34 results on '"Mengxi, M."'
Search Results
2. Sulfur-tetrazine as highly efficient visible-light activatable photo-trigger for designing photoactivatable fluorescence biomolecules.
- Author
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Yang S, Zhang M, Loredo A, Soares D, Wu Y, and Xiao H
- Subjects
- Photochemical Processes, Humans, Heterocyclic Compounds, 1-Ring chemistry, Molecular Structure, Light, Sulfur chemistry, Fluorescent Dyes chemistry
- Abstract
Light-activated fluorescence represents a potent tool for investigating subcellular structures and dynamics, offering enhanced control over the temporal and spatial aspects of the fluorescence signal. While alkyl-substituted tetrazine has previously been reported as a photo-trigger for various fluorophore scaffolds, its limited photochemical efficiency and high activation energy have constrained its widespread application at the biomolecular level. In this study, we demonstrate that a single sulfur atom substitution of tetrazine greatly enhances the photochemical properties of tetrazine conjugates and significantly improves their photocleavage efficiency. Notably, the resulting sulfur-tetrazine can be activated using a lower-energy light source, thus transforming it into a valuable visible-light photo-trigger. To introduce this photo-trigger into biological systems, we have developed a series of visible-light activatable small molecular dyes, along with a photoactivatable noncanonical amino acid containing sulfur-tetrazine. Using the Genetic Code Expansion technology, this novel amino acid is genetically incorporated into fluorescent protein molecules, serving as a phototrigger to create an innovative photoactivatable protein. These advancements in tetrazine-scaffold photo-trigger design open up new avenues for generating photoactivatable biomolecules, promising to greatly facilitate the exploration of biological functions and structures.
- Published
- 2024
- Full Text
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3. Lacticaseibacillus casei - and Bifidobacterium breve -fermented red pitaya promotes beneficial microbial proliferation in the colon.
- Author
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Cao L, Wan M, Xian Z, Zhou Y, Dong L, Huang F, and Su D
- Subjects
- Humans, Gastrointestinal Microbiome, Male, alpha-Amylases metabolism, alpha-Glucosidases metabolism, Glycoside Hydrolase Inhibitors pharmacology, Lacticaseibacillus casei metabolism, Fermentation, Probiotics, Bifidobacterium breve, Colon microbiology, Colon metabolism
- Abstract
Red pitaya has been demonstrated to strongly inhibit α-glucosidase activity; however, the impact of red pitaya fermentation by probiotic bacteria on α-glucosidase inhibition remains unclear. In this study, six strains of lactic acid bacteria ( Lactiplantibacillus plantarum , Lacticaseibacillus rhamnosus , Lactobacillus bulgaricus , Lacticaseibacillus casei , Lactobacillus acidophilus and Streptococcus thermophilus ) and one strain of Bifidobacterium breve were utilized for the fermentation of red pitaya pulp. The α-glucosidase and α-amylase inhibition rates of red pitaya pulp were significantly greater after fermentation by Bifidobacterium breve and Lacticaseibacillus casei than by the other abovementioned strains. The LC group exhibited an α-glucosidase inhibition rate of 99%, with an α-amylase inhibition rate of 89.91%. In contrast, the BB group exhibited an α-glucosidase inhibition rate of 95.28%, accompanied by an α-amylase inhibition rate of 95.28%. Moreover, red pitaya pulp fermented with Bifidobacterium breve and Lacticaseibacillus casei produced a notable quantity of oligosaccharides, which was more than three times greater than that in the other groups. Furthermore, 16S rRNA high-throughput sequencing analysis was conducted to assess alterations in the composition of the gut microbiota. This revealed an increase in the abundance of Lactobacillus and Faecalibacterium in the pulp fermented by Bifidobacterium breve and Lacticaseibacillus casei , whereas the abundance of Sutterella decreased. Further analysis at the species level revealed that Bifidobacterium longum , Faecalibacterium prausnitzii , and Lactobacillus zeae were the dominant strains present during colonic fermentation. These results indicate a beneficial health trend associated with probiotic bacterial fermentation of red pitaya pulp, which is highly important for the development of functional products.
- Published
- 2024
- Full Text
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4. A fluorinated metal-organic framework-based quasi-solid electrolyte for stabilizing Li metal anodes.
- Author
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Wang X, Bai M, Li Q, Li J, Li D, Lin X, Shao S, and Wang Z
- Abstract
A fluorinated quasi-solid electrolyte (QSE) with a high conductivity of 2.3 mS cm
-1 is meticulously designed for Li metal batteries. It facilitates the formation of a LiF-rich solid electrolyte interface that effectively enhances the reversibility of Li anodes. The assembled Li|QSE|LiFePO4 batteries exhibit 92.3% capacity retention after 1500 cycles and an impressive capacity of up to 45 mA h g-1 at 20C.- Published
- 2024
- Full Text
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5. Acoustofluidic-based microscopic examination for automated and point-of-care urinalysis.
