News tagged with membrane

Related topics: cells , cell membrane

To stop cancer: Block its messages

The average living cell needs communication skills: It must transmit a constant stream of messages quickly and efficiently from its outer walls to the inner nucleus, where most of the day-to-day decisions ...

Mar 30, 2015
popularity 15 comments 0

Hunting the ion channel

The electrical impulse that powers the workings of the brain and the heart begins with charged particles passing through cellular structures known as ion channels. Using the same technique used to decode ...

Mar 24, 2015
popularity 8 comments 0

Study sheds new light on asthma, COPD

In diseases such as asthma and chronic obstructive pulmonary disease (COPD), the body produces too much mucus, making breathing difficult. New research from Washington University School of Medicine in St. ...

Mar 18, 2015
popularity 20 comments 0

Membrane

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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