(A) Graph depicts a linear curve with various gold (Au)
concentrations, translating into gold per gram of tissue, that confirms
the presence of gold in mouse and human tissues. The 1000 µg/mL
stock solution of platinum diluted to 0.4 µg/mL with 2% (w/v)
nitric acid + 0.5% hydrochloric acid (w/v) is used as an internal
standard. (B) Inductively coupled plasma mass spectrometry
(ICP-MS) instrument parameters used in the gold analysis.
(C) Comparison of the actual versus calculated gold
concentrations observed during the ICP-MS analysis. (D)
DY36T2Q breast tumors from mice had a gold content of 15 μg of
gold per gram of tissue (P < .001) compared with
4 μg/g of gold observed in splenic tissue. (E)
ICP-MS analysis of human epidermal growth factor receptor 2
(HER2)–positive human breast tumors indicated 22 μg of
gold per gram of tissue (P =
.039).*** = P < .001,
*= P < .05, BEC = blank equivalent
concentration, DL = detection limit, Temp = temperature, TRA =
trastuzumab.