Mr. Gregory Blyskal
Dynal, Inc. 475 Northern Blvd. Great Neck, NY 11021

RE: Modification of New York Ruling Letter 860953; Tariff Classification of Diasorin Dynabeads M-450 Tosylactivated and Dynabeads M-280 Tosylactivated products

Dear Mr. Blyskal,

This is in regard to New York Ruling Letter (NY) 860953, issued to Dynal, Inc. (Dynal), dated March 38, 1991, regarding the classification under the Harmonized Tariff Schedule of the United States (HTSUS), of Dynabeads M-450 Tosylactivated (M-450 TOS) and Dynabeads M-280 Tosylactivated (M-280 TOS) products. Customs and Border Protection (CBP) classified the above-identified products under heading 3903, HTSUS, which provides for “Polymers of styrene, in primary forms”. We have reviewed NY 860953 and found it to be incorrect. For the reasons set forth below, we propose to modify that ruling.

Pursuant to section 625(c)(1), Tariff Act of 1930 (19 U.S.C. §1625(c)(1)), as amended by section 623 of Title VI, notice proposing to revoke NY 860953 was published on May 25, 2011, in Volume 45, Number 22, of the Customs Bulletin.  CBP received no comments in response to this notice.


In NY 860953, CBP described the products in the following manner:

The beads (both the M-450 and M-280) are polystyrene spheres that contain an iron oxide salt. The polystyrene bead acts as a solid phase for the attachment of antibodies. There are two groups of products as follows:

Group I types are uncoated beads which allow researchers to attach an antibody of their choice directly onto the bead: Dynabeads M-450 uncoated Dynabeads M-450 Tosylactivated Dynabeads M-280 Tosylactivated * * * In NY 860953, CBP classified M-280 TOS and M-450 TOS in heading 3903, HTSUS, specifically under subheading 3903.19.00, HTSUS, which provides for “Polymers of styrene, in primary forms: Polystyrene: Other”.

According to the product manual provided at , the M-450 TOS product is described in the following manner:

1.1 Intended Use Dynabeads M-450 Tosylactivated coupled with antibodies or other ligands provide a versatile tool for isolation of both cells and non-cell targets (e.g. proteins and other biomolecules). Their size makes them particularly suitable for stimulation and expansion of e.g. T cells (2,3,4,7). Cells can be directly isolated from any sample such as whole blood, bone marrow, mononuclear cell suspensions (MNC) or tissue digests. * * * 1.2 Principle of Coupling Dynabeads M-450 Tosylactivated provide reactive sulphonyl esters that can react covalently with proteins (e.g. antibodies) or other ligands containing primary amino or sulphydryl groups. No further activation is necessary. Dynabeads M-450 Tosylactivated will bind proteins physically and chemically with an increasing number of covalent bonds with higher temperature and pH. * * * 1.4 Description of Materials Dynabeads M-450 Tosylactivated are uniform, superparamagnetic polystyrene beads (4.5 µm diameter) with a surface suitable for physical and chemical binding of antibodies and other biomolecules. * * * 4. GENERAL INFORMATION * * * Warning And Limitations This product is for research use only. Not intended for any animal or human therapeutic or diagnostic use unless otherwise stated. * * *

According to the product manual provided at , the M-280 TOS product has a similar construction, except that the beads are smaller (2.8 µm diameter instead of 4.5 µm). In addition, the M-280 TOS product is recommended for Target Protein Isolation procedures and Immunoassy procedures, rather than Cell Isolation.


What is the proper classification of the Dynabeads M-280 Tosylactivated and Dynabeads M-450 Tosylactivated products under the HTSUS?


Classification of goods under the HTSUS is governed by the General Rules of Interpretation (GRI). GRI 1 provides that classification shall be determined according to the terms of the headings of the tariff schedule and any relative section or chapter notes. In the event that the goods cannot be classified solely on the basis of GRI 1, and if the headings and legal notes do not otherwise require, the remaining GRI may then be applied.

