As the need for antibody production rises, there is an urgent need to lower the costs and enhance the efficiency of the separation process. Currently, the chromatographic media used for antibody separation and purification often focus on individual properties of antibodies, such as affinity, hydrophobicity, and charge, leading to issues like low purification efficiency or inadequate adsorption capacity. To address this, an electrostatically coupled polypeptide affinity medium (FD7-3, 5-diaminobenzoic acid n-sepharose, FD7-DA-Sepharose) was developed for rapid purification of antibodies from cell culture supernatant. This medium utilized 3, 5-diaminobenzoic acid as a spacer to attach the heptapeptide-affinity ligand (FYEILHD, FD7) to agarose microspheres. Antibodies could be adsorbed through charge interactions with the carboxyl functional group of the FD7-DA-Sepharose spacer, while FD7 enhanced electrostatic coupling and affinity adsorption through synergistic effects, significantly increasing the adsorption capacity while maintaining the affinity and specificity. The influences of pH and ionic strength on adsorption capacity were investigated with human immunoglobulin as a model protein. The static adsorption capacity (Q_m) of FD7-DA-Sepharose in the solution of pH 6.0 reached 67.73 mg/mL, representing a 52.68% increase compared with that (44.36 mg/mL) of the commercial Protein A affinity medium. Furthermore, the elution conditions for FD7-DA- Sepharose were mild (20 mmol/L PB, 0.5 mol/L NaCl, pH 6.0), in contrast to the harsh acidic elution (pH 2.7-3.6) typically associated with Protein A, which can damage antibody integrity. The FD7-DA-Sepharose medium was then employed to purify antibodies from cell culture supernatant, achieving the yield of 94.8% and the purity of 98.4%. The secondary structure of the purified antibody was determined by circular dichroism spectroscopy. The results demonstrated that FD7-DA-Sepharose enabled efficient purification of antibodies from cell culture supernatant, which provided a cost-effective solution (approximately one-third the price of commercial Protein A affinity medium) with gentle elution conditions that preserve the natural conformation of antibodies. This approach paves a novel, economical, and efficient way for the separation and purification of antibodies from cell culture supernatant.
Chromatography, Affinity/methods* ; Static Electricity ; Humans ; Sepharose/analogs & derivatives* ; Peptides/chemistry* ; Adsorption ; Antibodies/isolation & purification*

Magneto-acoustic-electric tomography (MAET) boasts high resolution in ultrasound imaging and high contrast in electrical impedance imaging, making it of significant research value in the fields of early tumor diagnosis and bioelectrical monitoring. In this study, a method was proposed that combined high conductivity liquid metal and maximum length sequence (M sequence) coded excitation to improve the signal-to-noise ratio. It was shown that, under rotational scanning, the liquid metal significantly improved the signal-to-noise ratio of the inter-tissue magneto-acoustic-electric signal and enhanced the quality of the reconstructed image. The signal-to-noise ratio of the signal was increased by 5.6, 11.1, 21.7, and 45.7 times under the excitation of 7-, 15-, 31-, and 63-bit M sequence code, respectively. The total usage time of 31-bit M sequence coded excitation imaging was shortened by 75.6% compared with single-pulse excitation when the same signal-to-noise ratio was improved. In conclusion, the imaging method combining liquid metal and M-sequence coding excitation has positive significance for improving MAET image quality.
Contrast Media ; Electricity ; Electric Conductivity ; Acoustics ; Tomography

In transcranial magnetic stimulation (TMS), the conductivity of brain tissue is obtained by using diffusion tensor imaging (DTI) data processing. However, the specific impact of different processing methods on the induced electric field in the tissue has not been thoroughly studied. In this paper, we first used magnetic resonance image (MRI) data to create a three-dimensional head model, and then estimated the conductivity of gray matter (GM) and white matter (WM) using four conductivity models, namely scalar (SC), direct mapping (DM), volume normalization (VN) and average conductivity (MC), respectively. Isotropic empirical conductivity values were used for the conductivity of other tissues such as the scalp, skull, and cerebrospinal fluid (CSF), and then the TMS simulations were performed when the coil was parallel and perpendicular to the gyrus of the target. When the coil was perpendicular to the gyrus where the target was located, it was easy to get the maximum electric field in the head model. The maximum electric field in the DM model was 45.66% higher than that in the SC model. The results showed that the conductivity component along the electric field direction of which conductivity model was smaller in TMS, the induced electric field in the corresponding domain corresponding to the conductivity model was larger. This study has guiding significance for TMS precise stimulation.
Transcranial Magnetic Stimulation ; Diffusion Tensor Imaging ; Electric Conductivity ; Electricity ; Scalp

