulse fronts, as well as the specific number and type of transistors and switching modules employed. This method not only enhances the efficiency and reliability of the technology but also simplifies the design process and ensures a unified approach to protection, regardless of the system's configuration.

畜禽舍空间相控分裂导线复合除尘杀菌装置设计研究

Livestock scale breeding is the inevitable trend of future livestock and poultry husbandry. Closed breeding requires excellent environment and livestock and poultry housings contain a lot of dust, pathogenic microorganisms and harmful gases, affecting the health of livestock and poultry and breeding personnel. Most of the common sterilization and dust collection devices for livestock and poultry housings on the market are too high energy consumption, and easy to cause secondary pollution. Therefore, an environmental purification device was designed to absorb dust in the air and kill harmful bacteria by using high voltage pulsed electric field. The device was designed using phase control principle and bundled conductor. COMSOL Multiphysics software was used to simulate the layout of single conductor, twin bundled conductor and quad bundled conductor. It was found that when the conductor was designed as twin bundled conductor or quad bundled conductor, the gradient distribution of spatial electric field intensity was more uniform and the downward trend of electric field was slower, which could effectively improve the dust collection and sterilization efficiency of the device. At the same time, a variety of electric field environments can be set up by using phase difference to meet different environmental requirements of livestock and poultry. The compound dust collection and sterilization device with phase-controlled bundled conductor for livestock and poultry housing space includes high voltage pulse generator, bundled conductor, high voltage special timer, insulator and other parts, which can effectively reduce the dust content in the air, the concentration of pathogenic bacteria, harmful gases, etc. after assembly test and can also reduce the humidity in the livestock and poultry housings.

低频高压脉冲电场对陈年水稻种子萌发特性的影响

In this study, the effects of different electric field parameters on the germination characteristics of aged rice seeds were determined via low-frequency high-voltage pulsed electric field (LH-PEF) treatment. The Design-Expert software was used to design a rotating combination test, and response surface analysis was used to optimize five germination characteristics of rice seeds. The optimal treatment voltage was 13 kV and the optimal treatment time was 32.72 min. The results show that, under the optimal treatment conditions (P<0.01), the germination potential (GE), germination rate (GP), germination index (GI), vitality index (VI) and high vitality ratio (HVR) of the aged rice seeds increased by 23.7%, 17.7%, 43.2%, 59.7%, and 250%, respectively, compared to the control. The pulsed electric field’s biological effect on the aged rice seeds was the most significant when the optimal treatment parameters were used. The results of this study provide a reliable reference for the parameter optimization of high-voltage electric field treatment of crop seeds.

Simulation of High-voltage Pulse Generator for Environment-friendly, Non-thermal Pasteurization Applications

Nowadays, the demand for high-voltage pulse generators has begun to proliferate in many industries. Particularly in the food processing industries, the conventional method of pasteurization involves the use of heat treatment processes, which are not environment-friendly; hence, researchers are working towards environment-friendly, non-thermal food processing techniques by which the microorganisms present in the liquid food can be eliminated. High-voltage pulsed electric field technology is one of the popular non-thermal food processing techniques. Recent advancements in power electronic switching technology have facilitated the development of solid-state pulse generators for these applications. In this paper, the simulation of a high-voltage pulse generator for eco-friendly pasteurization applications has been attempted using a cascaded boost converter topology. The entire simulation is carried out using MATLAB/Simulink software. The designed two-stage cascaded boost converter is tested for varying duty cycles and loads. The results with resistive and inductive loads have been analyzed.

Eradication of Enterobaracter aerogenes, Escherichia coli, Listeria monocytogene, Staphylococcus aurous, and Acetobacter by High Voltage Pulsed Electric Field in Water and Milk Samples

