A novel and unconventional approach to impedance microbiology (IM) has been under investigation. In our approach, solution resistance variations will be generated from bacteriophage (phage) lyses of host cell and the consequent release of endoplasmic material. Phages are selective to their host and amplify inside viable cells, thus providing the mean for selective detection of only viable bacteria target. To sensitively detect the lysis, low conductive growth media have been developed. A microchip has been fabricated to perform the analysis. The microchip is made of two bare gold electrodes and PDMS microchamber of 36 nL volume. Escherichia coli and phages T4 have been used as case study. Proof-of-principle experiments are here presented. The method has a detection limit slightly below 100 CFU/mL. The phages has been previously immobilised on paramagnetic nanobeads and the whole method has the potential for integrating sample preparation with a potential detection limit below 1 CFU/chamber and assay time of 1 hour.
An impedance microbiology microsystem and anti-Escherichia coli functionalized paramagnetic beads for system detection probability
Mortari, Alessia;Adami, Andrea;Collini, Cristian;Lorenzelli, Leandro
2014-01-01
Abstract
A novel and unconventional approach to impedance microbiology (IM) has been under investigation. In our approach, solution resistance variations will be generated from bacteriophage (phage) lyses of host cell and the consequent release of endoplasmic material. Phages are selective to their host and amplify inside viable cells, thus providing the mean for selective detection of only viable bacteria target. To sensitively detect the lysis, low conductive growth media have been developed. A microchip has been fabricated to perform the analysis. The microchip is made of two bare gold electrodes and PDMS microchamber of 36 nL volume. Escherichia coli and phages T4 have been used as case study. Proof-of-principle experiments are here presented. The method has a detection limit slightly below 100 CFU/mL. The phages has been previously immobilised on paramagnetic nanobeads and the whole method has the potential for integrating sample preparation with a potential detection limit below 1 CFU/chamber and assay time of 1 hour.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.