Phenylmercuriborate solution is not available. Can this be replaced in the preparation of next eye drops?

As a preservative comes with what is currently still available only Nipagine-Nipasol are eligible.  

According to the common theory, an incompatibility between fluorescein and oxybuprocaineH + could occur. I underline "can".  

For the isotonic I would use glucose here that is non-ionogen.