Cell Disruption is a process of releasing the biological content from a cell or a process of obtaining intracellular fluid via methods that opens up cell wall. An overall goal in cell disruption is to obtain intracellular fluid without disrupting any of its components.
It is of two types: Mechanical and Non-mechanical.
Mechanical method of cell disruption can be divided into solid shear methods and liquid shear methods. The major principle of mechanical disruption method is cells are being subjected to high stress via pressure, abrasion with rapid agitation with beads, or ultrasound. Intensive cooling of suspension after treatment is required in order to remove heat generated by dissipation of mechanical energy.
It is a physical method for rupturing mammalian and plant cells by shear force. In this method, tissue is cut into small pieces and blended with buffer for about 1 minute to disrupt the cell. It is centrifuged to remove the debris.
The process is usually carried out in a typical domestic kitchen blender. A blender can be used for microorganism if small glass beads are introduced to blender which produce bead mill. In this process, cells are trapped between colliding beads then get disrupted. As beads helps to crush microbial cells, the process is also known as data mining.
Grinding with Abrasives
It is a method to rupture cell in presence of abrasives like sand, alumina, glass beads, etc. It can be carried out in mortar piston, dynomill etc.
Grinding in mortar and piston with sand or alumina in presence of buffer cause rupturing of cell wall. This method is useful for disrupting bacterial or plant cells. However, relatively small amount of sample can be processed.
Large scale version of grinding in mortar and piston is dynomill which is an electrical process. It comprises a chamber containing glass beads and numbers of rotating impeller discs. Cells get ruptured when they are caught between colliding beads. It can process upto 5kg cells/hour. This method helps in production of industrially important proteins and enzymes.
It is a mean of disrupting microbial cells by the application of pressure. This technique is also called high pressure homogenizer and is carried out by press such as French press, X-press, Hughes press, etc.
In this method, cell suspension is drawn through a valve into a pump cylinder and is forced under pressure of up to 1500 bar, through narrow annular gap and discharge valve, where pressure drops to atmospheric. Cell disruption is achieved due to sudden drop in pressure upon discharge, causing the cells to explode.
French press uses high pressure to disrupt cell. A cell suspension is forced by a piston type pump under high pressure through a small orifice which causes rapid drop of pressure when cells emerge from orifice that allows previously compressed cells to expand rapidly and hence cell burst. Usually, 10,000 PSI is applied to cell for the disruption.
In X-press cell is often mixed with abrasive and they are frozen to form a paste which is then forced through orifice. Both abrasive and ice crystal formed during freezing aid in disruption of cells.
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