MJ Gray,1,2 F Liang,1,2 DJ Browne,1 RT Barnard,2 GR Hill,1,3 KA Markey,1, 3SR Corrie4*


1Bone Marrow Transplantation Laboratory, QIMR Berghofer Medical Research Institute

2School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Australia

3Department of Haematology and Bone Marrow Transplantation, Royal Brisbane and Women’s Hospital, Brisbane, Australia

4Department of Chemical Engineering, Monash University, Melbourne, Australia


The infectious complications of therapy represent a significant source of morbidity and mortality for the 10, 000 Australians diagnosed with leukemia and lymphoma each year. Despite rapid advances in other areas of cancer care, clinicians are reliant on culture-based methods to diagnose severe bloodstream infection, which frequently take >12 hrs for gram/species identification and longer for antibiotic resistance information. We have developed a microsphere-PCR assay to distinguish between gram-positive and gram-negative organisms. Multiplexed PCR reactions are performed in the presence of primer-specific polymer beads encoded with a primer-specific fluorescent signature. In contrast to traditional PCR strategies, we measure the consumption of the primers required for DNA amplification rather than the amplified product itself. At the conclusion of the PCR, the samples are analysed by flow cytometry, allowing quantification of target DNA sequences.


The assay is both sensitive and specific for the most common Gram positive and Gram negative organisms encountered in local practice, and can correctly identify gram-status of bacteria spiked into healthy human blood. Here we will present the results from a proof-of-principle study, and highlight opportunities for nanotechnology in the management of bloodstream infections.




Biographic Details

Name: Simon Corrie

Title: Senior Lecturer

Affiliation, Country: Monash University, Australia

Phone: +613 9905 9621 E-mail: simon.corrie@monash.edu

Research interests: biosensors, bioassays, biomaterials


Hawken N201