As a new energy source for atrial fibrillation ablation, electric pulse ablation has higher tissue selectivity and biosafety, so it has a great application prospect. At present, there is very limited research on multi-electrode simulated ablation of histological electrical pulse. In this study, a circular multi-electrode ablation model of pulmonary vein will be built on COMSOL5.5 platform for simulation research. The results show that when the voltage amplitude reaches about 900 V, it can make some positions achieve transmural ablation, and the depth of continuous ablation area formed can reach 3 mm when the voltage amplitude reaches 1 200 V. When the distance between catheter electrode and myocardial tissue is increased to 2 mm, a voltage of at least 2 000 V is required to make the depth of continuous ablation area reach 3 mm. Through the simulation of electric pulse ablation with ring electrode, the research results of this project can provide reference for the voltage selection in the clinical application of electric pulse ablation.
Humans ; Heart Rate ; Atrial Fibrillation/surgery* ; Electrodes ; Catheter Ablation ; Electricity

Synthetic electroactive microbial consortia, which include exoelectrogenic and electrotrophic communities, catalyze the exchange of chemical and electrical energy in cascade metabolic reactions among different microbial strains. In comparison to a single strain, a community-based organisation that assigns tasks to multiple strains enables a broader feedstock spectrum, faster bi-directional electron transfer, and greater robustness. Therefore, the electroactive microbial consortia held great promise for a variety of applications such as bioelectricity and biohydrogen production, wastewater treatment, bioremediation, carbon and nitrogen fixation, and synthesis of biofuels, inorganic nanomaterials, and polymers. This review firstly summarized the mechanisms of biotic-abiotic interfacial electron transfer as well as biotic-biotic interspecific electron transfer in synthetic electroactive microbial consortia. This was followed by introducing the network of substance and energy metabolism in a synthetic electroactive microbial consortia designed by using the "division-of-labor" principle. Then, the strategies for engineering synthetic electroactive microbial consortiums were explored, which included intercellular communications optimization and ecological niche optimization. We further discussed the specific applications of synthetic electroactive microbial consortia. For instance, the synthetic exoelectrogenic communities were applied to biomass generation power technology, biophotovoltaics for the generation of renewable energy and the fixation of CO₂. Moreover, the synthetic electrotrophic communities were applied to light-driven N₂ fixation. Finally, this review prospected future research of the synthetic electroactive microbial consortia.
Microbial Consortia ; Synthetic Biology ; Electron Transport ; Electricity ; Biodegradation, Environmental

Existing neuroregulatory techniques can achieve precise stimulation of the whole brain or cortex, but high-focus deep brain stimulation has been a technical bottleneck in this field. In this paper, based on the theory of negative permeability emerged in recent years, a simulation model of magnetic replicator is established to study the distribution of the induced electric field in the deep brain and explore the possibility of deep focusing, which is compared with the traditional magnetic stimulation method. Simulation results show that a single magnetic replicator realized remote magnetic source. Under the condition of the same position and compared with the traditional method of stimulating, the former generated smaller induced electric field which sharply reduced with distance. By superposition of the magnetic field replicator, the induced electric field intensity could be increased and the focus could be improved, reducing the number of peripheral wires while guaranteeing good focus. The magnetic replicator model established in this paper provides a new idea for precise deep brain stimulation, which can be combined with neuroregulatory techniques in the future to lay a foundation for clinical application.
Brain ; Cerebral Cortex ; Computer Simulation ; Electricity ; Magnetic Fields

Power supply plays a key role in ensuring animal robots to obtain effective stimulation. To extending the stimulating time, there is a need to apply photovoltaic cells and monitor their parameter variations, which can help operators to obtain the optimal stimulation strategy. In this paper, an online monitoring system of photovoltaic cells for animal robot stimulators was presented. It was composed of battery information sampling circuit, multi-channel neural signal generator, power module and human-computer interaction interface. When the signal generator was working, remote navigation control of animal robot could be achieved, and the battery voltage, current, temperature and electricity information was collected through the battery information sampling circuit and displayed on the human-computer interaction system in real time. If there was any abnormal status, alarm would be activated. The battery parameters were obtained by charging and discharging test. The battery life under different light intensity and the stimulation effect of neural signal generator were tested. Results showed that the sampling errors of battery voltage, current and electric quantity were less than 15 mV, 5 mA and 6 mAh, respectively. Compared with the system without photovoltaic cells, the battery life was extended by 148% at the light intensity of 78 320 lx, solving the battery life problem to some extent. When animal robot was stimulated with this system, left and right turns could be controlled to complete with the success rate more than 80%. It will help researchers to optimize animal robot control strategies through the parameters obtained in this system.
Animals ; Humans ; Robotics ; Electric Power Supplies ; Electricity ; User-Computer Interface