The 2011 HTSUS provisions at issue are as follows:

3822 Diagnostic or laboratory reagents on a backing and prepared diagnostic or laboratory reagents, whether or not on a backing, other than those of heading 3002 or 3006; certified reference materials: Diagnostic or laboratory reagents on a backing, prepared diagnostic or laboratory reagents, whether or not on a backing, other than those of heading 3002 or 3006: 3822.00.50 Other ------------------------------------------------------------------- 3903 Polymers of styrene, in primary forms: Polystyrene 3903.19.00 Other --------------------------------------------------------------------

Note 2(k) to Chapter 39, HTSUS, states, in pertinent part: “This chapter does not cover: … (k) Diagnostic or laboratory reagents on a backing of plastics (heading 3822); …”.

The Harmonized Commodity Description and Coding System Explanatory Notes (ENs), constitute the official interpretation of the Harmonized System at the international level. While neither legally binding nor dispositive, the EN provide a commentary on the scope of each heading of the HTSUS and are generally indicative of the proper interpretation of the headings. It is CBP’s practice to consult, whenever possible, the terms of the ENs when interpreting the HTSUS. See T.D. 89–80, 54 Fed. Reg. 35127, 35128 (August 23, 1989).

The EN to Heading 38.22 states, in pertinent part:

Prepared laboratory reagents include not only diagnostic reagents, but also other analytical reagents used for purposes other than detection or diagnosis.  Prepared diagnostic and laboratory reagents may be used in medical, veterinary, scientific or industrial laboratories, in hospitals, in industry, in the field or, in some cases, in the home. * * *

The instant merchandise, as imported, consists of three layers. The first two layers are a manufactured “bead,” which has a core of iron oxide salt encapsulated by a polystyrene polymer. The beads are manufactured in a special process, giving them two important characteristics. First, all the beads are the same size. This is a function of the emulsification process of the polystyrene polymerizing process. Second, the beads are magnetic. This is a function of the added iron oxide salt. These beads functions as the “backing.” The beads are then coated with a third layer, which is a polyurethane polymer. Finally, the hydroxyl groups of the polyurethane polymer are reacted with p-toluenesulfonyl chloride, which attaches sulfonyl ester groups to the hydroxyl groups of the polyurethane.

M-450 TOS is used in Cell Isolation procedures. M-280 TOS is used in Protein Purification and Immunoassay procedures. All of these procedures use a ligand (such as an antibody, protein, peptide, or glycoprotein) to isolate and separate a target molecule. However, the instant merchandise, as imported, cannot be used for either procedure. The end user must employ the Ligand Coupling Protocol as outlined in the product manuals. This process is a chemical reaction which removes the sulfonyl ester groups from the polyurethane layer and replaces them with the ligand chosen by the end user. Once this procedure is complete, the user has a new chemical substance which can be used for some other purpose, be it Cell Isolation, Protein Purification or Immunoassays.

A reagent is “a substance employed as a test to determine the presence of some other substance by means of the reaction which is produced. Now, any substance employed in chemical reactions.” The Compact Oxford English Dictionary, Second Edition (p. 271, 1991). Such substances are also called reactants. A reactant is defined as “a substance that is consumed in the course of a chemical reaction. It is sometimes known, especially in the older literature, as a reagent, but this term is better used in a more specialized sense as a test substance that is added to a system in order to bring about a reaction or to see whether a reaction occurs (e.g. an analytical reagent).” Compendium of Chemical Terminology, IUPAC Recommendations, Second Edition. (p. 342, 1997).

Typically, a reagent is mixed with another chemical, reacts with it, and is consumed in that reaction, creating a different set of chemicals. For instance, silver nitrate is a reagent used for the detection of certain halide ions (chloride, iodide, bromide), particularly for chloride. When clear silver nitrate and sodium chloride solutions are combined, the silver and chloride ions react with one another to form a silver chloride solid precipitate and a solution of sodium nitrate. Hence, the addition of silver nitrate to a clear sodium chloride solution allows one to detect the presence of chloride in the solution, because the white silver chloride precipitate could not have formed without its presence.

The instant merchandise meets the definition of “reagent.” Both are mixed with another chemical, specifically, the chosen ligand and buffer solutions. A chemical reaction occurs, wherein the sulfonyl ester groups attached to the polyurethane polymer are removed and replaced with the chosen ligand. The chemical composition of the polyurethane layer is changed. The reaction creates a different set of chemicals, usable for a new purpose. Therefore, the M-450 TOS and M-280 TOS products are properly classified under heading 3822, HTSUS, as “… prepared … laboratory reagents, whether or not on a backing …”.

