<P> Dialysis tubing, also known as Visking tubing, is a type of semi-permeable membrane tubing used in separation techniques, that facilitates the removal or exchange of small molecules from macromolecules in solution based on differential diffusion . In the context of life science research, dialysis tubing is typically used in the sample clean - up and processing of proteins and DNA samples or complex biological samples such as blood or serums . Dialysis tubing is also frequently used as a teaching aid to demonstrate the principles of diffusion, osmosis, Brownian motion and the movement of molecules across a restrictive membrane . For the principles and usage of dialysis in a research setting, see Dialysis (biochemistry). </P> <P> Dialysis occurs throughout nature and the principles of dialysis have been exploited by humans for thousands of years using natural animal or plant based membranes . The term dialysis was first routinely used for scientific or medical purposes in the late 1800s and early 1900s, pioneered by the work of Thomas Graham . The first mass - produced man - made membranes suitable for dialysis were not available until the 1930s based on materials used in the food packaging industry such as Cellophane . In the 1940s, Willem Kolff constructed the first dialyzer (artificial kidney), and successfully treated patients with renal failure using dialysis across semi-permeable membranes . Today, dialysis tubing for laboratory applications comes in a variety of dimensions and molecular - weight cutoffs (MWCO). In addition to tubing, dialysis membranes are also found in a wide range of different preformatted devices, significantly improving the performance and ease of use of dialysis . </P>

What is dialysis tubing and why is it a good model for real cells
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