Tromethamine (Tris(hydroxymethyl)aminomethane) from Mexico
Tromethamine, or Tris base, is an amino-triol used as a biological buffer and pharmaceutical excipient, falling under HTS 2922.19.96 for oxygen-function amino-alcohols. It is a separate chemically defined compound as specified in Chapter 29 notes.
Duty Rate — Mexico → United States
16.5%
Rate breakdown
9903.05.5510%Except for products described in headings 9903.05.85–9903.05.92 and 9903.05.94, articles the product of Mexico, as provided for in U.S. note 52 to this subchapter
Import Tips
• Provide USP/EP certificates for pharmaceutical grade to facilitate FDA customs clearance
• Declare as 'biological buffer' but emphasize pure compound status to maintain Chapter 29 classification
• Ensure stabilizer content <1% to avoid reclassification per chapter preservation notes