Related topics: cells · cell membrane

Uncovering the role of membrane sugars in flu infection

The flu virus relies on using human cells to reproduce and spread. But before it even gets to the cell surface, the virus must navigate the tall, dense forest of sugar-coated proteins on the cell surface known as the glycocalyx. ...

Terrestrial bacteria can grow on nutrients from space

In the past decade, there has been renewed thinking about human missions to the moon and perhaps even to Mars. Inevitably, terrestrial microorganisms on the bodies of astronauts, spaceships or equipment will come into contact ...

A replaceable, more efficient filter for N95 masks

Since the outbreak of COVID-19, there's been a worldwide shortage of face masks—particularly, the N95 ones worn by health care workers. Although these coverings provide the highest level of protection currently available, ...

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A membrane is a layer of material which serves as a selective barrier between two phases and remains impermeable to specific particles, molecules, or substances when exposed to the action of a driving force. Some components are allowed passage by the membrane into a permeate stream, whereas others are retained by it and accumulate in the retentate stream.

Membranes can be of various thickness, with homogeneous or heterogeneous structure. Membrane can also be classified according to their pore diameter. According to IUPAC, there are three different types of pore size classifications: microporous (dp < 2nm), mesoporous (2nm < dp < 50nm) and macroporous (dp > 50nm). Membranes can be neutral or charged, and particles transport can be active or passive. The latter can be facilitated by pressure, concentration, chemical or electrical gradients of the membrane process. Membranes can be generally classified into three groups: inorganic, polymeric or biological membranes. These three types of membranes differ significantly in their structure and functionality.

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