Antibiotic Susceptibility Test with Surface-Enhanced Raman Scattering in a Microfluidic System
Journal
Analytical Chemistry
Journal Volume
91
Journal Issue
17
Pages
10988-10995
Date Issued
2019
Author(s)
Abstract
Antibiotic susceptibility test (AST) is essential in clinical diagnosis of serious bacterial infection, such as sepsis, while it typically takes 2-5 days for sample culture, antibiotic treatment, and reading result. Detecting metabolites secreted from bacteria with surface-enhanced Raman scattering (SERS) enables rapid determination of antibiotic susceptibility, reducing the AST time to 1-2 days. However, it still requires 1 day of culture time to obtain sufficient quantity of bacteria for sample washing, bacterial extraction, and antibiotic treatment. Additionally, the whole procedure, manually performed in open environment, often suffers from contamination and human error. To address the above problems, a microfluidic system integrating membrane filtration and the SERS-active substrate (MF-SERS) was developed to perform on-chip bacterial enrichment, metabolite collection, and in situ SERS measurements for antibiotic susceptibility test. Using Escherichia coli as the prototype bacterium, the lowest SERS detection limit of bacterial concentration of the MF-SERS system is 103 CFU/mL, which is 4 orders of magnitude lower than that using centrifugation-purification procedure, significantly shortening the bacterial culture time. The bacteria and secreted metabolites are enclosed during bacterial trapping, metabolite filtration, and SERS detection, thus minimizing possible contamination and human errors. Finally, the successful demonstration of AST on E. coli with a concentration of 103 CFU/mL is presented. Overall, the MF-SERS system with a miniature size and well-confined microenvironment allows the integration of multiple bacteria processes for bacterial enrichment, culture, and determination of AST. Copyright © 2019 American Chemical Society.
SDGs
Other Subjects
Antibiotics; Biomolecules; Diagnosis; Errors; Escherichia coli; Fluidic devices; Metabolites; Microfiltration; Microfluidics; Raman scattering; Substrates; Surface testing; Antibiotic susceptibilities; Antibiotic susceptibility tests; Antibiotic treatment; Membrane filtrations; Micro fluidic system; Purification procedures; SERS-active substrates; Surface enhanced Raman Scattering (SERS); Surface scattering
Type
journal article