Objective: To investigate the regulatory effects of bio-intensity electric field on the transformation of human skin fibroblasts (HSFs). Methods: The experimental research methods were used. HSFs were collected and divided into 200 mV/mm electric field group treated with 200 mV/mm electric field for 6 h and simulated electric field group placed in the electric field device without electricity for 6 h. Changes in morphology and arrangement of cells were observed in the living cell workstation; the number of cells at 0 and 6 h of treatment was recorded, and the rate of change in cell number was calculated; the direction of cell movement, movement velocity, and trajectory velocity within 3 h were observed and calculated (the number of samples was 34 in the simulated electric field group and 30 in 200 mV/mm electric field group in the aforementioned experiments); the protein expression of α-smooth muscle actin (α-SMA) in cells after 3 h of treatment was detected by immunofluorescence method (the number of sample was 3). HSFs were collected and divided into simulated electric field group placed in the electric field device without electricity for 3 h, and 100 mV/mm electric field group, 200 mV/mm electric field group, and 400 mV/mm electric field group which were treated with electric fields of corresponding intensities for 3 h. Besides, HSFs were divided into simulated electric field group placed in the electric field device without electricity for 6 h, and electric field treatment 1 h group, electric field treatment 3 h group, and electric field treatment 6 h group treated with 200 mV/mm electric field for corresponding time. The protein expressions of α-SMA and proliferating cell nuclear antigen (PCNA) were detected by Western blotting (the number of sample was 3). Data were statistically analyzed with Mann-Whitney U test, one-way analysis of variance, independent sample t test, and least significant difference test. Results: After 6 h of treatment, compared with that in simulated electric field group, the cells in 200 mV/mm electric field group were elongated in shape and locally adhered; the cells in simulated electric field group were randomly arranged, while the cells in 200 mV/mm electric field group were arranged in a regular longitudinal direction; the change rates in the number of cells in the two groups were similar (P>0.05). Within 3 h of treatment, the cells in 200 mV/mm electric field group had an obvious tendency to move toward the positive electrode, and the cells in simulated electric field group moved around the origin; compared with those in simulated electric field group, the movement velocity and trajectory velocity of the cells in 200 mV/mm electric field group were increased significantly (with Z values of -5.33 and -5.41, respectively, P<0.01), and the directionality was significantly enhanced (Z=-4.39, P<0.01). After 3 h of treatment, the protein expression of α-SMA of cells in 200 mV/mm electric field group was significantly higher than that in simulated electric field group (t=-9.81, P<0.01). After 3 h of treatment, the protein expressions of α-SMA of cells in 100 mV/mm electric field group, 200 mV/mm electric field group, and 400 mV/mm electric field group were 1.195±0.057, 1.606±0.041, and 1.616±0.039, respectively, which were significantly more than 0.649±0.028 in simulated electric field group (P<0.01). Compared with that in 100 mV/mm electric field group, the protein expressions of α-SMA of cells in 200 mV/mm electric field group and 400 mV/mm electric field group were significantly increased (P<0.01). The protein expressions of α-SMA of cells in electric field treatment 1 h group, electric field treatment 3 h group, and electric field treatment 6 h group were 0.730±0.032, 1.561±0.031, and 1.553±0.045, respectively, significantly more than 0.464±0.020 in simulated electric field group (P<0.01). Compared with that in electric field treatment 1 h group, the protein expressions of α-SMA in electric field treatment 3 h group and electric field treatment 6 h group were significantly increased (P<0.01). After 3 h of treatment, compared with that in simulated electric field group, the protein expressions of PCNA of cells in 100 mV/mm electric field group, 200 mV/mm electric field group, and 400 mV/mm electric field group were significantly decreased (P<0.05 or P<0.01); compared with that in 100 mV/mm electric field group, the protein expressions of PCNA of cells in 200 mV/mm electric field group and 400 mV/mm electric field group were significantly decreased (P<0.05 or P<0.01); compared with that in 200 mV/mm electric field group, the protein expression of PCNA of cells in 400 mV/mm electric field group was significantly decreased (P<0.01). Compared with that in simulated electric field group, the protein expressions of PCNA of cells in electric field treatment 1 h group, electric field treatment 3 h group, and electric field treatment 6 h group were significantly decreased (P<0.01); compared with that in electric field treatment 1 h group, the protein expressions of PCNA of cells in electric field treatment 3 h group and electric field treatment 6 h group were significantly decreased (P<0.05 or P<0.01); compared with that in electric field treatment 3 h group, the protein expression of PCNA of cells in electric field treatment 6 h group was significantly decreased (P<0.01). Conclusions: The bio-intensity electric field can induce the migration of HSFs and promote the transformation of fibroblasts to myofibroblasts, and the transformation displays certain dependence on the time and intensity of electric field.
Actins/biosynthesis* ; Cell Differentiation/physiology* ; Cell Movement/physiology* ; Electric Stimulation Therapy ; Electricity ; Fibroblasts/physiology* ; Humans ; Myofibroblasts/physiology* ; Proliferating Cell Nuclear Antigen/biosynthesis* ; Skin/cytology*

