Page 305 - Biosystems Engineering

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in terms of active product content as well as in terms of the
absence of specific impurities. Injectable therapeutic products
should be free from endotoxins and pyrogens.
3. Bioseparation processes involved in biotechnology industries
tend to depend on off-the-shelf equipment. Bioseparation is
frequently based on multitechnique separation.
4. Many biological products are thermolabile, and hence many
bioseparation techniques are usually carried out at subambi-
ent temperatures and avoid extremes of physicochemical
conditions such as pH and ionic strengths, hydrodynamic
conditions such as high shear rates, and exposure to gas–liquid
interfaces. Organic solvents, which are widely used in chemi-
cal separations, have relatively limited usage in biosepara-
tion because of their tendency to promote degradation of many
biological products.

The main disadvantages of bioseparation processes are as follows:
1. High capital cost
2. High operations cost
3. Lower product recovery
4. Requires highly technical scientists (knowledge of both biol-
ogy and engineering)
5. Requires special safety protection

9.2 Different Stages of Bioseparation Process
Bioseparation processes depend on the following stages:
1. Reduction in bulk or concentration enrichment → Evaporation
or distillation in vacuum or extraction
2. Remove insoluble impurities → Filtration or centrifugation
3. Isolation of the product → Extraction or adsorption
4. Purify the product → Chromatographic technique
5. Polish → Drying or crystallization designed to remove sol-
vent, such as water or trace amount of impurities

After final polishing (step 5), required steps are effluent treatment
produced in the different stages of bioseparation process.

Upstream → Bio reaction → Downstream → Bio products
Processing Processing → Impurities