Properties of Sephadex gels and disadvantages:

The Sephadex gels and Bio-Gels show some striking similarities as given below:

i) Both gel types are macroreticular.

ii) The selectivity curve of both types of gels is similar.

iii) The mechanical properties of both types of gels are similar.

iv) The bead also shows similar behaviour. The bead with low water content is brittle and the one with high content of water are soft.

There are some disadvantages with Agrose gels which are as follows:

i) They contain a considerable amount of charged groups which cause problems due to ion exchange effects. To mitigate this problem, it is recommended to work at high ionic strength.

ii) Agar chains are not connected by covalent bonds. This makes the gels chemically unstable. These gels are less stable to pH extremes.

iii) The structure of agrose gels makes it impractical to dry and reswell them.

vi) Thus, once the gel is prepared it has to be stored in a wet state.

v) The selectivity curve is less steep than it is for gels from dextran and polyacrylamide.