After separation of PHA from the biomass, it is usually converted to crotonic acid which is measured with respect to standard to find out the quantity and quality of PHA produced.

If I am to separate PHA and the proteins after detergent treatment, how do I measure the amount of protein removed from PHA or still bound to PHA (as we all know that conc. sulphuric acid denature's proteins) before converting PHA into crotonic acid