Evaluation and validation of Biolog OmniLog® system for antibacterial activity assays.
Cristina D CruzP EstevePäivi TammelaPublished in: Letters in applied microbiology (2021)
Minimal inhibitory concentration of antimicrobials, determined by the broth microdilution method, requires visual assessment or absorbance measurement using a spectrophotometer. Both procedures are usually performed manually, requiring the presence of an operator to assess the plates at specific time point. To increase the throughput of antimicrobial susceptibility testing, and concurrently convert into an automatic assay, the Biolog OmniLog® system was validated for a new, label-free application using standard 96-well microplates. OmniLog was evaluated for its signal strength to ensure that the signal intensity, detected and measured by the system's camera, was satisfactory. Variability due to the plate location inside the OmniLog incubator, as well as variation between wells, was investigated. Then the system was validated by determining the minimal inhibitory concentration of ciprofloxacin, piperacillin and linezolid against a selected Gram-negative and Gram-positive strains. No significant difference was observed in relation to position of the plates within the system. Plate edge effects were noticeable, thus the edge wells were not included in further experiments. Minimal inhibitory concentration results were comparable to those obtained by conventional protocol as well as to values defined by the Clinical Laboratory Standards Institute or published in the literature.
Keyphrases
- gram negative
- multidrug resistant
- label free
- high throughput
- randomized controlled trial
- systematic review
- escherichia coli
- pseudomonas aeruginosa
- deep learning
- machine learning
- high speed
- convolutional neural network
- methicillin resistant staphylococcus aureus
- atomic force microscopy
- cystic fibrosis
- staphylococcus aureus
- single molecule
- meta analyses