Antibody-drug conjugates (ADCs) are antibodies linked to one or more drug molecules. Some are being investigated as the cytotoxic component of antibody-drug conjugates. Antibody-drug conjugates (ADCs) comprise an antibody, drug and a linker between them. MDMA and metabolites are primarily excreted as conjugates, such as sulfates and glucuronides. Estrone is excreted in urine in the form of estrogen conjugates such as estrone sulfate. "Antibody-drug conjugates (ADC)" constitute a combination between small and big molecules. Estradiol is excreted in the form of glucuronide and sulfate estrogen conjugates in urine. Estrogens are excreted primarily by the kidneys as conjugates via the urine. The transformation of estradiol into estrone and estrogen conjugates is reversible. In feces, excretion is about 17% glucuronide conjugates, 20% sulfate conjugates, and 33% unconjugated. Tigecycline is metabolized through glucuronidation into glucuronide conjugates and "N"-acetyl-9-aminominocycline metabolite. After phase II reactions, the xenobiotic conjugates may be further metabolized. There are several different proteases which can remove NEDD8 from protein conjugates. Probody's conjugates against CD71 (transferrin receptor 1). Glutathione conjugates to NAPQI, and the resulting ensemble is excreted.