- Author
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He X, Ren F, Wang Y, Zhang Z, Zhou J, Huang J, Cao S, Dong J, Wang R, Wu M, and Liu J
- Subjects
- Humans, Microscopy instrumentation, Microfluidic Analytical Techniques instrumentation, Lab-On-A-Chip Devices, Erythrocytes cytology, Automation, Leukocytes cytology, Acoustics instrumentation, Equipment Design, Urinalysis instrumentation, Point-of-Care Systems
- Abstract
Urinalysis is a heavily used diagnostic test in clinical laboratories; however, it is chronically held back by urine sediment microscopic examination. Current instruments are bulky and expensive to be widely adopted, making microscopic examination a procedure that still relies on manual operations and requires large time and labor costs. To improve the efficacy and automation of urinalysis, this study develops an acoustofluidic-based microscopic examination system. The system utilizes the combination of acoustofluidic manipulation and a passive hydrodynamic mechanism, and thus achieves a high throughput (1000 μL min
-1 ) and a high concentration factor (95.2 ± 2.1 fold) simultaneously, fulfilling the demands for urine examination. The concentrated urine sample is automatically dispensed into a hemocytometer chamber and the images are then analyzed using a machine learning algorithm. The whole process is completed within 3 minutes with detection accuracies of erythrocytes and leukocytes of 94.6 ± 3.5% and 95.1 ± 1.8%, respectively. The examination outcome of urine samples from 50 volunteers by this device shows a correlation coefficient of 0.96 compared to manual microscopic examination. Our system offers a promising tool for automated urine microscopic examination, thus it has potential to save a large amount of time and labor in clinical laboratories, as well as to promote point-of-care urine testing applications in and beyond hospitals.- Published
- 2024
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6. A point-of-care testing platform for on-site identification of genetically modified crops.
- Author
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Wang Y, Yang F, Fu Y, He X, Tian H, Yang L, Wu M, Cao J, and Liu J
- Subjects
- Lab-On-A-Chip Devices, Nucleic Acid Amplification Techniques instrumentation, Microfluidic Analytical Techniques instrumentation, Plants, Genetically Modified genetics, Crops, Agricultural genetics, Point-of-Care Testing
- Abstract
Genetically modified (GM) food is still highly controversial nowadays. Due to the disparate policies and attitudes worldwide, demands for a rapid, cost-effective and user-friendly GM crop identification method are increasingly significant for import administration, market supervision, etc. However, as the most-recognized methods, nucleic acid-based identification approaches require bulky instruments, long turn-around times and trained personnel, which are only suitable in laboratories. To fulfil the urgent needs of on-site testing, we develop a point-of-care testing platform that is able to identify 12 types of GM crops in less than 40 minutes without using laboratory settings. Our system integrates sample pre-treatment modules in a microfluidic chip, performs DNA amplification via a battery-powered portable kit, and presents results via eye-recognized colorimetric change. A paraffin-based reflow method and a slip plate-based fluid switch are developed to encapsulate and release amplification primers in individual microwells on demand, thus enabling identification of varied targets simultaneously. Our system offers an efficient, affordable and convenient tool for GM crop identification, thus it will not only benefit customs and market administration bureaus, but also satisfy demands of numerous consumers.
- Published
- 2024
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7. Palladium-catalyzed enantioselective umpolung allylation of amido-tethered allylic carbonates with isatin-derived ketimines.
- Author
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Wang L, Lu M, Li K, Yang S, Wang L, and Guo H
- Abstract
A palladium-catalyzed enantioselective umpolung allylation reaction of amido-tethered allyl carbonates with N -2,2,2-trifluoroethylisatin ketimines has been realized herein. The reaction worked well under mild reaction conditions to give various chiral oxindole derivatives in moderate to excellent yields with high enantioselectivities. Notably, this work represents the first Pd-catalyzed asymmetric umpolung allylation reaction of N -2,2,2-trifluoroethylisatin ketimines.
- Published
- 2024
- Full Text
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8. Capping layer enabled controlled fragmentation of two-dimensional materials by cold drawing.
- Author
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Chen M, Li D, Hou Y, Gu M, Zeng Q, Ning, Li W, Zheng X, Shao Y, Wang Z, Xia J, Yang C, Wei L, and Gao H
- Abstract
Cold drawing, a well-established processing technique in the polymer industry, was recently revisited and discovered as an efficient material structuring method to create ordered patterns in composites consisting of both cold-drawable polymers and brittle target materials. Such a high-yield and low-cost manufacturing technique enables the large-scale fabrication of micro-ribbon structures for a wide range of functional materials, including two-dimensional (2D) layered materials. Compared to the abundant phenomenological results from experiments, however, the underlying mechanisms of this technique are not fully explored. Here, supported by experimental investigation, finite element calculations, and theoretical modeling, we systematically study the effect of a capping layer on the controlled fragmentation of 2D materials deposited on polymer substrates during the cold drawing. The capping layer is found to prevent the premature fracture of the 2D thin films during elastic deformation of the substrate, when a specific requirement proposed by the theoretical model is satisfied. Controlled fragmentation is enabled in the necking stage due to the protective effect of the capping layer, which also influences the size of the resulting fragments. Flexible and stretchable electrodes based on 2D material ribbons are fabricated to demonstrate the effectiveness of the proposed roadmap. This study gives an accurate understanding of interactions between 2D materials, polymer substrates, and capping layers during cold drawing, and offers guidance for potential applications such as flexible electronics.
- Published
- 2023
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9. Binuclear cobalt(II) and two-dimensional manganese(II) coordination compounds self-assembled by mixed bipyridine-tetracarboxylic ligands with single-ion magnet properties.
- Author
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Wu DQ, Kumari K, Wan Y, Gao X, Guo M, Liu G, Shao D, Zhai B, and Singh SK
- Abstract
A cobalt(II) complex and manganese(II) coordination polymer, formulated as [Co
2 (H2 btca)(mbpy)4 ][H2 btca]·4H2 O (1) and {Mn2 (btca)(mbpy)2 (H2 O)2 }n (2) (H4 btca = 1,2,4,5-benzenetetracarboxylic acid; mbpy = 4,4'-dimethyl-2,2'-bipyridyl), constructed by mixed bipyridine-tetracarboxylic ligands were synthesized and characterized. Single-crystal structural analyses reveal that compound 1 is a discrete neutral binuclear molecule, while compound 2 is a two-dimensional (2D) coordination polymer. The metal ions in these compounds are well isolated, with an intramolecular Co2+ ⋯Co2+ distance of 9.170 Å for 1 and Mn2+ ⋯Mn2+ separation of 10.984 and 11.164 Å for 2 due to the bulk tetracarboxylic linker. This isolation gives rise to a single-ion magnetism origin of the compounds. Magnetic studies reveal a large zero-field splitting parameter D of 82.6 cm-1 for 1, while a very small D of 0.42 cm-1 was observed for 2. Interestingly, dynamic ac magnetic measurements exhibited slow magnetic relaxation under the external dc field of the two compounds, revealing the field-supported single-ion magnet (SIM) of 1 and 2. The detailed theoretical calculations were further applied to understand the electronic structures, magnetic anisotropy, and relaxation dynamics in 1 and 2. Combined with our recently reported compound ( Eur. J. Inorg. Chem ., 2022, e202200354), the foregoing results provide not only a rare binuclear cobalt(II) SIM and the first 2D manganese(II) SIM coordination polymer but also a bipyridine-tetracarboxylic ligand approach toward novel SIMs.- Published
- 2023
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10. Occurrence, distribution and environmental risk of 19 anthelmintic drugs in river water and sediment from the Jinjiang River, China.
