Biomolecular motors, such as kinesin, have been used to shuttle a range of biological and synthetic cargo in microfluidic architectures. A critical gap in this technology is the ability to controllably link macromolecular cargo on microtubule (MT) shuttles without forming extraneous byproducts that may potentially limit their application. Here we present a generalized approach for functionalizing MTs with antibodies in which covalent bonds are formed between the carbohydrate in F-c region of polyclonal antibodies and the positively charged amino acids on the MT surface using the crosslinker succinimidyl 4-hydrazidoterephthalate hydrochloride (SHTH). Antibody-functionalized MTs (Ab-MTs) produced through this approach maintained motility characteristics and antigenic selectivity, and did not produce undesirable byproducts common to other approaches. We also demonstrate and characterize the application of these Ab-MTs for capturing and transporting bacterial and viral antigens. While this approach cannot be applied to monoclonal antibodies, which lack a carbohydrate moiety, it may be used for selectively functionalizing MT shuttles with a variety of carbohydrate-containing cargoes. Biotechnol. Bioeng. 2009; 104: 1182-1188. (C) 2009 Wiley Periodicals, Inc.