Jennings used IR scattering to confirm the size (0.65mm x 1.35mm) and weight (0.17pg) of E.Coli. Now imaging of living cells on PDMS with a motorized stage fluorescence microscope, bacterial colonies on agar and silane-silica by SEM and biofilms and E.coli and S.Aureus growth in a petri dish using confocal microscope is possible, but with modest time (Dt) and spatial (Dx-Dy-Dz) resolution and in the case of SEM, unrealistic bioassay conditions. The authors have explored traditional bioassays of the activity and photoactivity of biomimetic nanomaterials based on Portobello mushroom spores (PMS) at inhibiting the growth of Eschericia coli, Staphylococcus aureus, Asperillus and Candide. Antibacterial activity was determined in duplicate using Mueller Hinton agar. The plates were incubated for 24 h at 309K, under aerobic conditions. The diameter of the zone of inhibition was measured in mm; tests were performed in duplicate. TiOx/PMS, Ag-TiOx/PMS, Au-TiOx/PMS and Ag/PMS were active in inhibition towards Eschericia coli and Staphylococcus aureus, but Au/PMS was not active (suggesting a strong Au-PMS interaction). TiOx/PMS, Ag/PMS and Ag-TiOx/PMS were equally active in an antibacterial and an antifungal sense when tested against Asperillus and Candide. We report on the process of fine-tuning these antibacterial properties, progress on making these nanomaterials optically self-indicating and movement towards optical control of their antibacterial activity. The future of such green bio-nanomaterials is strong. Here we report on the results of high-speed optical profiling that may provide a rapid and accurate bioassay at the patient-clinician interface and in the antibiotic drug discovery forums, providing a high-throughput screening route to measuring, understanding and then overcoming microbial resistance.

Novel, real-time analysis of nanomaterial inhibition of E. coli

253rd National Meeting (2017)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.