Related topics: cells · cell membrane

New membrane efficiently separates mirrored molecules

Prof. Liu Bo and colleagues at the University of Science and Technology of China (USTC) have developed a chiral separation membrane capable of capturing left-handed chiral molecules and releasing the right-handed counterpart ...

Fungus produces highly effective surfactant

Mortierella alpina lives in the soil and likes to keep cool. This fungus, which belongs to the zygomycetes, grows best at temperatures of 10 to 15 degrees C and occurs mainly in alpine or arctic habitats. In biotechnology, ...

Preventing drugs from being transported from cells

An international research team has investigated the transport mechanism of a bacterial membrane protein using an artificially produced antibody fragment. The transport proteins, called ABC exporters, are present, for instance, ...

A microscopic topographic map of cellular function

The flow of traffic through our nation's highways and byways is meticulously mapped and studied, but less is known about how materials in cells travel. Now, a team of researchers at the University of Missouri is challenging ...

Learning from nature's bounty: New libraries for drug discovery

Natural products, or their close derivatives, make some of our most potent medicines, among which macrocycles with their large carbon-rich ring systems are one class. The size and complexity of macrocycles has made it difficult ...

Getting the oil out of befouled water

Oil and water are famously reluctant to mix fully together. But separating them completely—for example, when cleaning up an oil spill or purifying water contaminated through fracking—is a devilishly hard and inefficient ...

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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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