can you convert a string to an instance variable

HI

Is it even possible to do this?

here is what we are trying to do
code:
cellNumber:= 'cell', ((3*(aRow-1) + aColumn)) asString.

... then we want to  try to use "cellNumber" as an instance variable so we can access a method

Maybe there is some other way to do what we want to do ... but ??? It seems that it's just a matter of some
kind of conversion from "string" to "instance variable", but what ???

thanks for any help on this,