8 February 2018 Unraveling bacterial networks and their antimicrobial susceptibility on silicon microarchitectures using intrinsic phase-shift spectroscopy
Author Affiliations +
Abstract
We have developed a rapid phenotypic antimicrobial susceptibility testing (AST) in which photonic 2D silicon microarrays are employed as both the optical transducer element and as a preferable solid−liquid interface for bacterial colonization. We harness the intrinsic ability of the micro-architectures to relay optical phase-shift reflectometric interference spectroscopic measurements (termed PRISM) and incorporate it into a platform for culture-free, label-free tracking of bacterial accumulation, proliferation, and death. This assay employs microfluidic channels interfaced with PRISM chips and is carried out in a two-stage process, namely bacteria seeding and antibiotic incubation. Bacteria proliferation within the microtopologies results in an increase in refractive index of the medium, yielding an increase in optical path difference, while cell death or bacteriostatic activity results in decreasing or unchanged values. The optical responses of bacteria to various concentrations of relevant antibiotics have been tracked in real time, allowing for accurate determination of the minimum inhibitory concentration (MIC) values within 2-3 hours. We further extended this work to analyze antibiotic susceptibilities of clinical isolates and direct urine samples derived from patients at neighboring hospitals in newly designed, disposable microfluidic devices. This has opened the door to the observation of unique bacterial behaviors, as we can evaluate bacterial adhesion, growth, and antibiotic resistance on different microarchitectures, different surface chemistries, and even different strains. Motility, charge, and biofilm abilities have been explored for their effect of bacterial adhesion to the microstructures as we further develop our method of rapid, label-free AST for full clinical application.
Conference Presentation
© (2018) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Heidi Leonard, Heidi Leonard, Liran Holtzman, Liran Holtzman, Yuri Haimov, Yuri Haimov, Daniel Weizman, Daniel Weizman, Yechezkel Kashi, Yechezkel Kashi, Ofer Nativ, Ofer Nativ, Sarel Halachmi, Sarel Halachmi, Ester Segal, Ester Segal, } "Unraveling bacterial networks and their antimicrobial susceptibility on silicon microarchitectures using intrinsic phase-shift spectroscopy", Proc. SPIE 10479, Light-Based Diagnosis and Treatment of Infectious Diseases, 1047907 (8 February 2018); doi: 10.1117/12.2287655; https://doi.org/10.1117/12.2287655
PROCEEDINGS
7 PAGES + PRESENTATION

SHARE
Back to Top