Cross-Linked Casein Derivative from China
Cross-linked casein derivative features polymerized casein chains for biomedical coatings and slow-release fertilizers. It is covered by HTS 3501.90.60.00 as other derivatives, explicitly excluding hardened proteins of 3913. The cross-linking process defines its modified protein structure.
Duty Rate — China → United States
20%
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
9903.88.157.5%Except as provided in headings 9903.88.39, 9903.88.42, 9903.88.44, 9903.88.47, 9903.88.49, 9903.88.51, 9903.88.53, 9903.88.55, 9903.88.57, 9903.88.65, 9903.88.66, 9903.88.67, 9903.88.68, or 9903.88.69, articles the product of China, as provided for in U.S. note 20(r) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(s)
Import Tips
• Document cross-linking agent and degree of polymerization to exclude 3913 hardened proteins
• Obtain biotech end-use letters for dual commercial/research imports
• Use nitrogen solubility index tests (>70%) to affirm non-hardened status