Thank you sir for the reply. It helped me to clear my most of the doubt.

I would say you just have to do the calculation based on the stoichiometry. For example:

I mol TEOS contains 1 mol of Si and should give you 1 mol of SiO2 ~ 60 g

I mol TEP contains 1 mol of P and should give you 0.5 mol of P2O5 ~ x g

.....

Then you have to set a targeted amount of total bioactive glass and consider the amount of each component i.e. CaO, SiO2, or P2O5 needed in it.

With backward calculation you should be able to say how much of each precursor material you need.

Also what you need to pay attention to is that when you add Ca, Na, Mg, Zn, Sr etc to the system, they are also soluble in pore liquor and this is why the pore liquor shouldn't be thrown away (otherwise you will lose most of those ions and end up with amorphous silica).

In order to have a more homogeneous distribution of Ca, Na, ... you can ball-mill the dried gel before final calcination. This shortens the path needed for diffusion of ions into the preformed silica matrix.

This paper is a good one:

Article Nanostructure Evolution and Calcium Distribution in Sol–Gel ...