ABSTRACT: Ensuring food and water safety has always been a health challenge globally. The present papers underscores HV-PEF (High Voltage Pulsed Electric Field), a novel approach to eliminate five kinds of microbes prevalent in milk and water in fractions of a second. These microorganisms are Enterobaracter aerogenes, Escherichia coli, Listeria monocytogene, Staphylococcus aurous, and Acetobacter. Objective was to find out the impact of HV-PEF on survival of selected species of bacteria, which are often considered as a concern for water and milk safety. A laboratory experimental setup was designed for producing HV-PEF, which was applied on sample of water and milk. The water sample was obtained from tap, and the milk sample was obtained from Bubalus bubalis. The microbial count was measured by plate method for both samples pre and post exposure to the HV-PEF. The effect was measured with combinations of varying field intensity and number of pulses, the intensity of the field having the highest value of 180 kV/cm (kilovolt-per-centimeter), and the pulse count varied between one to one hundred. Results showed, the endurance of few species was extremely low, at 40 kV filed intensity and 40 pulses. Other microbes also demonstrated low survival ratio (SR) at more than 40kV with pulses-count above 40. Complete inactivation of E. coli was achieved at around 80kV. The inactivation of microbe by HV-PEF varies with morphology and shape of the microorganisms. The annihilation of microorganisms is due to the rupturing of cell wall of microbe by the effect of HV-PEF, instead of ohmic heating (resistance induced).

Combined removal experiment of multiple impurities from W/O emulsions under high frequency pulsed electric field: Study on laws of desalination, decalcification, and deacidification

AbstractElectrocoalescence is widely used to dehydrate crude oil, but impurities in crude oil are extremely complex, which greatly weaken the effect of dehydration. To understand the coupling law of various impurities, a static demulsification experiment was conducted under a high frequency and high voltage pulsed electric field to investigate the effects of electric field parameters (voltage, frequency, pulse width ratio), emulsification strength, electrocoalescence time, water content, acid value, injection alkali ratio, calcium content, decalcification agent concentration and removal process on desalination, decalcification, and deacidification. The results showed that the desalination and decalcification rates varied synchronously with the electric field parameters and water content. Additionally, the desalination and decalcification rates decreased with the emulsification strength, alkali injection ratio, acid value, and calcium content. Further, they increased first and then decreased with decalcifier concentration. The deacidification rate did not vary with the electric field parameters, but it strengthened with the water content and alkali injection ratio. Conversely, it decreased with the acid value, calcium content, and decalcifier concentration. Additionally, it increased first and then decreased with the emulsification intensity. The best removal procedure is deacidification followed by decalcification. These findings are helpful to achieve the combined removal of various impurities in crude oil.

Cytoskeletal Remodeling and Gap Junction Translocation Mediates Blood-Brain Barrier Disruption by Non-invasive Low-Voltage Pulsed Electric Fields.

High-voltage pulsed electric fields (HV-PEF) delivered with invasive needle electrodes for electroporation applications is known to induce off-target blood-brain barrier (BBB) disruption. In this study, we sought to determine the feasibility of minimally invasive PEF application to produce BBB disruption in rat brain and identify the putative mechanisms mediating the effect. We observed dose-dependent presence of Evans Blue (EB) dye in rat brain when PEF were delivered with a skull mounted electrode used for neurostimulation application. Maximum region of dye uptake was observed while using 1500V, 100 pulses, 100µs and 10Hz. Results of computational models suggested that the region of BBB disruption was occurring at thresholds of 63V/cm or higher; well below intensity levels for electroporation. In vitro experiments recapitulating this effect with human umbilical vein endothelial cells (HUVEC) demonstrated cellular alterations that underlie BBB manifests at low-voltage high-pulse conditions without affecting cell viability or proliferation. Morphological changes in HUVECs due to PEF were accompanied by disruption of actin cytoskeleton, loss of tight junction protein-ZO-1 and VE-Cadherin at cell junctions and partial translocation into the cytoplasm. Uptake of propidium iodide (PI) in PEF treated conditions is less than 1% and 2.5% of total number of cells in high voltage (HV) and low-voltage (LV) groups, respectively, implying that BBB disruption to be independent of electroporation under these conditions. 3-D microfabricated blood vessel permeability was found to increase significantly following PEF treatment and confirmed with correlative cytoskeletal changes and loss of tight junction proteins. Finally, we show that the rat brain model can be scaled to human brains with a similar effect on BBB disruption characterized by electric field strength (EFS) threshold and using a combination of two bilateral HD electrode configurations.

