2923.20 - Lecithins and other phosphoaminolipids:

HTS code 2923.20 specifically encompasses lecithins and other phosphoaminolipids, which are a class of naturally occurring or synthetically produced compounds containing both phospholipid and amino groups. These substances are often characterized by their amphipathic nature, meaning they possess both hydrophilic and hydrophobic properties, making them valuable emulsifiers and components in biological systems. This classification distinguishes itself from sibling categories such as choline and its salts (2923.10) and certain specific perfluorooctane sulfonates (2923.30 and 2923.40), focusing solely on the broader group of phosphoaminolipids beyond these particular exclusions.

Within this broad category, further subdivisions exist to provide more granular classification. The subcategory 2923.20.10.00 is reserved for purified egg phospholipids that meet stringent U.S. Food and Drug Administration (FDA) pharmaceutical grade requirements and are specifically intended for use in intravenous fat emulsions. This highlights a critical distinction based on both purity standards and end-use application. The remaining phosphoaminolipids not meeting these specific criteria fall under the broader subcategory 2923.20.20, covering a wider array of commercial and industrial grades of lecithins and other phosphoaminolipids.