Cleaning and Storage

GPC supports based on dextran (e.g., Sephadex) are cleaned from residual proteins by rinsing with five to ten bed volumes of 2 M NaCl, 0.1 M NaOH, or detergent as 0.1% Tween 20. Equilibrate the column after cleaning with ten bed volumes of elution buffer. Agarose-based beds, e.g., Sepharose or Biogel A, are freed from pollutions by sodium chloride, detergent, or 6 M urea. 

Store the GPC media at neutral pH in a refrigerator in the presence of an antibiotic, e.g., 0.02% sodium azide or 0.1% Thimerosal, or in 20% ethanol or i-propanol. 

Apply 0.5 ml of Soln. B as described in part 3.3.3 and continue the elution with Soln. A. Monitor the elution either continuously by UV measuring at 280 nm or by collecting 1-ml fractions, which are measured at 280 nm. Plot the optical density against elution volume (cf Fig. 3.4). The void volume Vq is the volume at maximal optical density. 

For determination of the total volume Vt use Soln. C instead of Soln. B. 

Calibrate a GPC column for molar weight determination analogously. Use a set of defined proteins or polypeptides as standards (see inset in Fig. 3.4). If the mass differences allow a complete separation, the proteins can be applied as a mixture. 

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These steel precision works of art have at least a mirror finish on the melt flow channel orifice surfaces. The slightest minute scratches can produce flaws in the extruded products. Great care must be used during their installation, operation, removal, cleaning, and storage. When designing them the target is to use as few parts as possible. The dies should be easily lifted for installation or maintenance, easily disassembled, easily cleaned, and easily reassembled. 

The process operation involves flve stages in a cycle that is to be completed in a total duration of 12 h which includes 10 h for the flve-stage operation, 1.5 h for reject recycle to feed tank, and 0.5 h for membrane cleaning and storage. The detailed explanation of the process in accordance is given below. 

There should be documented evidence to indicate that routine cleaning and storage of equipment does not allow microbial prohferation. 

A number of problems can be avoided by careful cleaning and storage of glassware dedicated to a particular purpose. Preparation of dilute standard solutions from concentrated stock solutions just before use will minimize problems caused by instability and adsorption. 

Scale-down studies have been used for a wide variety of process validation studies, including resin lifetimes, in-process stream hold times, buffer stability, virus clearance, harvest criteria, filter extractables, resin leachables, and cell age at harvest [14, 91, 92]. The ease of scale-down differs depending on step and should be considered in selecting those steps to be validated [5]. In fact, certain validation issues can be addressed only via small-scale models (e.g., virus clearance evaluation, nucleic acid and other impurities/additives removal, cleaning and storage procedure evaluation, and column lifetime estimation) because their use increases worker safety, reduces costs, and permits use of higher titer samples for improved... 

Cleaning and storage of respirators assigned to specific employees are the... 

Ensure that the mask is clean. A dirty or deteriorated mask will not seal properly, nor will one that has been stored in a distorted position. Proper cleaning and storage procedures must be used. 

Cleaning and storage of assware, filters, chemicals and solvents... 

The larger the pipe diameter, the larger the volume of drilling fluids that must be pumped, requiring larger pumps and mud-cleaning and storage equipment... 

The licensed applicator should be made familiar with the various types of hand, ground, and aerial equipment available and with the various parts and functions of spray equipment. The applicator must be skilled in sprayer equipment calibration, maintenance, cleaning, and storage. The applicator should know that proper calibration of spray... 

Table 4.8 provides the complete operation and maintenance cost of RO system, which includes power, membrane module and micron filter cartridge re-plaeement costs, chemical consumption for cleaning and storage, etc. Feed capacity and recovery were assumed to be 2 m /h and 60%, respectively. The operational time for system was assumed to be 10 h per day in view of the fact that electric power supply in remote villages is restricted to a few hours per day. Depreciation costs were taken as 10% of the total capital investment while life of hardware is expected to be 10 years. Membrane life was foimd to be 3 years as per data collected at village sites where plants have been operated. 

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