Show simple item record

dc.contributor.advisorGhodssi, Rezaen_US
dc.contributor.authorZang, Fahengen_US
dc.date.accessioned2016-09-07T05:32:41Z
dc.date.available2016-09-07T05:32:41Z
dc.date.issued2016en_US
dc.identifierhttps://doi.org/10.13016/M2RR5Z
dc.identifier.urihttp://hdl.handle.net/1903/18645
dc.description.abstractRapid, sensitive and selective detection of chemical hazards and biological pathogens has shown growing importance in the fields of homeland security, public safety and personal health. In the past two decades, efforts have been focusing on performing point-of-care chemical and biological detections using miniaturized biosensors. These sensors convert target molecule binding events into measurable electrical signals for quantifying target molecule concentration. However, the low receptor density and the use of complex surface chemistry in receptors immobilization on transducers are common bottlenecks in the current biosensor development, adding to the cost, complexity and time. This dissertation presents the development of selective macromolecular Tobacco mosaic virus-like particle (TMV VLP) biosensing receptor, and the microsystem integration of VLPs in microfabricated electrochemical biosensors for rapid and performance-enhanced chemical and biological sensing. Two constructs of VLPs carrying different receptor peptides targeting at 2,4,6-trinitrotoluene (TNT) explosive or anti-FLAG antibody are successfully bioengineered. The VLP-based TNT electrochemical sensor utilizes unique diffusion modulation method enabled by biological binding between target TNT and receptor VLP. The method avoids the influence from any interfering species and environmental background signals, making it extremely suitable for directly quantifying the TNT level in a sample. It is also a rapid method that does not need any sensor surface functionalization process. For antibody sensing, the VLPs carrying both antibody binding peptides and cysteine residues are assembled onto the gold electrodes of an impedance microsensor. With two-phase immunoassays, the VLP-based impedance sensor is able to quantify antibody concentrations down to 9.1 ng/mL. A capillary microfluidics and impedance sensor integrated microsystem is developed to further accelerate the process of VLP assembly on sensors and improve the sensitivity. Open channel capillary micropumps and stop-valves facilitate localized and evaporation-assisted VLP assembly on sensor electrodes within 6 minutes. The VLP-functionalized impedance sensor is capable of label-free sensing of antibodies with the detection limit of 8.8 ng/mL within 5 minutes after sensor functionalization, demonstrating great potential of VLP-based sensors for rapid and on-demand chemical and biological sensing.en_US
dc.language.isoenen_US
dc.titleIntegration of virus-like particle macromolecular bioreceptors in electrochemical biosensorsen_US
dc.typeDissertationen_US
dc.contributor.publisherDigital Repository at the University of Marylanden_US
dc.contributor.publisherUniversity of Maryland (College Park, Md.)en_US
dc.contributor.departmentElectrical Engineeringen_US
dc.subject.pqcontrolledElectrical engineeringen_US
dc.subject.pqcontrolledBiomedical engineeringen_US
dc.subject.pqcontrolledMechanical engineeringen_US
dc.subject.pquncontrolledbiosensorsen_US
dc.subject.pquncontrolledcapillary microfluidicsen_US
dc.subject.pquncontrolledimpedanceen_US
dc.subject.pquncontrolledmicrofluidicsen_US
dc.subject.pquncontrolledmicrosystemsen_US
dc.subject.pquncontrolledvirus-like particlesen_US


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record