Dithiothreitol (DTT) from China
Dithiothreitol is a 1,4-dithiol compound (HOCH2(CHOH)2CH2SH)2 with two SH groups directly attached to carbon atoms. HTS 2930.90.92 covers this as other organo-sulfur compound used as reducing agent in biotech. Meets chapter definition for separate chemically defined compounds.
Duty Rate — China → United States
16.2%
Rate breakdown
9903.05.3112.5%Except for products described in headings 9903.05.85–9903.05.92, articles the product of China, as provided for in U.S. note 52 to this subchapter
Import Tips
• Specify biotech/pharma end-use on entry documents to justify Chapter 29 classification
• Maintain cold chain documentation if shipped refrigerated per stability requirements
• Avoid bulk packaging that suggests industrial chemical use triggering different scrutiny