N-Hydroxysuccinimide (NHS) from Mexico
N-Hydroxysuccinimide is an activated ester/imide used in peptide synthesis and bioconjugation chemistry. The imide ring structure qualifies it for HTS 2925.19.91.00 as 'other' imide derivatives despite hydroxy substitution.
Duty Rate — Mexico → United States
110%
Rate breakdown
9903.04.6096.3%Except as provided in heading 9903.04.61, patented pharmaceutical articles as provided for in subdivisions (c) and (d) of U.S. note 40 to this subchapter
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
• Biotech end-use requires FDA DMF or equivalent; research use exempt
• Moisture sensitive; specify <0.5% water content on CoA
• Common with EDC coupling agent; declare separately to avoid set classification