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(4)2.pore transport/mechanism of drug transport

 2.pore transport

- It is also called as convective transport, bulk flow or filtration.

-the process is important in the absorption of low molecular weight (less than 100).

-low molecular size (small than the diameter of the pare) generally water-soluble drugs through marrow, aqueous filled channels or pores, in the membrane structure .ex :Urea, H₂o & Sugars....

* Chain-like.. or linear compounds of molecular weight upto 400 daltons can be absorbed by filtration.

* The driving force is constituted by the hydrostatic pressure/ the asmotic differences across the membrane due to which bulk flow of water along with solid molecules occurs through, aqueous such channels 

→water flux that promotes such a transport is called as solvent drug.

-drug permeation through water filled channels or of particular importance in renal excretion,removal of drug from the cerebrospinal fluid and entry of drugs into the liver.



Note:next topic will be continued I  next blog

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