New York Ruling (NY) 863359, dated May 24, 1991, considered four similar products, namely Dynabeads M-280 streptavidin, Dynabeads Oligo (dt)25, Dynabeads Template preparation kit and Dynabeads mRNA. All of these products use the same superparamagnetized polystyrene bead as the instant merchandise. However, they use a different coating. The Dynabeads M-280 streptavidin product is a bead coated with streptavidin, which is a protein used to capture biotin from a sample. This product is ready to use for numerous applications, including purification of proteins and nucleic acids, protein interaction studies, immunoprecipitation, immunoassays, phage display, biopanning, drug screening and cell isolation. The Dynabeads Oligo (dt) 25 product is a bead coated with oligonucleotides, which is a nucleic acid used to capture intact mRNA from a sample. The product is ready to use for the rapid isolation of highly purified, intact mRNA from eukaryotic total RNA or directly from crude extracts of cells, animal and plant tissues. The Dynabeads Template preparation kit is a package containing Dynabeads M-280 streptavidin and several buffer solutions. The Dynabeads mRNA purification kit is a package containing Dynabeads Oligo (dt)25 and several buffer solutions. These products are different from the instant merchandise, in that they do not have to go through the Coating Procedure. A chosen ligand has already been attached. However, they are similar in that the products coated with streptavidin and oligonucleotide form strong chemical bonds with their target molecule, changing their chemical composition. CBP classified them under heading 3822, HTSUS, as reagents, even though the reactions are reversible.

In Headquarters Ruling (HQ) 967094, dated May 11, 2006, CBP considered HyperD® products similar to the instant merchandise. The HyperD® products are composite materials in bead form consisting of a co-polymeric crosslinked network (hydrogel) distributed inside the pores of a rigid, mineral (mixture of sintered zirconium and calcium silicates) “ceramic” support (substrate). The substrate acts as a solid skeleton, while the hydrogel polymer governs the exchange mechanism for macromolecule or particle adsorption. The polymer provides a tridimensional network for the capture of separated molecules. Affinity ligands are chemically attached to the hydrogel polymers at one end, leaving the other end free to react with the targeted substance to form a complex or coordination compound with that substance. CBP held that these products were “separation media,” rather than reactants, and found that they were not classifiable under heading 3822, HTSUS.

Separation media are not reagents because there is no chemical reaction that consumes the reagent. Rather, the HyperD® products are used in “adsorption chromatography,” the “separation of a chemical mixture (gas or liquid) by passing it over an adsorbent bed which adsorbs different compounds at different rates.” “Adsorption” is defined as “the surface retention of solid, liquid, or gas molecules, atoms, or ions by a solid or liquid . . . .” McGraw-Hill Dictionary of Scientific and Technical Terms, Fifth Ed., Parker, Sybil P., ed. (1994, p. 38). While the EN’s specifically include a seemingly broad spectrum of reagents, including “other analytical reagents used for purposes other than detection or diagnosis,” separation media cannot be considered a reagent, analytical or otherwise, as explained above.

Chapter 39, HTSUS, does not cover laboratory reagents on a backing of plastics. See Note 2(k) to Chapter 39, HTSUS. As described above, the instant merchandise is a prepared laboratory reagent. In addition, it is on a backing of plastics, in the form of a polystyrene and polyurethane superparamagnetic bead. Therefore, the M-450 TOS and M-280 TOS products are precluded from classification under heading 3903, HTSUS.


By application of GRI 1, the Dynabeads M-450 and Dynabeads M-280 Tosylactivated products are properly classified under heading 3822, HTSUS, specifically under subheading 3822.00.50, HTSUS, which provides for “Diagnostic or laboratory reagents on a backing and prepared diagnostic or laboratory reagents, whether or not on a backing, other than those of heading 3002 or 3006; certified reference materials: Diagnostic or laboratory reagents on a backing, prepared diagnostic or laboratory reagents, whether or not on a backing, other than those of heading 3002 or 3006: Other”.

The general, column one duty rate is free. Duty rates are provided for your convenience and are subject to change.


NY 860953, dated March 28, 1991, is hereby MODIFIED in accordance with the above analysis.

In accordance with 19 U.S.C. §1625(c), this ruling will become effective 60 days after publication in the Customs Bulletin.


Myles B. Harmon, Director
Commercial and Trade Facilitation Division