The measurements were performed by using Absorption flame AAS technique with single beam mode. The background correction mode is deuterium background correction. This method describes a procedure for the determination of gold in serum and may be applicable to urine.

The measurements were performed by using Absorption flame AAS technique and hydride technique with single beam mode. The background correction mode is deuterium background correction. Sample preparation：Weigh sample 0.3g into digestion vessel， Add 5ml  HNO3， Digest sample as the temperature below.

The measurements were performed by using Absorption flame AAS technique and hydride technique with single beam mode. The background correction mode is deuterium background correction.  Sample preparation: Pipette 1 ml of cough medicine into digestion vessel，Add 5ml HNO3  and 2ml H2O2  and  leave the sample in Fume hood for 15-20 minutes，Digest sample as the temperature.