Chemical Stability and Compatibility - Are your mercury standards stabilized with Au?

Our stock catalog items for Hg do not come stabilized with Au.  If the matrix is HCl, the product comes in LDPE and is stable.  If the matrix is HNO₃, the product comes in borosilicate glass and is also stable.  For certain custom products where a customer requires low levels of elements and requires HNO₃ matrix as opposed to HCl, we will stabilize Hg with 1ppm AuCl₃ as recommended by the EPA.  Those products are also stable. For low level blends, we cannot use borosilicate glass due to the contamination present in that type of container.  If the blend can be in HCl, the Au is not required to achieve long term stability and can be stored in a clean LDPE bottle.  If the blend has to be in HNO₃, due to the analyst’s desire to quantify As and Se by ICP-MS with minimal ArCl interference, we use Au to stabilize the Hg.  There will be minimal Cl present, which aids in the testing of As and Se with Hg in the same standard.Please let us know if you have any additional questions.