FDA Reference Standard Saxitoxin is now available from the US National Institute of Standards and Technology (NIST). To order, go to the standard reference materials page of the NIST web site
http://www.nist.gov/srm
and enter
8642
in the 'SRM/RM Number' box, or enter
saxitoxin
in the 'Keywords' box.
Orders may be placed by telephone at 301-975-2200 or by fax 301-948-3730 or by email srminfo@nist.gov.
The vials are each 1.2 mL as before, but the unit of issue is now 10 vials. When the FDA distributed SSTX directly it was sent out in units of 3 vials. The charge listed for a NIST unit of 10 vials is $361.
Comparisons of this lot (Lot 089) with the previous lot of SSTX (Lot 088) indicate that they have the same concentration. However, the standard is now packaged with the intent that it be diluted by mass, instead of by volume. Follow the instructions included with the standard.