- Author
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Yang S, Liao M, Su S, Ding S, Li Y, and Gan Z
- Subjects
- Humans, Rivers, Environmental Monitoring, Water, China, Benzimidazoles, Risk Assessment, Geologic Sediments, Anthelmintics, Water Pollutants, Chemical analysis
- Abstract
This study explored the occurrence and distribution of 19 anthelmintic drugs (ADs) including the benzimidazole group, salicylanilide group, imidazothiazole group, tetrahydropyrimidine group, diphenylsulfide group, macrocyclic lactone group and hexahydropyrazine group in river water and sediment of the Jinjiang River in Sichuan, China, during summer and winter seasons. All targets were detected in river water (up to 74.64 ng L
-1 ) and sediment (up to 1701 ng g-1 ) samples. The predominant ADs were benzimidazoles regardless of seasons and matrices, accounting for 43-82% of the total anthelmintic abundance. Obvious seasonal variation of AD concentrations in the two matrices was observed, which could be attributed to the seasonality of human and veterinary uses of ADs. Evident spatial variation (urban and rural areas) of ADs in winter was indicative of the influence of anthropogenic activities on the environmental concentration of ADs. Though benzimidazoles accumulated in the water and sediment with the highest concentration among all the ADs, macrocyclic lactones were of the highest risk to non-target organisms through ecological risk assessment, with an RQEcotox value up to 2713. This work contributes to comprehensively assessing the contamination level, ecological level and transmission characteristics of ADs in the environment.- Published
- 2023
- Full Text
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11. Denitrification activity test of a V modified Mn-based ceramic filter.
- Author
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Sun L, Wang Z, and Zang M
- Abstract
In view of the characteristics of high temperature denitrification and low water and sulfur resistance of single manganese-based catalysts, a vanadium-manganese-based ceramic filter (VMA(14)-CCF) was prepared by the impregnation method modified with V. The results showed that the NO conversion of VMA(14)-CCF was more than 80% at 175-400 °C. At 225-300 °C, the conversion of NO can reach 100%. High NO conversion and low pressure drop can be maintained at all face velocities. The resistance of VMA(14)-CCF to water, sulfur and alkali metal poisoning is better than that of a single manganese-based ceramic filter. XRD, SEM, XPS and BET were further used for characterization analysis. The introduction of V protects the MnO
x center, promotes the conversion of Mn3+ to Mn4+ , and provides abundant surface adsorbed oxygen. The development of VMA(14)-CCF greatly broadens the application range of ceramic filters in denitrification., Competing Interests: The authors declared that they have no conflicts of interest to this work., (This journal is © The Royal Society of Chemistry.)- Published
- 2023
- Full Text
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12. Fluoride anion complexation and transport using a stibonium cation stabilized by an intramolecular PO → Sb pnictogen bond.
- Author
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Gonzalez VM, Park G, Yang M, and Gabbaï FP
- Abstract
We describe the synthesis of [ o -Ph
2 P(O)(C6 H4 )SbPh3 ]+ ([2]+ ), an intramolecularly base-stabilized stibonium Lewis acid which was obtained by reaction of [ o -Ph2 P(C6 H4 )SbPh3 ]+ with NOBF4 . This cation reacts with fluoride anions to afford the corresponding fluorostiborane o -Ph2 P(O)(C6 H4 )SbFPh3 , the structure of which indicates a strengthening of the PO → Sb interaction. When deployed in fluoride-containing POPC unilamellar vesicles, [2]+ behaves as a potent fluoride anion transporter whose activity greatly exceeds that of [Ph4 Sb]+ .- Published
- 2021
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13. Molecularly imprinted polymer coated Mn-doped ZnS quantum dots embedded in a metal-organic framework as a probe for selective room temperature phosphorescence detection of chlorpyrifos.
- Author
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Fan M, Gan T, Yin G, Cheng F, and Zhao N
- Abstract
As one of the most widely used organophosphorus pesticides, chlorpyrifos (CPF) is toxic to humans. However, the rapid, effective and sensitive detection of CPF is still a challenge. In this paper, a novel molecularly imprinted phosphorescent sensor with a core-shell structure (Mn:ZnS QDs@ZIF-8@MIP) using Mn:ZnS quantum dots (QDs) as phosphorescent emitters was prepared for the highly sensitive and selective detection of CPF, and a simple and rapid room-temperature phosphorescence (RTP) detection method for CPF was proposed. For the prepared Mn:ZnS QDs@ZIF-8@MIP, Mn:ZnS QDs had good phosphorescence emission characteristics, ZIF-8 as support materials was used to improve the dispersibility of Mn:ZnS QDs, and molecularly imprinted polymer (MIP) on the surface of ZIF-8 was used to improve the selectivity of Mn:ZnS QDs for CPF. Under the optimal response conditions, the RTP intensity of Mn:ZnS QDs@ZIF-8@MIP showed a rapid response to CPF (less than 5 min), the RTP intensity ratio of P
0 / P had a good linear relationship with the concentration of CPF in the range of 0-80 μM, and the detection limit of this method was 0.89 μM with the correlation coefficient of 0.99. Moreover, this simple and rapid method has been successfully used to detect CPF in real water samples with satisfactory results, and the recoveries ranged from 92% to 105% with a relative standard deviation of less than 1%. This method combines the advantages of phosphorescence emission and molecular imprinting, and greatly reduces the potential interferences of competitive substances, background fluorescence and scattered light, which opens up a broad prospect for the highly sensitive and selective detection of pollutants in water based on molecularly imprinted phosphorescent sensors., Competing Interests: The authors declare no competing interests., (This journal is © The Royal Society of Chemistry.)- Published
- 2021
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14. A Ganoderma atrum polysaccharide alleviated DSS-induced ulcerative colitis by protecting the apoptosis/autophagy-regulated physical barrier and the DC-related immune barrier.
