Development of a low cost point-of-care device for rapid pathogen detection

Project Summary This project is focused on feasibility testing of a new device based on electromechanical signal transduction for the low cost$in electronicsoptics free and amplification freee gno PCRdetection of DNA RNA at ultralow concentrationThe device addresses the projected $B disease diagnostics market and is well suited for the detection of bacterial pathogens in body fluidsfood and water through the presence of specificS rRNA sequencesA compelling need persists for rapidminutescost effectivepoint of carePOCnucleic acidNAdetection devices for infectious disease diagnosticsThe investigators recently demonstrated detection of Escherichia coliEcoliS rRNA against afold background of Pseudomonas putida RNA at andltMandltCFUmLThis ultralow detection limit was achieved using a simple RNA extraction and hybridization protocol that is accomplished in andltmins at the lab benchIt is likely that an integrated microfluidic device eventually can be produced for pathogen detection in andltminsA key feature of the proposed device is the use of peptide nucleic acidPNAcapture probeswhich are uncharged polyamide analogs to NAs that share the same base chemistrySince the bead PNA conjugates are designed to be charge neutralthey do not exhibit electrophoretic movement in the presence of a DC electric fieldHoweverthe substantial negative charge acquired upon capture of a target NA sequence makes the hybridized conjugate mobileElectrophoresis of the bead PNA conjugate with hybridized target NA to the mouth of a smaller diameter glass pore causes a significant increase in pore resistancethereby resulting in a strongsustained drop in measured ionic currentNonspecifically bound NA is removed from the bead conjugate in the strong electric field in the pore mouth resulting in no sustained signalFurtherthe opposing electroosmotic flow through the glass pore sweeps bead PNA conjugates without hybridized target away from the pore mouthIn such a waythis simple conductometric device gives a highly selectivebinary response signaling the presence or absence of the target NAand associated pathogenThis project focuses onAimsDemonstration of selective detection of Ecoli in human urine against a background of normal flora at a statistical performance level competitive or better than existing commercial devices andDevelopment and testing of the inexpensivedevice associated electronics that are suitable for manufacturingSuccessful achievement of these Aims will substantiate the potential of the novel device for integration into a microfluidic system for detection of Neisseria gonorrhoeaea CDC top three public health threatand Chlamydia trachomatis in human urineFurtherthis project will illustrate the potential of the technology for development of generally applicableinexpensive POC devices for bacterial pathogens in body fluidsfood and water Project Narrative This project is focused on feasibility testing of a new device for the potentially rapidlow costdetection of bacterial pathogensThe device addresses the projected $B disease diagnostics market and is well suited for the detection of bacterial pathogens in body fluidsfood and water through the presence of specific nucleic acid sequencesSuccessful achievement of the project goals will substantiate the potential of the novel device for integration into a microfluidic system for detection of Neisseria gonorrhoeaea CDC top three public health threatand Chlamydia trachomatis in human urine