Magnetic Tweezers‐Based 3D Microchannel Electroporation for High‐Throughput Gene Transfection in Living Cells

A novel high‐throughput magnetic tweezers‐based 3D microchannel electroporation system capable of transfecting 40 000 cells/cm² on a single chip for gene therapy, regenerative medicine, and intracellular detection of target mRNA for screening cellular heterogeneity is reported. A single cell or an ordered array of individual cells are remotely guided by programmable magnetic fields to poration sites with high (>90%) cell alignment efficiency to enable various transfection reagents to be delivered simultaneously into the cells. The present technique, in contrast to the conventional vacuum‐based approach, is significantly gentler on the cellular membrane yielding >90% cell viability and, moreover, allows transfected cells to be transported for further analysis. Illustrating the versatility of the system, the GATA2 molecular beacon is delivered into leukemia cells to detect the regulation level of the GATA2 gene that is associated with the initiation of leukemia. The uniform delivery and a sharp contrast of fluorescence intensity between GATA2 positive and negative cells demonstrate key aspects of the platform for gene transfer, screening and detection of targeted intracellular markers in living cells.     

Studies on cellulose acetate–polysulfone ultrafiltration membranes: I. Effect of polymer composition

Ultrafiltration techniques have particular advantages for simultaneous purification, concentration and fractionation of macromolecules. Studies are presented on novel ultrafiltration membranes, based on cellulose acetate and polysulfone blends, for the separation of proteins and heavy metal ions. The effects of polymer composition on pure water flux, water content, molecular weight cut‐off and hydraulic resistance are discussed. Scanning electron microscopy images of the membranes show the presence of segregated individual domains of cellulose acetate and polysulfone. The molecular weight cut‐off obtained from the protein separation studies is also presented. Applications of these membranes for separating metal ions from aqueous streams are discussed. Copyright © 2005 Society of Chemical Industry     

Site‐specific delivery of green tea coated aluminium magnesium silicate beads and studies on their effect against chicken coccidiosis

In this report, the site‐specific co‐delivery of green tea/aluminium magnesium silicate (AMS) was reported and the specific target delivery was achieved orally. The new co‐precipitation process was developed to synthesis the green tea/AMS hybrid complex and using energy‐dispersive X‐ray spectroscopy, Fourier‐transform infrared spectroscopy and Raman confirmed its successful synthesis. The blood biocompatibility of the green tea/AMS was tested using chicken blood, and the compound is safe up to 500 mg/ml. After mixed with hydroxypropyl methylcellulose phthalate, the oral beads were synthesised using a linking agent. The oral beads underwent different pH‐based dissolution studies and the results indicated that the beads specifically dissolved in gastric pH (6.5). The pharmaco kinetic studies were performed to estimate the delivery kinetics. The results revealed that the beads underwent as per the Higuchi model. The anticoccidial effects of the beads were tested using chicken. The animal studies were performed in two different modes such as prophylactic treatment and active treatment after Eimeria species challenge. The results indicated that the prophylactic treatment with beads 100% protected the chicken and the active treatment with beads after the Eimeria challenge significantly protected against the intestinal damage and it also enhanced the anticoccidial effect.Inspec keywords: X‐ray chemical analysis, drug delivery systems, pH, drugs, biomedical materials, blood, dissolving, Fourier transform infrared spectra, Raman spectra, aluminium compounds, magnesium compounds, precipitation (physical chemistry), materials preparationOther keywords: prophylactic treatment, active treatment, anticoccidial effect, green tea coated aluminium magnesium silicate beads, chicken coccidiosis, target delivery, Fourier‐transform infrared spectroscopy, blood biocompatibility, chicken blood, hydroxypropyl methylcellulose phthalate, oral beads, pharmacokinetic studies, delivery kinetics, animal studies, site‐specific codelivery, pH‐based dissolution, coprecipitation process, green tea‐AMS hybrid complex, energy‐dispersive X‐ray spectroscopy, Raman spectroscopy, linking agent, gastric pH, Al₂ Mg₃ O₁₈ Si₆ , intestinal damage, Eimeria species, anticoccidial effects, Higuchi model     

Keratin hydrolysate as an exhausting agent in textile reactive dyeing process

Salt is an essential exhausting agent for the dyeing of cotton fabric with reactive dyes. The usage of salt leads to an increased effluent load in terms of total dissolved solids and also limits the opportunities for recycling textile dye house effluents. These effluents are difficult to degrade and their disposal leads to environmental pollution. In the present work, we have prepared keratin hydrolysate (KH) from waste of wool processing industries to reduce the usage of salt in dyeing. The KH was fixed to the cotton fabric at five different add on percentage, and the presence of the KH on the fabric was confirmed by FTIR, TGA and SEM-EDX Studies. The KH-fixed fabrics were further dyed with reactive dyes without addition of salt. The colour strength of the fabric increased up to 91 % to that of the control sample. The studies reveal that the tone of the fabric was not altered and KH usage can significantly reduce salt consumption in reactive dyeing process.     

Effect of Load and Composition on Friction and Dry Sliding Wear Behavior of Tungsten Carbide Particle-Reinforced Iron Composites

Investigations on the dry sliding wear behavior of tungsten carbide (WC)-reinforced iron matrix composites were carried out at room temperature. Three sets of samples (unreinforced iron, 4 wt% micrometer-size (～5–15 μm) WC-reinforced iron and 4 wt% nanosize (～30 nm) WC-reinforced iron were prepared using a powder metallurgy route to assess their friction and wear behaviors under two different loads. The relative dry sliding wear performances of the micrometer-size and nanosize WC-reinforced composites were compared with unreinforced matrix. An increase in microhardness of the order of 2.5 times was observed in the case of 4 wt% nanosize WC-reinforced iron matrix compared to the unreinforced iron matrix. The wear rate was 1.35 to 1.45 times lower in the case of nanocomposites compared to the unreinforced iron matrix (under different experimental conditions). The values of the coefficient of friction (COF) of composites were found to decrease with increase in load. Nanocomposites showed lower COF, surface roughness, and fractal dimension (D) values than micrometer-size WC-reinforced composites and the unreinforced iron matrix.     

Guest editorial: New trends in data pre-processing methods for signal and image classification

Neural Computing and Applications -