- Author
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Zheng B, Ying M, Xie J, Chen Y, Wang Y, Ding X, Hong J, Liao W, and Yu Q
- Subjects
- Animals, Autophagy-Related Protein 5 metabolism, Beclin-1 metabolism, Caspase 3 metabolism, Caspase 9 metabolism, Colitis, Ulcerative chemically induced, Colon pathology, Interleukin-10 metabolism, Male, Mice, Mice, Inbred C57BL, Polysaccharides metabolism, Proto-Oncogene Proteins c-bcl-2 metabolism, Apoptosis drug effects, Autophagy drug effects, Autophagy-Related Protein 7 metabolism, Colitis, Ulcerative drug therapy, Ganoderma metabolism, Polysaccharides pharmacology, Protective Agents pharmacology
- Abstract
Polysaccharides are one of the main active substances in Ganoderma atrum (G. atrum). The purpose of this study was to explore the protective effect of a G. atrum polysaccharide (PSG-1) on DSS-induced colitis and the underlying mechanism. The results showed that PSG-1 could maintain the integrity of the intestinal structure by promoting the expression of goblet cells and levels of tight junction proteins in the colon of DSS-induced colitis mice. Furthermore, PSG-1 relieved the inhibition of Bcl-2 and the overexpression of caspase-3 and caspase-9 caused by DSS. Simultaneously, PSG-1 restored the expression of Atg5, Atg7 and beclin-1 and inhibited the p-akt and p-mTOR levels, suggesting that PSG-1 promoted autophagy via the Akt/mTOR pathway. Moreover, PSG-1 inhibited the content of DCs in the colon and modulated the expression of IL-10 in DCs. In conclusion, PSG-1 alleviated DSS-induced ulcerative colitis by protecting the apoptosis/autophagy-regulated physical barrier and the DC-related immune barrier.
- Published
- 2020
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15. Correction: High-throughput cell focusing and separation via acoustofluidic tweezers.
- Author
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Wu M, Chen K, Yang S, Wang Z, Huang PH, Mai J, Li ZY, and Huang TJ
- Abstract
Correction for 'High-throughput cell focusing and separation via acoustofluidic tweezers' by Mengxi Wu et al., Lab Chip, 2018, 18, 3003-3010, DOI: .
- Published
- 2020
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16. Correction: Separating extracellular vesicles and lipoproteins via acoustofluidics.
- Author
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Wu M, Chen C, Wang Z, Bachman H, Ouyang Y, Huang PH, Sadovsky Y, and Huang TJ
- Abstract
Correction for 'Separating extracellular vesicles and lipoproteins via acoustofluidics' by Mengxi Wu et al., Lab Chip, 2019, 19, 1174-1182, DOI: .
- Published
- 2020
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17. A disposable acoustofluidic chip for nano/microparticle separation using unidirectional acoustic transducers.
- Author
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Zhao S, Wu M, Yang S, Wu Y, Gu Y, Chen C, Ye J, Xie Z, Tian Z, Bachman H, Huang PH, Xia J, Zhang P, Zhang H, and Huang TJ
- Subjects
- Humans, Lab-On-A-Chip Devices, Transducers, Acoustics, Sound
- Abstract
Separation of nano/microparticles based on surface acoustic waves (SAWs) has shown great promise for biological, chemical, and medical applications ranging from sample purification to cancer diagnosis. However, the permanent bonding of a microchannel onto relatively expensive piezoelectric substrates and excitation transducers renders the SAW separation devices non-disposable. This limitation not only requires cumbersome cleaning and increased labor and material costs, but also leads to cross-contamination, preventing their implementation in many biological, chemical, and medical applications. Here, we demonstrate a high-performance, disposable acoustofluidic platform for nano/microparticle separation. Leveraging unidirectional interdigital transducers (IDTs), a hybrid channel design with hard/soft materials, and tilted-angle standing SAWs (taSSAWs), our disposable acoustofluidic devices achieve acoustic radiation forces comparable to those generated by existing permanently bonded, non-disposable devices. Our disposable devices can separate not only microparticles but also nanoparticles. Moreover, they can differentiate bacteria from human red blood cells (RBCs) with a purity of up to 96%. Altogether, we developed a unidirectional IDT-based, disposable acoustofluidic platform for micro/nanoparticle separation that can achieve high separation efficiency, versatility, and biocompatibility.
- Published
- 2020
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18. Facile morphology control of gold(0) structures from aurophilic assemblies.
