Enrichment and Detection of <i>Escherichia coli</i> O157:H7 from Water Samples Using an Antibody Modified Microfluidic Chip

A novel rapid method for bacterial differentiation is explored based on the specific adhesion pattern of bacterial strains to tunable polymer surfaces. Different types of counter ions were used to electrochemically fabricate dissimilar polypyrrole (PPy) films with diverse physicochemical properties such as hydrophobicity, thickness and roughness. These were then modulated into three different oxidation states in each case. The dissimilar sets of conducting polymers were Principal Component Analysis showed that each strain of bacteria had its own specific adhesion pattern. Hence, they could be discriminated by this simple, label-free method. , based on tunable polymer arrays combined with pattern recognition.

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“…Cell gene expression and its phenotypes in the same microorganism differ in these two situations [23,24].…”

Section: Introductionmentioning

confidence: 99%

Tunable conjugated polymers for bacterial differentiation

Golabi

Turner

Jager

2016

Sensors and Actuators B: Chemical

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“…Currently used techniques include dielectrophoresis, 3,4 antibody modied surfaces, 5,6 acoustophoresis, 7 micropillar sieving, 8 the use of magnetic beads 9,10 or electrophoretic transport. 11 For the extraction of nucleic acids, usually specic protocols or kits depending on the biological sample and medium are used.…”

Section: Introductionmentioning

confidence: 99%

A lab-on-a-chip for preconcentration of bacteria and nucleic acid extraction

et al. 2018

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aTo improve detection sensitivity, molecular diagnostics require preconcentration of low concentrated samples followed by rapid nucleic acid extraction. This is usually achieved by multiple centrifugation, lysis and purification steps, for instance, using chemical reagents, spin columns or magnetic beads.These require extensive infrastructure as well as time consuming manual handling steps and are thus not suitable for point of care testing (POCT). To overcome these challenges, we developed a microfluidic chip combining free-flow electrophoretic (FFE) preconcentration (1 ml down to 5 ml) and thermoelectric lysis of bacteria as well as purification of nucleic acids by gel-electrophoresis. The integration of these techniques in a single chip is unique and enables fast, easy and space-saving sample pretreatment without the need for laboratory facilities, making it ideal for the integration into small POCT devices. A preconcentration efficiency of nearly 100% and a lysis/gel-electrophoresis efficiency of about 65% were achieved for the detection of E. coli. The genetic material was analyzed by RT-qPCR targeting the superfolder Green Fluorescent Protein (sfGFP) transcripts to quantify mRNA recovery and qPCR to determine DNA background.

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“…A well-established application is the separation of WBCs and RBCs in whole blood [6][7][8][9]. Bench-top filtration concepts using fibrous membranes (nitrocellulose [7], polycarbonate [8,10], polyacrylamide [11]) can be simply down-scaled and implemented into microdevices. In such devices, whole blood flows perpendicularly to the membrane comprising a magnitude of pores of precisely controlled size, which allows the passage of cells smaller than a critical size and retains their larger counterparts.…”

Section: Filtrationmentioning

confidence: 99%