I am looking to assay sorbitol in a protein solution (45g/l)and also in the presence of acetate(20mmol) and glycine (35mmol). Any information on an HPLC method would be grateful.

In my laboratory we ROUTINELY, easily assay for materials such as this (propylene glycol, glycerine, butanediol, sorbitol) by GC by dissolving sample in N,N-dimethylformamide (up to 2.5% sample in DMF) then mixing two parts sample with one part BSTFA derivatizing agent and assaying by methyl silicone capillary column connected to FID. These types of materials can all be quantitated in one run, and even trace levels can be quantitated, using either internal or external standard. I have published two papers on this in JAOCS, first one in 1982.