- Author
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Aguiló E, Dalmases M, Lin M, Lima JC, Gavara R, Figuerola A, Llorca J, and Rodríguez L
- Abstract
Different gold microstructures have been synthesized by using supramolecular gold(i) organometallic compounds as templates and Ag nanoparticles as reducing agents. The use of fibers resulting from supramolecular assemblies of neutral gold(i) compounds gives rise to the formation of microrods. The use of supramolecular assemblies from ionic molecules results in spherical or square-based prism gold microstructures, depending on the shape of the supramolecular gold(i) precursor assembly. In addition to temperature and reaction time, solvents exert a strong influence on the formation and morphology of gold structures, as borne out by the example that well-defined star-like morphologies have been obtained in chloroform.
- Published
- 2020
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19. Phosphonium-stibonium and bis-stibonium cations as pnictogen-bonding catalysts for the transfer hydrogenation of quinolines.
- Author
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Yang M, Hirai M, and Gabbaï FP
- Subjects
- Borates chemistry, Catalysis, Cations, Hydrogenation, Molecular Structure, Phosphines chemistry, Stereoisomerism, Structure-Activity Relationship, Antimony chemistry, Benzene Derivatives chemistry, Lewis Acids chemistry, Organometallic Compounds chemistry, Organophosphorus Compounds chemistry, Quinolines chemistry
- Abstract
Bifunctional Lewis acidic group 15 compounds have emerged as appealing platforms for anion sensing and organocatalysis. As part of our interest in the chemistry of these compounds, we have now compared the catalytic properties of [o-(MePPh
2 )C6 H4 SbPh2 ]+ ([3]+ ), [o-(PPh2 )C6 H4 SbPh3 ]+ ([4]+ ), [o-(MePPh2 )C6 H4 SbPh3 ]2+ ([5]2+ ), and [o-C6 H4 (SbMePh2 )2 ]2+ ([6]2+ ) using the transfer hydrogenation of 2-phenyl-quinoline and 3-bromoquinoline with a Hantzsch ester benchmark reactions. This study, which also involved an evaluation of the catalytic properties of [Ph4 Sb]+ and [Ph3 MeP]+ , shows that antimony cations are generally more active than their phosphorus counterparts and neutral stiboranes. Our results also demonstrate that dicationic systems such as [6]2+ are superior activators.- Published
- 2019
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20. Separating extracellular vesicles and lipoproteins via acoustofluidics.
- Author
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Wu M, Chen C, Wang Z, Bachman H, Ouyang Y, Huang PH, Sadovsky Y, and Huang TJ
- Subjects
- Dimethylpolysiloxanes, Equipment Design, Humans, Nylons, Time Factors, Acoustics instrumentation, Extracellular Vesicles metabolism, Lab-On-A-Chip Devices, Lipoproteins isolation & purification
- Abstract
Extracellular vesicles (EVs) and lipoproteins are abundant and co-exist in blood. Both have been proven to be valuable as diagnostic biomarkers and for therapeutics. However, EVs and lipoproteins are both on the submicron scale and overlap in size distributions. Conventional methods to separate EVs and lipoproteins are inefficient and time-consuming. Here we present an acoustofluidic-based separation technique that is based on the acoustic property differences of EVs and lipoproteins. By using the acoustofluidic technology, EVs and subgroups of lipoproteins are separated in a label-free, contact-free, and continuous manner. With its ability for simple, rapid, efficient, continuous-flow isolation, our acoustofluidic technology could be a valuable tool for health monitoring, disease diagnosis, and personalized medicine.
- Published
- 2019
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21. Plastic-based acoustofluidic devices for high-throughput, biocompatible platelet separation.
- Author
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Gu Y, Chen C, Wang Z, Huang PH, Fu H, Wang L, Wu M, Chen Y, Gao T, Gong J, Kwun J, Arepally GM, and Huang TJ
- Subjects
- Cell Separation economics, Costs and Cost Analysis, Disposable Equipment, Equipment Design, Humans, Acoustics instrumentation, Blood Platelets cytology, Cell Separation instrumentation, Plastics
- Abstract
Platelet separation is a crucial step for both blood donation and treatment of essential thrombocytosis. Here we present an acoustofluidic device that is capable of performing high-throughput, biocompatible platelet separation using sound waves. The device is entirely made of plastic material, which renders the device disposable and more suitable for clinical use. We used this device to process undiluted human whole blood, and we demonstrate a sample throughput of 20 mL min-1, a platelet recovery rate of 87.3%, and a red/white blood cell removal rate of 88.9%. We preserved better platelet function and integrity for isolated platelets than those which are isolated using established methods. Our device features advantages such as rapid fabrication, high throughput, and biocompatibility, so it is a promising alternative to existing platelet separation approaches.
- Published
- 2019
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22. High-throughput cell focusing and separation via acoustofluidic tweezers.
- Author
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Wu M, Chen K, Yang S, Wang Z, Huang PH, Mai J, Li ZY, and Huang TJ
- Subjects
- Cell Line, Tumor, Erythrocytes cytology, Humans, Leukocytes cytology, Particle Size, Acoustics instrumentation, Cell Separation instrumentation, Lab-On-A-Chip Devices
- Abstract
Separation of particles and cells is an important function in many biological and biomedical protocols. Although a variety of microfluidic-based techniques have been developed so far, there is clearly still a demand for a precise, fast, and biocompatible method for separation of microparticles and cells. By combining acoustics and hydrodynamics, we have developed a method which we integrated into three-dimensional acoustofluidic tweezers (3D-AFT) to rapidly and efficiently separate microparticles and cells into multiple high-purity fractions. Compared with other acoustophoresis methods, this 3D-AFT method significantly increases the throughput by an order of magnitude, is label-free and gently handles the sorted cells. We demonstrate not only the separation of 10, 12, and 15 micron particles at a throughput up to 500 μl min-1 using this 3D-AFT method, but also the separation of erythrocytes, leukocytes, and cancer cells. This 3D-AFT method is able to meet various separation demands thus offering a viable alternative with potential for clinical applications.
- Published
- 2018
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23. Influence of the catalyst structure in the cycloaddition of isocyanates to oxiranes promoted by tetraarylstibonium cations.
