Solid cell growth

Ennaoui, A. Weber, M. Saad, M. Harneit, W. Lux-Steiner, M. Ch. Karg, F. 2000. Chemical bath deposited Zn(Se,OH)x on Cu(In,Ga)(S,Se)2 for high efficiency thin film solar cells Growth kinetics, electronic properties, device performance and loss analysis. Thin Solid Films 361-362 450 153. 

Reactions of cell growth or those using immobilized enzymes are instances of gas-liquid-solid reactions. In principle, accordingly, any of the types of reactors described in Section 8.3 could be employed as fermentors. Mostly, however, mechanically agitated tanks are the type adopted. Aeration supplies additional agitation as well as metabolic need, and moreover sweeps away C02 and noxious byproducts. 

It should further be noted that the onset of continuity of the dispersed blend phase not only deteriorates the overall mobility of the SAN to form cellular structures, but also increases the average phase size of PPE and, thus, sterically hinders the incorporation into the cell walls. In particular, for the PPE/SAN 60/40 blend, showing some co-continuous features and solid-state characteristics at 180°C, the foamability is limited to such an extent that only local and less defined cell growth proceeds, leading to the highly inhomogeneous foam morphologies. 

However, as cell growth proceeds, the physical as well as chemical constraints of the triblock terpolymers inhibit pronounced growth within the PB phase. Instead, the nucleated cells tend to grow into the SAN/PMMA phase. As the PPE/PS phase still stores a significant amount of carbon dioxide, the blowing agent is subsequently transported along the interface towards the foam cells. Apparently the PPE/PS phase still acts similar to a solid phase. 

Cells are grown either in suspension in a free or immobilized form 102), or by adherence to a solid surface 100). Materials used for promoting surface-dependent cell growth are glasses, metals, plastics, carbohydrate polymers etc. the media used contain substances such as blood plasma, amniotic fluids, tissue extracts, etc.103). Recent developments in animal cell culture are aimed at the improvement of strains and culture techniques, medium optimization, and scale-up. In contrast to plant cell culture, animal cell culture has already found its technical application. Large-scale... 

In fermentation reactors, cell growth is promoted or maintained to produce metabolite, biomass, transformed substrate, or purified solvent. Systems based on macro-organism cultures are usually referred as tissue cultures. Those based on dispersed non-tissue forming cultures of micro-organisms are loosely referred as microbial reactors. In enzyme reactors, substrate transformation is promoted without the life-support system of whole cells. Frequently, these reactors employ immobilized enzymes, where an enzyme is supported on inert solids so that it can be reused in the process. Virtually all bioreactors of technological importance deal with a heterogeneous system involving more than two phases. 

A quantitative approach was taken to evaluate the effect of various concentrations of water extracts of the two crosslinked solids and individual liquid components on cell growth of L-929 cells in vitro. Both cells and adhesive materials were prepared as described above. For this assay, dilutions of an aqueous extract of the solids were prepared for a dose-response evaluation. The following weight per volume ratios were used 4,000, 500, 100, 50, 4, 3, 2, 1 fig per 20-mL water. Extraction was performed for 4 hr at 60 °C followed by 20 hr at room temperature. Supernatants were transferred to clean containers. The negative control consisted of sterile, triple distilled water, and the positive control was 40 mg/mL dextran sulfate. 

A second index of biocompatibility was the quantitative analysis of cell growth inhibition, again on mouse fibroblast L929 cells, induced by the liquid components of the adhesive system and water extracts of two solid crosslinked materials. Table IV is a summary of the percent inhibition of cell growth (percent ICG). The mean protein values at 4 °C have been subtracted from the mean protein values (five test samples) at 37 °C for each treatment condition. The percent inhibition of cell growth (percent ICG) is shown for each treatment condition. The precision of the assay is approximately 10%. 

Extracts of the low crosslinked solid also caused inhibition of cell growth in this assay. The percent ICG of the extracts ranged from 15.4 to 59.3%. Again, no dose response was apparent with the extracts of the low crosslinked solid. 

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