title: Dynamic isolation and unloading of target proteins by aptamer-modified microtransporters.
abstract: We describe here a new strategy for isolating target proteins from complex biological samples based on an aptamer-modified self-propelled microtube engine. For this purpose, a thiolated thrombin or a mixed thrombin-ATP aptamer (prehybridized with a thiolated short DNA) was coassembled with mercaptohexanol onto the gold surface of these microtube engines. The rapid movement of the aptamer-modified microtransporter resulted in highly selective and rapid capture of the target thrombin, with an effective discrimination against a large excess of nontarget proteins. Release of the captured thrombin can be triggered by the addition of ATP that can bind and displace the immobilized mixed thrombin-ATP aptamer in 20 min. The rapid loading and unloading abilities demonstrated by these selective microtransporters are illustrated in complex matrixes such as human serum and plasma. The new motion-driven protein isolation platform represents a new approach in bioanalytical chemistry based on active transport of proteins and offers considerable promise for diverse diagnostic applications.
authors: Department of Nanoengineering, University of California, San Diego, La Jolla, California 92093, USA.
authors: Jahir
authors: J
authors: Orozco
authors: Susana
authors: S
authors: Campuzano
authors: Daniel
authors: D
authors: Kagan
authors: Ming
authors: M
authors: Zhou
authors: Wei
authors: W
authors: Gao
authors: Joseph
authors: J
authors: Wang
mesh_terms: D000255:Adenosine Triphosphate / Q000737:chemistry; D052157:Aptamers, Nucleotide / Q000737:chemistry*; D001483:Base Sequence; D006046:Gold / Q000737:chemistry; D006801:Humans; D009841:Oligonucleotides / Q000737:chemistry; D052156:SELEX Aptamer Technique; D013438:Sulfhydryl Compounds / Q000737:chemistry; D013917:Thrombin / Q000032:analysis / Q000302:isolation & purification*
chemical_list: D052157:Aptamers, Nucleotide; D009841:Oligonucleotides; D013438:Sulfhydryl Compounds; D006046:Gold; D000255:Adenosine Triphosphate; D013917:Thrombin