今天看agilent的应用手册,看到这么几句。Since the analytes and internal standard should show the same behavior,the internal standard elements should be selected to have mass numbers and /or ionization potentials similar to the analytes: Bi(209amu) is good internal for Pb(208amu), Zn(9.39ev) is good for Cd(8.99ev) because of similar ionization potential. Zn Cd的虽然电离能相近,但质量数差别那么大,能做为Cd的内标吗??