Recent advances in electrochemical sterilization

Pathogenic bacteria have been throwing great threat on human health for thousands of years, so their sterilization is imperative. Electrochemical sterilization, as an emerging technology for sterilization in wastewater through direct and indirect effect of electric field, is receiving increasing attentions due to their effectiveness, simpleness and cost-effectiveness, compared with the traditional thermal methods. According to different sterilization devices and sterilization voltages used in sterilization, electrochemical sterilization methods are divided into high-voltage pulsed electric field (PEF) sterilization and electrocatalytic sterilization in this review. High-voltage PEF sterilization can change the permeability of cell membrane and thus form irreversible electroporation under high-voltage electric fields to inactivate bacteria while electrocatalytic sterilization mainly inactivates bacteria through direct oxidation, indirect oxidation, electroporation and electric field destruction. In order to provide the researchers with latest progress of electrochemical sterilization, typical materials applied in high-voltage PEF sterilization and electrocatalytic sterilization in the last five years are summarized. Moreover, present difficulties and future directions for their applications are also discussed. It could provide guidance for the new researchers on the study of electrochemical sterilization methods for rapid, effective sterilization in practical applications.

The design of a high-voltage pulsed electric field (hpef) device for non-liquid materials based on microcontroller

High-voltage pulsed electric field (HPEF) is one of the technologies applied in the food industry with the principle of non-heat treatment with a short pre-treatment time and no pollution is produced. The main benefit of this tool is to kill microbes in the food industry. In addition to non-thermal sterilization, HPEF can also be used for electroporation. Cell electroporation is the application of an electric voltage to the cell. The cells are damaged (broken/porous) without destroying the bioactive components present in the cells. Previous studies have shown that materials treated with HPEF increase the yield when distilled. It can occur due to the electroporation process, namely the breakdown of the oil cell network, so that the distillation process is efficient (can reduce distillation time and increase the quantity of oil). The care box is designed with dimensions of 60cm x 40cm x 30cm which is made of acrylic material. The electrodes used a 60cm x 40cm plate mounted on a linear drive to adjust the treatment distance. HPEF uses a 15kV neon sign transformer. The transformer input frequency setting is set with a dimmer. A microcontroller is installed to adjust the shock period on the electrodes. Based on trials, the device can be used for various solid materials with different volumes.

Development of a High-Voltage Pulsed Electric Field Sterilization Power Supply Using a New Topology Circuit

Traditional thermal sterilization technology is easy to implement and safe, but it will destroy food nutrition and change food taste. Therefore, people began to turn their attention to non-thermal sterilization. High-voltage pulsed electric field sterilization technology is one of them; it has attracted much attention because of its high efficiency and little damage to food. Different types of loads will cause serious trailing of the pulse falling edge. In view of this situation, this paper proposes a new topology circuit that combines a solid-state switch with a half-bridge Marx generator. It can be used for high-voltage pulsed electric field sterilization. By improving the structure of the classical Marx circuit, the high-voltage pulse power supply of the new topology circuit has the characteristics of steep rising edge and short falling edge delay; does not require isolation inductance or isolation resistance, which solves the isolation problem between the DC charging power supply and the high-voltage terminal; and has a good voltage-clamping function and load adaptability. The working process of the topology circuit under resistive, capacitive and inductive loads and the voltage clamping effect when the solid-state switch does not work properly in the discharge process are analyzed in detail. The power supply is composed of an adjustable DC power supply, five-stage half-bridge Marx generator and control protection circuit. A field programmable gate array (FPGA) is used as the controller to generate control signals, and optical fiber isolation is used to provide control signals for the main loop. The power supply can output a high-voltage square wave pulse with a voltage amplitude of 10 kV, maximum pulse number of 1000 per second, maximum pulse width of 20 μs, pulse rise time of smaller than 300 ns and short pulse drop time, and the repeated voltage amplitude, frequency and pulse width are adjustable, which can meet the requirements of a high-voltage pulse sterilization experiment.

Investigation of Consequences of High-Voltage Pulsed Electric Field and TGase Cross-Linking on the Physicochemical and Rheological Properties of Pleurotus eryngii Protein.

