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Title 21

Displaying title 21, up to date as of 7/16/2026. Title 21 was last amended 7/09/2026.
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Title 21Food and DrugsPart / Section
Chapter IFood and Drug Administration, Department of Health and Human Services1 – 1299
Subchapter HMedical Devices800 – 898
Part 866Immunology and Microbiology Devices866.1 – 866.6110
Subpart FImmunological Test Systems866.5040 – 866.5980
§ 866.5040Albumin immunological test system.
§ 866.5060Prealbumin immunological test system.
§ 866.5065Human allotypic marker immunological test system.
§ 866.5080Alpha-1-antichymotrypsin immunological test system.
§ 866.5090Antimitochondrial antibody immunological test system.
§ 866.5100Antinuclear antibody immunological test system.
§ 866.5110Antiparietal antibody immunological test system.
§ 866.5120Antismooth muscle antibody immunological test system.
§ 866.5130Alpha-1-antitrypsin immunological test system.
§ 866.5150Bence-Jones proteins immunological test system.
§ 866.5160Beta-globulin immunological test system.
§ 866.5170Breast milk immunological test system.
§ 866.5180Fecal calprotectin immunological test system.
§ 866.5200Carbonic anhydrase B and C immunological test system.
§ 866.5210Ceruloplasmin immunological test system.
§ 866.5220Cohn fraction II immunological test system.
§ 866.5230Colostrum immunological test system.
§ 866.5240Complement components immunological test system.
§ 866.5250Complement C1 inhibitor (inactivator) immunological test system.
§ 866.5260Complement C3b inactivator immunological test system.
§ 866.5270C-reactive protein immunological test system.
§ 866.5320Properdin factor B immunological test system.
§ 866.5330Factor XIII, A, S, immunological test system.
§ 866.5340Ferritin immunological test system.
§ 866.5350Fibrinopeptide A immunological test system.
§ 866.5360Cohn fraction IV immunological test system.
§ 866.5370Cohn fraction V immunological test system.
§ 866.5380Free secretory component immunological test system.
§ 866.5400Alpha-globulin immunological test system.
§ 866.5420Alpha-1-glycoproteins immunological test system.
§ 866.5425Alpha-2-glycoproteins immunological test system.
§ 866.5430Beta-2-glycoprotein I immunological test system.
§ 866.5440Beta-2-glycoprotein III immunological test system.
§ 866.5460Haptoglobin immunological test system.
§ 866.5470Hemoglobin immunological test system.
§ 866.5490Hemopexin immunological test system.
§ 866.5500Hypersensitivity pneumonitis immunological test system.
§ 866.5510Immunoglobulins A, G, M, D, and E immunological test system.
§ 866.5520Immunoglobulin G (Fab fragment specific) immunological test system.
§ 866.5530Immunoglobulin G (Fc fragment specific) immunological test system.
§ 866.5540Immunoglobulin G (Fd fragment specific) immunological test system.
§ 866.5550Immunoglobulin (light chain specific) immunological test system.
§ 866.5560Lactic dehydrogenase immunological test system.
§ 866.5570Lactoferrin immunological test system.
§ 866.5580Alpha-1-lipoprotein immunological test system.
§ 866.5590Lipoprotein X immunological test system.
§ 866.5600Low-density lipoprotein immunological test system.
§ 866.5620Alpha-2-macroglobulin immunological test system.
§ 866.5630Beta-2-microglobulin immunological test system.
§ 866.5640Infectious mononucleosis immunological test system.
§ 866.5660Multiple autoantibodies immunological test system.
§ 866.5665Aquaporin-4 autoantibody immunological test system.
§ 866.5670Zinc transporter 8 autoantibody immunological test system.
§ 866.5680Myoglobin immunological test system.
§ 866.5700Whole human plasma or serum immunological test system.
§ 866.5715Plasminogen immunological test system.
§ 866.5735Prothrombin immunological test system.
§ 866.5750Radioallergosorbent (RAST) immunological test system.
§ 866.5760Tryptase test system.
§ 866.5765Retinol-binding protein immunological test system.
§ 866.5775Rheumatoid factor immunological test system.
§ 866.5780Anti-phospholipase A2 receptor immunological test system.
§ 866.5785Anti-Saccharomyces cerevisiae (S. cerevisiae) antibody (ASCA) test systems.
§ 866.5800Seminal fluid (sperm) immunological test system.
§ 866.5820Systemic lupus erythematosus immunological test system.
§ 866.5830Brain trauma assessment test.
§ 866.5840Alzheimer's disease pathology assessment test.
§ 866.5860Total spinal fluid immunological test system.
§ 866.5870Thyroid autoantibody immunological test system.
§ 866.5880Transferrin immunological test system.
§ 866.5890Inter-alpha trypsin inhibitor immunological test system.
§ 866.5900Cystic fibrosis transmembrane conductance regulator (CFTR) gene mutation detection system.
§ 866.5910Quality control material for cystic fibrosis nucleic acid assays.
§ 866.5920Postnatal chromosomal copy number variation detection system.
§ 866.5930Newborn screening test for severe combined immunodeficiency disorder (SCID).
§ 866.5940Autosomal recessive carrier screening gene mutation detection system.
§ 866.5950Genetic health risk assessment system.
§ 866.5960Human leukocyte antigen typing companion diagnostic test.
§ 866.5970Inherited nucleotide repeat disorder DNA test.
§ 866.5980Spinal Muscular Atrophy newborn screening test system.