Nanoparticle-mediated methods for antimicrobial susceptibility testing of bacteria
A method of testing bacterial cells for antimicrobial susceptibility includes preparing a suspension of the bacterial cells in a non-nutrient medium, mixing with the suspension an antimicrobial, a carbohydrate usable by the bacterial cells, metallic nanoparticles, and a lectin, and incubating the mixture while monitoring a parameter of the nanoparticles responsive to use of the carbohydrate by the bacterial cells. More broadly stated, the invention includes a method of testing an agent for its effect on cell metabolism by preparing a suspension of cells in a non-nutrient medium, mixing the suspension with the agent, adding a carbohydrate usable by the cells, metallic nanoparticles, and a lectin with binding specificity for the added carbohydrate, and monitoring a nanoparticle parameter responsive to the cells.
1. A method of testing bacterial cells for antimicrobial susceptibility, the method comprising:
mixing a suspension of bacterial cells in a non-nutrient medium with an antimicrobial and a carbohydrate usable by the bacterial cells;
adding iron oxide nanoparticles and a lectin to the mixture; and
monitoring a parameter associated with the nanoparticles responsive to use of the carbohydrate by the bacterial cells.
2. The method of claim 1 , wherein the antimicrobial comprises a pharmaceutical administrable to a human or animal patient.
3. The method of claim 1 , wherein the iron oxide nanoparticles nanoparticles comprise rod-shaped nanoparticles.
4. The method of claim 1 , wherein the lectin is conjugated to the surface of the iron oxide nanoparticles before adding.
5. The method of claim 1 , wherein the iron oxide nanoparticles further comprise a coating polymer which bears the lectin.
6. The method of claim 1 , wherein the iron oxide nanoparticles further comprise a coating of amino-silica bearing the lectin.
7. The method of claim 1 , wherein the iron oxide nanoparticles further comprise a coating polyacrylic acid polymer bearing the lectin.
8. The method of claim 1 , wherein the lectin has a high binding affinity for the carbohydrate.
9. The method of claim 1 , wherein the lectin comprises concanavalin A.
10. The method of claim 1 , wherein the parameter is monitored by nuclear magnetic resonance.
11. The method of claim 1 , wherein the parameter is monitored by the nuclear magnetic resonance T2 water relaxation time.
12. The method of claim 1 , wherein the magnetic relaxation parameter comprises an increase or a decrease in T2 water relaxation time by nuclear magnetic resonance.
13. The method of claim 1 , wherein the iron oxide nanoparticles are capable of causing an increase or a decrease in the T2 of water.