This study aimed to evaluate the effects of high-voltage pulsed electric fields (HPEF) and transglutaminase (TGase) cross-clinking on the physicochemical and rheological properties of Pleurotus eryngii protein (PEP). The results showed that HPEF increased α-helixes and β-turns but decreased β-folds. A HPEF at 1500 V/cm maximized the free sulfhydryl content and solubility of PEP. TGase formed high-molecular-weight polymers in PEP. TGase at 0.25% maximized the free sulfhydryl groups, particle size, and solubility; shifted the maximum absorption wavelength from 343 nm to 339 nm and 341 nm; increased α-helixes and β-turns and decreased β-folds; and showed better rheological properties. Compared with TGase cross-linking, HPEF-1500 V/cm and 1% TGase significantly reduced the free sulfhydryl groups, particle size, and solubility, produced more uniform network structures, and improved the rheological properties. These results suggest that HPEF can increase the cross-linking of TGase and improve rheological properties of TGase-cross-linked PEP by affecting the physicochemical properties.

Law of diffusion bubbles produced by high-voltage pulsed electric field in liquid

Pulsed electric field is a novel physical energy source for treating atrial fibrillation and tumor ablation, which has advantages over traditional thermal ablation, such as being non-thermal, short treatment time, tissue selectivity, and low contact pressure requirements. The diffusion bubbles generated during physical ablation may lead to gas embolism and silent cerebral events, with potential hazards such as tissue damage and cerebral ischemia. Previous studies have shown that the number of bubbles generated is correlated with the electrical properties of the treated object, pulse parameters (pulse waveform, treatment time and input energy), and electrodes. The number of bubbles are more significant at the cathode than at the anode, and the number of bubbles positively correlates with the input energy. However, to the best of our knowledge, no studies have been conducted to investigate the effects of ablation pulse parameters on diffusion bubbles. Therefore, in our experiment, a platform for producing pulses and observing diffusion bubble is built, and the needle-ring electrode we made realizes the capture and measurement of diffusion bubbles. Since pulses with a voltage of 3 kV and a pulse width of 100 μs are commonly used as ablation parameters for atrial fibrillation and tumor in pulsed field ablation (PFA), the pulse width of unipolar pulse is selected as 5, 10, 50, and 100 μs, and the number of pulses applied is 1. The pulse voltage is determined according to the parameters commonly used in PFA and the simulation calculation of the field strength distribution of the needle-ring electrode. After determining the parameters, this experiment explicitly investigates the relationships among diffusion bubbles and solution conductivity, pulse voltage, pulse width, input energy, and other parameters. Meanwhile, the size distributions of diffusion bubbles under different operating conditions are statistically investigated. Besides, the possible causes of diffuse bubbles are also explored. We evaluate the number of bubbles by measuring the cross-sectional area of the diffusion bubbles from a top-down perspective. The experimental results show that the area of diffusion bubbles generated in the liquid is positively correlated with pulse voltage and input energy; high conductivity and long pulse width can enhance the thermal effect and increase the area of diffusion bubbles; diffusion bubbles with a diameter larger than 100 μm are easily generated under high conductivity and high pulse width conditions. By speculating on the results, the electrolytic reaction may be the main source of diffusion bubbles when the needle electrode is the cathode. This study is expected to optimize future pulsed electric field ablation parameters.

Enzymatic cell wall degradation combined with pulsed electric fields increases yields of water-soluble-protein extraction from the green marine macroalga Ulva sp.

Marine macroalgae are an attractive source of alternative protein. However, protein extraction from macroalgae is challenging. In this work, we investigated a combination of enzymatic cell wall degradation and high voltage Pulsed Electric Fields (PEF), to enhance yields of water-soluble-protein extraction from the green marine macroalga Ulva sp. The combined process showed a considerably higher protein extraction yield (19.6 ± 0.33%) compared to that of PEF alone (10.8 ± 0.37%) and enzyme pretreatment alone (9.7 ± 0.42%). Moreover, the water-soluble-protein extract obtained by PEF, which followed enzymatic cell wall degradation, had significant antioxidant activity. These results indicate that PEF combined with enzymatic pretreatment could contribute to protein extraction yields from Ulva sp., as a part of sustainable seaweed biorefinery. Industrial relevanceAlthough several previous works reported on methods for protein extraction from seaweeds for food application, the commercialization of the seaweed proteins is challenging due to multiple challenges in the extraction process development. In this work we show that a combination of enzymes for cell wall degradation with high voltage pulsed electric fields for membrane permeabilization lead to higher yields of water-soluble proteins. Both enzyme treatment and PEF are scalable processes, which do not modify proteins chemically, potentially leading to higher quality of the extract in comparison to standard alkaline extraction with a need to treat chemical waste.

