Rapid micromotor-based naked-eye immunoassay.
A dynamic micromotor-based immunoassay, exemplified by cortisol detection, based on the use of tubular micromotors functionalized with a specific antibody is described. The use of antibody-functionalized micromotors offers huge acceleration of both direct and competitive cortisol immunoassays, along with greatly enhanced sensitivity of direct and competitive immunoassays. The dramatically improved speed and sensitivity reflect the greatly increased likelihood of antibody-cortisol contacts and fluid mixing associated with the dynamic movement of these microtube motors and corresponding bubble generation that lead to a highly efficient and rapid recognition process. Rapid naked-eye detection of cortisol in the sample is achieved in connection to use of horseradish peroxidase (HRP) tag and TMB/H2O2system. Key parameters of the competitive immunoassay (e.g., incubation time and reaction volume) were optimized. This fast visual micromotor-based sensing approach enables "on the move" specific detection of the target cortisol down to 0.1μgmL-1in just 2min, using ultrasmall (50µL) sample volumes.
Department of Nanoengineering,, University of California, La Jolla, San Diego, CA 92093, United States.
Berta Esteban-Fernández
BE
de Ávila
Department of Nanoengineering,, University of California, La Jolla, San Diego, CA 92093, United States; Department of Chemistry, University of Rome, Tor Vergata,, Via della Ricerca Scientifica, 00133 Rome, Italy.
Mingjiao
M
Zhao
Department of Analytical Chemistry, Complutense University of Madrid, E-28040 Madrid, Spain.
Susana
S
Campuzano
Department of Chemistry, University of Rome, Tor Vergata,, Via della Ricerca Scientifica, 00133 Rome, Italy.
Francesco
F
Ricci
Department of Analytical Chemistry, Complutense University of Madrid, E-28040 Madrid, Spain.
José M
JM
Pingarrón
Department of Nanoengineering,, University of California, La Jolla, San Diego, CA 92093, United States; Department of Analytical Chemistry, Complutense University of Madrid, E-28040 Madrid, Spain; Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, 64100 Teramo, Italy. Electronic address: mmascini@unite.it.
Marcello
M
Mascini
Department of Nanoengineering,, University of California, La Jolla, San Diego, CA 92093, United States. Electronic address: josephwang@ucsd.edu.
Joseph
J
Wang
D000906:Antibodies / Q000737:chemistry* / Q000378:metabolism; D003124:Colorimetry; D006735:Horseradish Peroxidase / Q000737:chemistry*; D006801:Humans; D006854:Hydrocortisone / Q000032:analysis* / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000737:chemistry; D007118:Immunoassay / Q000379:methods*
D000906:Antibodies; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase; D006854:Hydrocortisone
Antibody; Cortisol; Micromotor; Naked-eye detection; Real-time sensing