Bioseparation

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Bioseparation

• Bioseparation or downstream processing refers to
  separation and purification of products
  synthesized by bioprocesses
• r-DNA Technology
• Fermentation
• Enzyme technology
• Cell culture
• Bioproducts
• Present in very low concentrations
• Present along with a large number of impurities
• Thermolabile
• Sensitive to operating conditions such as pH and
  ionic strength.
• Have stringent quality requirements

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Economic importance of bioseparation
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The RIPP scheme
This scheme involves using low resolution -
high-throughput techniques first followed by high
resolution - low throughput techniques

• High resolution-low throughput
• Ultracentrifugation
• Adsorption
• Packed bed chromatography
• Affinity separation
• Electrophoresis

• High resolution-high throughput
• Ultrafiltration
• Membrane chromatography
• Fluidised bed chromatography

• Low resolution-high throughput
• Cell disruption
• Precipitation
• Centrifugation
• Liquid-liquid extraction
• Leaching
• Filtration
• Supercritical fluid extraction
• Microfiltration

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Cell disruption

• Biotechnological products are extracellular or
  intracellular
• Physical methods for cell disruption
• Disruption in ball mill or pebble mill
• Disruption using a colloid mill
• Disruption using French press
• Disruption using ultrasonic vibrations
• Chemical methods for cell disruption
• Disruption using detergents
• Disruption using enzymes e.g. lysozyme
• Combination of detergent and enzyme
• Disruption using solvents

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Cell disruption equipment
Cascading balls/pebbles
Biological material being disrupted
Rolling balls/pebbles
Rotor
Disrupted cells
Plunger
Cylinder
Cell suspension
Jet
Stator
Orifice
Impact plate
Feed
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Precipitation

• Proteins can be precipitated using
• Salting out salts like ammonium sulphate and
  sodium chloride
• Solvents like ethanol, methanol and acetone
• Concentrated acids or alkali

• Nucleic acids can be precipitated using
• Organic solvents
• Phenol

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Centrifugation

• A centrifuge separates particles from solution by
  artificially induced gravitational field
• Particles
• Cells
• Sub-cellular components
• Proteins and DNA
• Basis
• Size
• Shape
• Density
• Viscosity
• Types
• Analytical centrifugation 1 1000 ml lt10000 rpm
• Preparative Centrifugation 1- 1000s litres 1000
  rpm

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Centrifuges
Supernatant
Supernatant
Centrifuge tube
Precipitate
Tubular bowl
Precipitate
Rotor
Feed
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Electrophoresis

• Electrophoresis separates compounds by using an
  electric field in a conducting medium
• Basis Charge, shape, size, property of medium
• Types Gel, Liquid phase

Medium
Positive electrode
Negative electrode
Power source