title: Rapid Bead-Based Antimicrobial Susceptibility Testing by Optical Diffusometry.
abstract: This study combined optical diffusometry and bead-based immunoassays to develop a novel technique for quantifying the growth of specific microorganisms and achieving rapid AST. Diffusivity rises when live bacteria attach to particles, resulting in additional energy from motile microorganisms. However, when UV-sterilized (dead) bacteria attach to particles, diffusivity declines. The experimental data are consistent with the theoretical model predicted according to the equivalent volume diameter. Using this diffusometric platform, the susceptibility of Pseudomonas aeruginosa to the antibiotic gentamicin was tested. The result suggests that the proliferation of bacteria is effectively controlled by gentamicin. This study demonstrated a sensitive (one bacterium on single particles) and time-saving (within 2 h) platform with a small sample volume (~0.5 μL) and a low initial bacteria count (50 CFU per droplet ~ 105 CFU/mL) for quantifying the growth of microorganisms depending on Brownian motion. The technique can be applied further to other bacterial strains and increase the success of treatments against infectious diseases in the near future.
authors: Department of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan.
authors: Chih-Yao
authors: CY
authors: Chung
authors: Department of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan.|Division of Urology, Department of Surgery, Chi Mei Medical Center, Tainan, Taiwan.
authors: Jhih-Cheng
authors: JC
authors: Wang
authors: Department of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan.|Medical Device Innovation Center, National Cheng Kung University, Tainan, Taiwan.
authors: Han-Sheng
authors: HS
authors: Chuang
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D058491:Bacterial Load; D002455:Cell Division; D004351:Drug Resistance; D005839:Gentamicins / Q000494:pharmacology*; D007118:Immunoassay / Q000379:methods*; D008826:Microbial Sensitivity Tests / Q000379:methods*; D008855:Microscopy, Electron, Scanning; D008856:Microscopy, Fluorescence; D008863:Microspheres; D009038:Motion; D010316:Particle Size; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000254:growth & development / Q000502:physiology; D055471:Thermal Diffusion; D013997:Time Factors; D014783:Viscosity
chemical_list: D000900:Anti-Bacterial Agents; D005839:Gentamicins