title: Highly sensitive immunosensor using a nanofluidic preconcentrator.
abstract: This paper presents a micro-/nanofluidic biochip for enhanced sensitivity of immunoassay. By using a protein preconcentrator based on nanofluidic filters, we greatly improve the binding kinetics of immunoassay. A shallow nanofluidic channel connecting two microchannels for ion-selective filter is etched on the glass surface and sealed by PDMS/Glass irreversible bonding treated with O2 plasma. Our device achieved a 10(5) fold increase in protein concentration with 12 minutes of preconcentration. For applying the preconcentrator to immunoassay, we fabricated a novel device with a thin layer of Au sputtered near the nanochannel to provide a substrate for antibody immobilization and a sensing area at the site of highly concentrated proteins. After increasing the concentration of antibody and target antigen by multiple sample preconcentration steps, the binding kinetics of immunoassay can be significantly improved.
authors.affiliation: Department of Electrical Engineering, National Taiwan University, Taiwan.
authors.forename: Ke-Pan
authors.initials: KP
authors.lastname: Liao
authors.forename: Kung-Bin
authors.initials: KB
authors.lastname: Sung
mesh_terms: D000818:Animals; D000906:Antibodies / Q000737:chemistry; D001665:Binding Sites; D002417:Cattle; D004867:Equipment Design; D006046:Gold / Q000737:chemistry; D007118:Immunoassay / Q000295:instrumentation*; D007477:Ions; D007700:Kinetics; D044085:Microfluidics / Q000295:instrumentation*; D036103:Nanotechnology / Q000295:instrumentation*; D011485:Protein Binding; D011506:Proteins / Q000032:analysis / Q000737:chemistry; D012680:Sensitivity and Specificity; D013997:Time Factors
chemical_list: D000906:Antibodies; D007477:Ions; D011506:Proteins; D006046:Gold