- Author
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Yang M, Pati N, Bélanger-Chabot G, Hirai M, and Gabbaï FP
- Abstract
In the context of our work on electron deficient group 15 cations as Lewis acid catalysts, we have synthesized the triflate salts of a series of tetraarylstibonium cations of general formula [ArSbPh3]+ with Ar = Mes (4+), o-(dimethylamino)phenyl (5+), and o-((dimethylamino)methyl)phenyl (6+). These new cationic antimony derivatives, along with the known [Ph4Sb]+ (1+), 1-naphthyltriphenylstibonium (2+), and [(Ant)SbPh3]+ (3+), have been evaluated as catalysts for the cycloaddition of oxiranes and isocyanates under mild conditions. While all stibonium cations favor the 3,4-oxazolidinone products, the reactivities of 5+ and 6+ are hindered by the ancillary amino donor which quenches the Lewis acidity of the antimony center. A comparison of the other stibonium cations shows that 4+ is the most selective catalyst.
- Published
- 2018
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24. Rational design of sequestered DNAzyme beacons to enable flexible control of catalytic activities.
- Author
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Tang W, Cheng M, Dai D, Xiong Z, and Liu F
- Abstract
DNAzymes as functional units play increasingly important roles for DNA nanotechnology, and fine control of the catalytic activities of DNAzymes is a crucial element in the design and construction of functional and dynamic devices. So far, attempts to control cleavage kinetics can be mainly achieved through varying the concentrations of the specific metal ions. Here we present a facile sequestered DNAzyme beacon strategy based on precisely blocking the catalytic core of the DNAzyme, which can flexibly regulate the DNAzyme cleavage kinetics without changing the concentrations of metal ions. This strategy can be extended to couple with a large number of other RNA-cleaving DNAzymes and was successfully applied in designing a dual stem-loop structure probe for arbitrary sequence biosensing, which provides the possibility of scaling up versatile and dynamic DNA devices that use DNAzymes as functional modules., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)
- Published
- 2018
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25. On the coordination non-innocence of antimony in nickel(ii) complexes of the tetradentate (o-(Ph 2 P)C 6 H 4 ) 3 Sb ligand.
- Author
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Jones JS, Wade CR, Yang M, and Gabbaï FP
- Abstract
In a continuation of our investigations into the unusual properties of antimony-based ligands, we have decided to investigate the structure of the complexes formed by the tetradentate ligands (o-(Ph
2 P)C6 H4 )3 E (E = P (1), As (2), Sb (3)) with NiCl2 . We observed that the structure of the resulting complexes depends on the nature of the central pnictogen atom E, with the phosphorus- and arsenic-based systems adopting ionic structures of the type [ClNi(o-(Ph2 P)C6 H4 )3 E][Cl] (E = P ([4][Cl]), As ([5][Cl])) while the known antimony complex ClNi(o-(Ph2 P)C6 H4 )3 SbCl (6-Cl) is molecular, with a chloride anion bound to the antimony atom trans from the nickel atom. Using both structural and computational arguments, we propose that the Lewis acidic behavior of the antimony atom in the cation [ClNi(o-(Ph2 P)C6 H4 )3 Sb]+ ([6]+ ) which as been structurally characterized as its [BPh4 ]- salt, originates in part from the steric compression imposed by the rigid ligand buttresses and the larger size of antimony. This steric compression pushes the antimony atom of [6]+ toward a geometry that is closer to that of a trigonal-base pyramid, setting the stage for the coordination of a ligand trans from the nickel atom as in 6-Cl. Coordination of the chloride ligand also benefits from an accumulation of positive character at the antimony atom of [6]+ which is a assigned to the polarizable and electron-releasing nature of this heavy pnictogen.- Published
- 2017
- Full Text
- View/download PDF
26. Acoustofluidic coating of particles and cells.
- Author
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Ayan B, Ozcelik A, Bachman H, Tang SY, Xie Y, Wu M, Li P, and Huang TJ
- Subjects
- Equipment Design, HeLa Cells, Humans, Microspheres, Acoustics, Lab-On-A-Chip Devices
- Abstract
On-chip microparticle and cell coating technologies enable a myriad of applications in chemistry, engineering, and medicine. Current microfluidic coating technologies often rely on magnetic labeling and concurrent deflection of particles across laminar streams of chemicals. Herein, we introduce an acoustofluidic approach for microparticle and cell coating by implementing tilted-angle standing surface acoustic waves (taSSAWs) into microchannels with multiple inlets. The primary acoustic radiation force generated by the taSSAW field was exploited in order to migrate the particles across the microchannel through multiple laminar streams, which contained the buffer and coating chemicals. We demonstrate effective coating of polystyrene microparticles and HeLa cells without the need for magnetic labelling. We characterized the coated particles and HeLa cells with fluorescence microscopy and scanning electron microscopy. Our acoustofluidic-based particle and cell coating method is label-free, biocompatible, and simple. It can be useful in the on-chip manufacturing of many functional particles and cells.
- Published
- 2016
- Full Text
- View/download PDF
27. Insight into the effects of modifying π-bridges on the performance of dye-sensitized solar cells containing triphenylamine dyes.
