Pack costs testing

Based on the requirements of the separation, media of suitable pore size, particle size, and surface properties are selected as well as column dimensions and column material. In some cases a suitable combination of media type and column dimensions may be available as a prepacked column. In most cases, this is a more expensive alternative to preparing the column yourself but will provide a consistent quality as assured by the manufacturing and testing procedures of the vendor. The consistent quality may be critical in obtaining reproducible results and may thus be a cost-effective solution. Also, the fact that smaller particle-sized media are more difficult to pack and require special, and expensive, equipment has resulted in that gel filtration media of small particle size, e.g. smaller than 15 /zm, are predominantly supplied as prepacked columns. 

Succinic acid was removed from medium on a packed column of sorbent. The resin XUS 40285 was tested in a packed column with simulated medium containing salts, succinic acid, acetic acid, and sugar. The packed column completely separated the fermentationbyproduct, acetate, from succinate. A simple hot water regeneration successfully concentrated succinate from 10 g/L (inlet) to 40-110 g/L in the effluent with a pH of about 5.0. The end pH indicates that succinate salt was sorbed from the "medium" and released in a partially acidic form by the hot water regeneration. If successful, this would lower separation costs by reducing the need for chemicals for the initial purification step. 

Hollow Fiber Small footprint Low capital cost Can be backwashed Can easily be integrity tested High membrane area per unit volume (high packing density) Plugging of fiber (inside-out feed) Bridging of fiber bundle (outside-in feed) Difficult to clean... 

Tablets can also be photostabilized using aluminum blister packs. This photostabilization method is used by some nifedipine tablet manufacturers. Nifedipine tablets packaged in aluminum foil unit dose blisters do not require any additional photo protection (e.g., coating), providing a significant saving in development and manufacturing costs as well as stability testing (40).

Basically each overwrap changes the gradient around the pack (between the inside and outside of the pack) and adds an additional barrier through which moisture has to permeate. Theoretical calculations for a multiplicity of barrier layers need a fairly complex mathematical appreciation and practical estimates may be equally difficult, as either a pallet will not enter a climatic cabinet or the cost of samples could be prohibitively high, with an expensive product kept on test for a prolonged period. 

The future control of the product and pack then revolves around these documents. In the case of a plastic pack or plastic components, it may be necessary not only to define certain critical factors in the specification tightly, but also to purchase under a certificate of warranty, as exhaustive QC procedures (particularly biological tests), which might be necessary to detect change, could involve prohibitive costs. Regular QC checks are likely to include melt flow index, density, IR or DSC identity, etc. The last two are a particularly useful means of providing plastic identification, with DSC now more widely used. 

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