Reversible and Irreversible Effects of Electroporation on Contractility and Calcium Homeostasis in Isolated Cardiac Ventricular Myocytes.

Irreversible electroporation is an energy form utilizing high-voltage pulsed electric field, leading to cellular homeostasis disruption and cell death. Recently, irreversible electroporation has shown promising results for the treatment of cardiac arrhythmias. However, reversible and irreversible effects of pulsed electric field on cardiac myocytes remain poorly understood. Here, we evaluated the influence of a monophasic single electric pulse (EP) on the contractility, Ca2+ homeostasis and recovery of cardiac myocytes. Isolated rat left ventricular myocytes were electroporated using single monophasic EP of different durations and voltages. Sarcomere length and intracellular Ca2+ were simultaneously monitored for up to 20 minutes after EP application in Fura-2 loaded left ventricular myocytes. Lethal voltage thresholds were determined using 100 µs and 10 ms pulses and by discriminating cell orientation with respect to the electric field. Electroporation led to an immediate increase in intracellular Ca2+ which was dependent upon the voltage delivered to the cell. Intermediate-voltage EP (140 V, 100 µs) increased sarcomere shortening, Ca2+ transient amplitude, and diastolic Ca2+ level measured 1 minute post-EP. Although sarcomere shortening returned to pre-EP level within 5 minutes, Ca2+ transient amplitude decreased further below pre-EP level and diastolic Ca2+ level remained elevated within 20 minutes post-EP. Spontaneous contractions were observed after sublethal EP application but their frequency decreased progressively within 20 minutes. Lethal EP voltage threshold was lower in myocytes oriented perpendicular than parallel to the electric field using 100 µs pulses while an opposite effect was found using 10 ms pulses. Sublethal EP affected rat left ventricular myocytes contractility and disrupted Ca2+ homeostasis as a function of the EP voltage. Moreover, EP-induced lethality was preceded by a large increase in intracellular Ca2+ and was dependent upon the EP duration, amplitude and left ventricular myocytes orientation with respect to the electric field. These findings provide new insights into the effect of pulsed electric field on cardiac myocytes.

Substantially Improved Electrofusion Efficiency of Hybridoma Cells: Based on the Combination of Nanosecond and Microsecond Pulses.

As the initial antibody technology, the preparation of hybridoma cells has been widely used in discovering antibody drugs and is still in use. Various antibody drugs obtained through this technology have been approved for treating human diseases. However, the key to producing hybridoma cells is efficient cell fusion. High-voltage microsecond pulsed electric fields (μsHVPEFs) are currently one of the most common methods used for cell electrofusion. Nevertheless, the membrane potential induced by the external microsecond pulse is proportional to the diameter of the cell, making it difficult to fuse cells of different sizes. Although nanosecond pulsed electric fields (nsPEFs) can achieve the fusion of cells of different sizes, due to the limitation of pore size, deoxyribonucleic acid (DNA) cannot efficiently pass through the cell pores produced by nsPEFs. This directly causes the significant loss of the target gene and reduces the proportion of positive cells after fusion. To achieve an electric field environment independent of cell size and enable efficient cell fusion, we propose a combination of nanosecond pulsed electric fields and low-voltage microsecond pulsed electric fields (ns/μsLVPEFs) to balance the advantages and disadvantages of the two techniques. The results of fluorescence experiments and hybridoma culture experiments showed that after lymphocytes and myeloma cells were stimulated by a pulse (ns/μsLVPEF, μsHVPEF, and control), compared with μsHVPEF, applying ns/μsLVPEF at the same energy could increase the cell fusion efficiency by 1.5–3.0 times. Thus far, we have combined nanosecond and microsecond pulses and provided a practical solution that can significantly increase cell fusion efficiency. This efficient cell fusion method may contribute to the further development of hybridoma technology in electrofusion.

High Voltage Pulsed Electric Field Technology to Kill Bacteria or Pathogens in Sewage

High Voltage Pulsed Electric Field Technology to Kill Bacteria or Pathogens in Sewage