- Author
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Chen S, Jia H, Zheng M, Shen K, and Zheng H
- Abstract
Herein we prepare four novel D-π-A dyes based on triphenylamine (ZHG1, ZHG2, ZHG3 and ZHG4) by modifying the π-bridges. Compared with ZHG1, the power conversion efficiency (PCE) of ZHG2 is improved to 6.1% after the introduction of ethynyl. But further extension of the conjugation of the π-bridges by introducing the chromophore 4,8-bis(n-octyloxy)-benzo[1,2-b:4,5-b']dithiophene (BDT) into ZHG3 conversely decreases the PCE to 4.6%. Improving the coplanarity by replacing cyclobenzene with thiophene in ZHG4 after introducing BDT further decreases the PCE of ZHG4 to 4.3%. Theoretical calculations indicate that the LUMOs of ZHG3 and ZHG4 were mainly delocalized over benzothiadiazole which is far from the anchoring groups. Cyclic voltammetry experiments indicate that the LUMO energy levels of ZHG3 and ZHG4 are lower than those of ZHG1 and ZHG2. Both of these results affect the ability to inject electrons into the TiO
2 conduction band. X-ray photoelectron spectroscopy (XPS) analysis shows that the mean thickness of the dye coverage for ZHG1, ZHG2, ZHG3 and ZHG4 is 16 Å, 18 Å, 27 Å and 24 Å, respectively. So the tilt angle of the dye backbone anchored on the TiO2 film is in the order of ZHG1 > ZHG2 > ZHG4 > ZHG3, which is consistent with the dye coverage of the outermost TiO2 surfaces. This result indicates that the intermolecular π-π aggregation in ZHG3 and ZHG4 with overlong π-bridges is more serious compared with that in ZHG1 and ZHG2. Perhaps the above two factors are the reason that the PCEs of ZHG3 and ZHG4 are lower than those of ZHG1 and ZHG2. So it is very important to find a balance point between the electron injection ability, intermolecular π-π aggregation and the expansion of the light absorption range.- Published
- 2016
- Full Text
- View/download PDF
28. High-throughput acoustic separation of platelets from whole blood.
- Author
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Chen Y, Wu M, Ren L, Liu J, Whitley PH, Wang L, and Huang TJ
- Subjects
- Humans, Acoustics, Blood Platelets cytology, Cell Separation methods
- Abstract
Platelets contain growth factors which are important in biomedical and clinical applications. In this work, we present an acoustic separation device for high-throughput, non-invasive platelet isolation. In particular, we separated platelets from whole blood at a 10 mL min(-1) throughput, which is three orders of magnitude greater than that of existing acoustic-based platelet separation techniques. Without sample dilution, we observed more than 80% RBC/WBC removal and platelet recovery. High throughput, high separation efficiency, and biocompatibility make this device useful for many clinical applications.
- Published
- 2016
- Full Text
- View/download PDF
29. Rapid formation of size-controllable multicellular spheroids via 3D acoustic tweezers.
- Author
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Chen K, Wu M, Guo F, Li P, Chan CY, Mao Z, Li S, Ren L, Zhang R, and Huang TJ
- Subjects
- Cell Culture Techniques methods, Drug Screening Assays, Antitumor instrumentation, Fluorouracil pharmacology, Hep G2 Cells, Humans, Lab-On-A-Chip Devices, Acoustics instrumentation, Cell Culture Techniques instrumentation, Drug Screening Assays, Antitumor methods, Equipment Design methods, Spheroids, Cellular cytology
- Abstract
The multicellular spheroid is an important 3D cell culture model for drug screening, tissue engineering, and fundamental biological research. Although several spheroid formation methods have been reported, the field still lacks high-throughput and simple fabrication methods to accelerate its adoption in drug development industry. Surface acoustic wave (SAW) based cell manipulation methods, which are known to be non-invasive, flexible, and high-throughput, have not been successfully developed for fabricating 3D cell assemblies or spheroids, due to the limited understanding on SAW-based vertical levitation. In this work, we demonstrated the capability of fabricating multicellular spheroids in the 3D acoustic tweezers platform. Our method used drag force from microstreaming to levitate cells in the vertical direction, and used radiation force from Gor'kov potential to aggregate cells in the horizontal plane. After optimizing the device geometry and input power, we demonstrated the rapid and high-throughput nature of our method by continuously fabricating more than 150 size-controllable spheroids and transferring them to Petri dishes every 30 minutes. The spheroids fabricated by our 3D acoustic tweezers can be cultured for a week with good cell viability. We further demonstrated that spheroids fabricated by this method could be used for drug testing. Unlike the 2D monolayer model, HepG2 spheroids fabricated by the 3D acoustic tweezers manifested distinct drug resistance, which matched existing reports. The 3D acoustic tweezers based method can serve as a novel bio-manufacturing tool to fabricate complex 3D cell assembles for biological research, tissue engineering, and drug development.
- Published
- 2016
- Full Text
- View/download PDF
30. Macrocyclic Se4N2[7,7]ferrocenophane and Se2N[10]ferrocenophane containing benzyl unit: synthesis, complexation, crystal structures, electrochemical and optical properties.
- Author
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Qu J, Song Y, Ji W, Jing S, Zhu D, Huang W, Zheng M, Li Y, and Ma J
- Abstract
Two novel macrocyclic polyselena[n]ferrocenophanes containing a pendent benzyl unit, 20-membered Se4N2[7,7]ferrocenophane (L1) and 10-membered Se2N[10]ferrocenophane (L2), were designed and synthesized. The reaction of L1 with two molar amounts of metal salts (M = Cu(+), Cu(2+), Pd(2+) and Hg(2+)) led to six dimetallic complexes 1-6. A crystallographic study revealed that each metal center in 1-5 was tetracoordinated to two selenium atoms from different ferrocene units, one aliphatic nitrogen atom and one co-ligand. The structures of the complexes contain a two-fold axis perpendicular to the molecular plane with two pendant benzyl moieties in an anti-conformation. Macrocycle L1 gives significant electrochemical, linear and third-order nonlinear optical responses to Cu(2+) and Hg(2+). The DFT/B3LYP calculations of 4 demonstrated a small HOMO-LUMO energy gap and delocalization of the π-electron cloud in the frontier molecular orbitals, which led to the enhancement of molecular NLO properties after complexation. The results show that the oxidation state of the ferrocene unit is accompanied by significant differences in the corresponding absorption spectra and third-order NLO properties.
