Mutations of specific amino acids in ALS have been known to confer resistance to ALS-inhibiting herbicides such as sulfonylureas and pyrimidinyl carboxy (PC) herbicides.

Objective: To establish an HPLC method to determine the plasma concentrations of buspirone hydro-chloride (BuHCl) and its active metabolite 1 - pyrimidinyl - piperazine(1 - PP).