Hemodialysis

Dialysis is the diffusion of soluble particles from one fluid compartment to another compartment through the semipermeable membrane.

On Hemodialysis, blood is one of the compartment and the dialysate is the other part.
Semipermeable membrane is a sheet of thin, porous made of cellulose or synthetic material. Pore size membrane allows the diffusion of substances with low molecular weight such as urea, creatinine, and uric acid diffuse. Water molecule is also very small and move freely through the membrane, but most plasma proteins, bacteria, and blood cells are too large to pass through the membrane pores. The difference in the concentration of the two compartments is called the concentration gradient.

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