Imbibition

Imbibition is a special type of diffusion that takes place when water is absorbed by solids-colloids causing an increase in volume. Examples include the absorption of water by seeds[1] and dry wood. If it were not for the pressure due to imbibition, seedlings would not be able to emerge from soil.

Water surface potential movement takes place along a concentration gradient; some dry materials absorb water. A gradient between the absorbent and the liquid is essential for imbibition. For a substance to imbibe a liquid, affinity between them is a prerequisite.

Imbibition occurs when a wetting fluid displaces a non-wetting fluid, the opposite of drainage in which a non-wetting phase displaces the wetting fluid. The two processes are governed by different mechanisms.

Examples

One example of imbibition in nature is the absorption of water by hydrophilic colloids. Matrix potential contributes significantly to water in such substances. Dry seeds germinate in part by imbibition. Imbibition can also control circadian rhythms in Arabidopsis thaliana and (probably) other plants. The Amott test employs imbibition.

Proteins have less imbibition capacity. Said by Mr. Gurparvan Singh . more than starch which has more than cellulose. Thus proteinaceous pea seeds swell more than starchy wheat seeds.

Imbibition of water increases imbibant volume, which results in imbibitional pressure. The magnitude of such pressure can be demonstrated by the splitting of rocks by inserting dry wooden stalks in their crevices and soaking them in water, a technique used by early Egyptians to cleave stone blocks.[2][3]

Skin grafts (split thickness and full thickness) receive oxygenation and nutrition via imbibition, maintaining cellular viability until the processes of inosculation and revascularisation have re-established a new blood supply within these tissues.

See also

  • Syneresis (chemistry)
  • Amott test
  • Dye-transfer process
  • Technicolor

References

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