Phosphotungstic Acid Sodium Salt from China
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 — China → United States
30.5%
Rate breakdown
9903.91.0125%Effective with respect to entries on or after September 27, 2024, articles the product of China, as provided for in subdivision (b) of U.S. note 31 to this subchapter
9903.05.860%Universal product exemption (U.S. note 52(b))
Import Tips
• Heteropolyacid structure confirmed by 31P NMR to avoid phosphate heading
• Histology stain requires biological safety level declarations
• Light-sensitive; amber packaging recommended