Journal: ACS Sensors

Article Title: Real-Time Respiration Changes as a Viability Indicator for Rapid Antibiotic Susceptibility Testing in a Microfluidic Chamber Array

doi: 10.1021/acssensors.1c00020

Figure Lengend Snippet: Characterization of the AST platform using the quality control strain. (A) Kinetic measurements of cell viability via oxygen-sensing nanoprobes immobilized in the agarose gel matrix. Comparison between control without antibiotic (no ATB) supplement E. coli ATCC 25922 culture (red, n = 15), and cultivation in the presence of ciprofloxacin at three different concentrations: 0.25 MIC ref , 1 MIC ref , and 4 MIC ref (green; numbers of analyzed chambers: n = 15, 24, 66, and 42, respectively). (B) Figures of the individual chambers show the bacterial morphology at the end of the measurement for each concentration of ciprofloxacin, MIC ref = 0.008 μg mL –1 . Scale bars: 100 μm. Temperature: 37 °C; MHB II, cation-adjusted medium and an initial OD 600 of 0.02 were maintained in all experiments. Error bars represent the standard deviations.

Article Snippet: To characterize the system, we first performed AST using the fully susceptible quality control E. coli strain ATCC 25922.

Techniques: Control, Agarose Gel Electrophoresis, Comparison, Concentration Assay

Journal: ACS Sensors

Article Title: Real-Time Respiration Changes as a Viability Indicator for Rapid Antibiotic Susceptibility Testing in a Microfluidic Chamber Array

doi: 10.1021/acssensors.1c00020

Figure Lengend Snippet: Validation of the AST platform using quality control strains. (A) Comparison between control (no ATB) E. coli ATCC 25922 culture (red, n = 56) and cultivation in the presence of amoxicillin (yellow, n = 71), meropenem (blue, n = 76), and ciprofloxacin (green, n = 42) at a concentration 4 times greater than MIC ref (4 μg mL –1 for amoxicillin, 0.016 μg mL –1 for meropenem, and 0.008 μg mL –1 for ciprofloxacin). (B) Comparison between control (no ATB) E. coli ATCC 35218 culture (red, n = 74) and cultivation in the presence of meropenem (blue, n = 48), amoxicillin (yellow, (4), n = 43), and ciprofloxacin (green, n = 36) at a concentration 4 time greater than MIC ref (0.016 μg mL –1 for meropenem, 4 μg mL –1 for amoxicillin, and 0.008 μg mL –1 for ciprofloxacin) together with amoxicillin (yellow, (25), n = 55), supplied at a concentration 25 times greater than MIC ref . (C) Detailed micrographs from selected chambers after 225 min of cultivation showing the morphological difference between the susceptible (ATCC 25922) and resistant (ATCC 35218) E. coli strain in the presence of amoxicillin supplied at a concentration 4 times greater than MIC ref for amoxicillin. Scale bars: 50 μm. Temperature: 37 °C; MHB II, cation-adjusted medium and an initial OD 600 of 0.02 were maintained in all experiments. Error bars represent the standard deviations. Here, n represents the number of analyzed chambers.

Article Snippet: To characterize the system, we first performed AST using the fully susceptible quality control E. coli strain ATCC 25922.

Techniques: Biomarker Discovery, Control, Comparison, Concentration Assay

Journal: ACS Sensors

Article Title: Real-Time Respiration Changes as a Viability Indicator for Rapid Antibiotic Susceptibility Testing in a Microfluidic Chamber Array

doi: 10.1021/acssensors.1c00020

Figure Lengend Snippet: Validation of the AST platform using a clinical isolate. Kinetic cell viability measurements via oxygen-sensing nanoprobes of the E. coli clinical isolate. Comparison between the standard bacterial culture without antibiotics (red, n = 29) and cultivation in the presence of amoxicillin (yellow, n = 48), meropenem (blue, n = 33), and ciprofloxacin (green, n = 47) at concentrations 4 times greater than reference MIC ref for E. coli . Corresponding bright-field micrographs show the bacterial morphology at the end of the assay, after 5 h of incubation. Inoculation was performed at an OD 600 of 0.02 (20 μL). Temperature: 37 °C, MHB II, cation-adjusted. Error bars represent the standard deviations. Here, n represents the number of analyzed chambers. Scale bars: 50 μm.

Article Snippet: To characterize the system, we first performed AST using the fully susceptible quality control E. coli strain ATCC 25922.

Techniques: Biomarker Discovery, Comparison, Incubation