- Published
- 2016
- Full Text
- View/download PDF
31. Simultaneous imaging of intracellular pH and O 2 using functionalized semiconducting polymer dots.
- Author
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Xu W, Lu S, Xu M, Jiang Y, Wang Y, and Chen X
- Abstract
We developed novel functionalized semiconducting polymer dots (Pdots) for the simultaneous imaging of intracellular pH and oxygen. The Pdots comprised a semiconducting polymer of poly[9,9-dioctylfluorenyl-2,7-diyl] (PFO), amino terminated polystyrene, fluorescein isothiocyanate (FITC) as a pH sensitive dye, and Pt(ii) meso-tetra(pentafluorophenyl)porphine (PtTFPP) as an oxygen sensitive dye. In the sensing Pdots, PFO was used as a donor for Förster resonance energy transfer. The emission wavelengths of the PFO, FITC and PtTFPP matched the three color channel of the red, green and blue chip, which offered great advantage for dual sensing using conventional fluorescence microscopy. The nanosensor was taken up by cells via endocytosis, and exhibited high brightness, small particle size, triple color under a single excitation, a large two-photon absorbance cross-section and low-toxicity to cells. These salient features demonstrated the potential utility of the Pdots for dual pH and O
2 imaging in cells.- Published
- 2016
- Full Text
- View/download PDF
32. Reusable acoustic tweezers for disposable devices.
- Author
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Guo F, Xie Y, Li S, Lata J, Ren L, Mao Z, Ren B, Wu M, Ozcelik A, and Huang TJ
- Subjects
- Equipment Design, Glass chemistry, HeLa Cells, Humans, Micromanipulation economics, Point-of-Care Systems economics, Sound, Acoustics instrumentation, Dimethylpolysiloxanes chemistry, Lab-On-A-Chip Devices economics, Micromanipulation instrumentation
- Abstract
We demonstrate acoustic tweezers used for disposable devices. Rather than forming an acoustic resonance, we locally transmitted standing surface acoustic waves into a removable, independent polydimethylsiloxane (PDMS)-glass hybridized microfluidic superstrate device for micromanipulation. By configuring and regulating the displacement nodes on a piezoelectric substrate, cells and particles were effectively patterned and transported into said superstrate, accordingly. With the label-free and contactless nature of acoustic waves, the presented technology could offer a simple, accurate, low-cost, biocompatible, and disposable method for applications in the fields of point-of-care diagnostics and fundamental biomedical studies.
- Published
- 2015
- Full Text
- View/download PDF
33. Preparation and antibacterial activities of polyaniline/Cu0.05Zn0.95O nanocomposites.
- Author
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Liang X, Sun M, Li L, Qiao R, Chen K, Xiao Q, and Xu F
- Subjects
- Aniline Compounds pharmacology, Aniline Compounds radiation effects, Anti-Bacterial Agents pharmacology, Anti-Bacterial Agents radiation effects, Candida albicans drug effects, Candida albicans growth & development, Catalysis, Copper pharmacology, Copper radiation effects, Escherichia coli drug effects, Escherichia coli growth & development, Microbial Sensitivity Tests, Microscopy, Electron, Scanning, Microscopy, Electron, Transmission, Nanocomposites radiation effects, Nanocomposites ultrastructure, Photochemical Processes, Spectrophotometry, Ultraviolet, Spectroscopy, Fourier Transform Infrared, Staphylococcus aureus drug effects, Staphylococcus aureus growth & development, Thermogravimetry, Ultraviolet Rays, X-Ray Diffraction, Zinc Oxide pharmacology, Zinc Oxide radiation effects, Aniline Compounds chemistry, Anti-Bacterial Agents chemistry, Copper chemistry, Nanocomposites chemistry, Zinc Oxide chemistry
- Abstract
Polyaniline/Cu(0.05)Zn(0.95)O (PANI/CZO) nanocomposites were prepared by in situ inverse microemulsion method. Based on the characterization of the crystal structure, chemical composition, and morphology of the samples, it was confirmed that CZO nanoparticles were incorporated into the polyaniline matrix. Studies of the antimicrobial activities of the samples against Staphylococcus aureus, Escherichia coli and Candida albicans were carried out using powder inhibition zone, minimum inhibitory concentration and minimal bactericidal concentrations methods. The results showed clearly that, as an antibacterial agent, PANI/CZO nanocomposites exhibited excellent antibacterial activity against the growth of microorganisms. Furthermore, the antibacterial mechanism of the samples was also deduced in this paper.
- Published
- 2012
- Full Text
- View/download PDF
34. An efficient and high-throughput electroporation microchip applicable for siRNA delivery.
- Author
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Huang H, Wei Z, Huang Y, Zhao D, Zheng L, Cai T, Wu M, Wang W, Ding X, Zhou Z, Du Q, Li Z, and Liang Z
- Subjects
- Animals, Cell Line, Cell Survival, Cells, Cultured, Electroporation economics, Equipment Design, Humans, Microfluidic Analytical Techniques economics, Transfection economics, Electroporation instrumentation, Microfluidic Analytical Techniques instrumentation, RNA, Small Interfering administration & dosage, Transfection instrumentation
- Abstract
Here we report a novel electroporation microchip with great performance and compatibility with the standard multi-well plate used in biological research. The novel annular interdigitated electrode design makes it possible to achieve efficient cell transfection as high as 90% under low-strength electrical pulses, thereby circumventing the many adverse effects of conventional cuvette-type and previously reported microchip-based electroporation devices. Using this system, we demonstrated substantially improved cell transfection efficacy and viability in cultured and primary cells, for both plasmid and synthetic siRNA. Improvements of this system open new opportunities for high-throughput applications of siRNA technology in basic and biomedical research.
- Published
- 2011
- Full Text
- View/download PDF
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