Phosphotungstic Acid Sodium Salt from Mexico
Sodium phosphotungstate (Na3PW12O40) is used in analytical chemistry for protein precipitation, classified as a tungstate under HTS 2841.80.00 despite phosphate group.
Duty Rate — Mexico → United States
5.5%
Rate breakdown
9903.03.030%Articles the product of any country, as provided for in subdivision (aa)(ii) of U.S. note 2 to this subchapter
Import Tips
• Heteropolyacid structure confirmed by 31P NMR to avoid phosphate heading
• Histology stain requires biological safety level declarations
• Light-sensitive; amber packaging recommended