Separation cell-liquid

The separation schemes vary with the state of the products. For example, intracellular products must first be released by disrupting the cells, while those products bound to cell membranes must be solubilized. As the concentrations of products secreted into the fermentation media are generally very low, the recovery and concentration of such products from dilute media represent the most important steps in downstream processing. In this chapter, several cell-liquid separation methods and cell disruption techniques are discussed. 

Figure 9.1 Cell-liquid separation and further treatments.

I 9 Cell-Liquid Separation and Cell Disruption Suspension... 

Cell-Liquid Separation and Cell Disruption Equations 9.6a and 9.6b, respectively. Weight force = (nd ppg) /6... 

Separation applications Separation cell Separation, liquid-liquid Separation, low energy Separation, magnetic Separation nozzle Separation of fatty acids Separations... 

A Perkin-Elmer 5000 AAS was used, with an electrically heated quartz tube atomizer. The electrolyte is continuously conveyed by peristaltic pump. The sample solution is introduced into the loop and transported to the electrochemical cell. A constant current is applied to the electrolytic cell. The gaseous reaction products, hydrides and hydrogen, fonued at the cathode, are flowed out of the cell with the carrier stream of argon and separated from the solution in a gas-liquid separator. The hydrides are transported to an electrically heated quartz tube with argon and determined under operating conditions for hydride fonuing elements by AAS. 

The most widely used element-selective electrochemical detector is the Hall electrolytic conductivity detector (HECD) [98,116,206]. This is an improved version of an earlier design by Coulson [207,208]. In both detectors the reaction products are swept from the furnace into a gas-liquid contactor trtiere they are mixed with an appropriate solvent. The liquid phase is separated from insoluble gases in a gas-liquid separator and then passed through a conductivity cell. The Coulson detector employed a... 

Yan, F., Subramanian, B., Nakeff, A., Barder, T.J., Parus, S.J., Lubman, D.M. (2003). A comparison of drug-treated and untreated HCT-116 human colon adenocarcinoma cells using a 2-D liquid separation mapping method based on chromatofocusing pi fractionation. Anal. Chem. 75, 2299-2308. 

Buchanan, N. S., Hamler, R. L., Leopold, P. E., Miller, F. R., Lubman, D. M. (2005). Mass mapping of cancer cell lysates using two-dimensional liquid separations, electrospray-time of flight-mass spectrometry, and automated data processing. Electrophoresis 26(1), 248-256. Buick, R. N., Pullano, R., Trent, J. M. (1985). Comparative properties of 5 human ovarian adenocarcinoma celllines. Cancer Res. 45(8), 3668-3676. 

Hydrocyclones were originally designed to promote solid-liquid separations, but nowadays they are also used for solid-solid, liquid-liquid and gas-liquid separations. Possible new applications, such as cell separation, are being devel-... 

Extracellular enzyme Cell removal (solid liquid separation) Centrifugation Filtration... 

The introduction of hydrides into plasma-based instmmentation has also been achieved. The sensitivity increases markedly when compared with conventional nebulization because of the improved transport efficiency of the analyte to the atom cell (close to 100%). Often, a membrane gas-liquid separator is usee ensure that aerosol droplets of liquid do not reach the plasma. 

After removal of cells and debris from the culture or medium though solid-liquid separation, the fraction of recombinant protein in the liquid phase usually ranges from 2% to 15%. The large volumes associated with these low concentrations make it impractical to proceed to the next step in purification. Indeed, the volume may far exceed the capacity for chromatographic purification techniques used to isolate recombinant proteins from other soluble cellular contaminants. Therefore, a concentration step is used to reduce the volume and thereby increase the recombinant... 

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