Objective: To investigate the regulatory effects of bio-intensity electric field on directional migration and microtubule acetylation in human epidermal cell line HaCaT, aiming to provide molecular theoretical basis for the clinical treatment of wound repair. Methods: The experimental research methods were used. HaCaT cells were collected and divided into simulated electric field group (n=54) placed in the electric field device without electricity for 3 h and electric field treatment group (n=52) treated with 200 mV/mm electric field for 3 h (the same treatment methods below). The cell movement direction was observed in the living cell workstation and the movement velocity, trajectory velocity, and direction of cosθ of cell movement within 3 h of treatment were calculated. HaCaT cells were divided into simulated electric field group and electric field treatment 1 h group, electric field treatment 2 h group, and electric field treatment 3 h group which were treated with 200 mV/mm electric field for corresponding time. HaCaT cells were divided into simulated electric field group and 100 mV/mm electric field group, 200 mV/mm electric field group, and 300 mV/mm electric field group treated with electric field of corresponding intensities for 3 h. The protein expression of acetylated α-tubulin was detected by Western blotting (n=3). HaCaT cells were divided into simulated electric field group and electric field treatment group, and the protein expression of acetylated α-tubulin was detected and located by immunofluorescence method (n=3). Data were statistically analyzed with Kruskal-Wallis H test,Mann-Whitney U test, Bonferroni correction, one-way analysis of variance, least significant difference test, and independent sample t test. Results: Within 3 h of treatment, compared with that in simulated electric field group, the cells in electric field treatment group had obvious tendency to move directionally, the movement velocity and trajectory velocity were increased significantly (with Z values of -8.53 and -2.05, respectively, P<0.05 or P<0.01), and the directionality was significantly enhanced (Z=-8.65, P<0.01). Compared with (0.80±0.14) in simulated electric field group, the protein expressions of acetylated α-tubulin in electric field treatment 1 h group (1.50±0.08) and electric field treatment 2 h group (1.89±0.06) were not changed obviously (P>0.05), while the protein expression of acetylated α-tubulin of cells in electric field treatment 3 h group (3.37±0.36) was increased significantly (Z=-3.06, P<0.05). After treatment for 3 h, the protein expressions of acetylated α-tubulin of cells in 100 mV/mm electric field group, 200 mV/mm electric field group, and 300 mV/mm electric field group were 1.63±0.05, 2.24±0.08, and 2.00±0.13, respectively, which were significantly more than 0.95±0.27 in simulated electric field group (P<0.01). Compared with that in 100 mV/mm electric field group, the protein expressions of acetylated α-tubulin in 200 mV/mm electric field group and 300 mV/mm electric field group were increased significantly (P<0.01); the protein expression of acetylated α-tubulin of cells in 300 mV/mm electric field group was significantly lower than that in 200 mV/mm electric field group (P<0.05). After treatment for 3 h, compared with that in simulated electric field group, the acetylated α-tubulin of cells had enhanced directional distribution and higher protein expression (t=5.78, P<0.01). Conclusions: Bio-intensity electric field can induce the directional migration of HaCaT cells and obviously up-regulate the level of α-ubulin acetylation after treatment at 200 mV/mm bio-intensity electric field for 3 h.
Humans ; Acetylation ; Tubulin/metabolism* ; Microtubules/metabolism* ; Electricity ; Epidermal Cells/metabolism*

The international cooperation project "electricity-driven low energy and chemical input technology for accelerated bioremediation" (abridged as "ELECTRA") is jointly supported by National Nature Science Foundation of China (NSFC) and European Commission (EC). The ELECTRA consortium consists of 5 research institutions and universities from China and 17 European research institutions and universities, as well as high-tech companies of EC countries. ELECTRA focuses on researches of biodegradation of emerging organic compounds (EOCs) and novel environmental biotechnologies of low-energy and low-chemical inputs. The project has been successfully operated for 2 years, and has made important progresses in obtaining EOCs-degrading microbes, developing weak-electricity-accelerated bioremediation, and 3D-printing techniques for microbial consortium. The ELECTRA has promoted collaborations among the Chinese and European scientists. In the future, ELECTRA will overcome the negative impact of the COVID-19 pandemic and fulfill the scientific objectives through strengthening the international collaboration.
Biodegradation, Environmental ; Biotechnology ; COVID-19 ; Electricity ; Humans ; Pandemics ; SARS-CoV-2