Development of a High-Throughput Minimum Inhibitory Concentration (HT-MIC) Testing Workflow

The roots of the minimum inhibitory concentration (MIC) determination go back to the early 1900s. Since then, the test has undergone modifications and advancements in an effort to increase its dependability and accuracy. Although biological investigations use an ever-increasing number of samples, complicated processes and human error sometimes result in poor data quality, which makes it challenging to replicate scientific conclusions. The automation of the few manual steps using protocols decipherable by machine can ease some of the procedural difficulties. Originally relying on manual pipetting and human vision to determine the results, modern broth dilution MIC testing procedures have incorporated microplate readers to enhance sample analysis. However, current MIC testing procedures are unable to simultaneously evaluate a large number of samples efficiently. Here, we have created a workflow using the Opentrons OT-2 robot to enable high-throughput MIC testing. We have further optimized the analysis by incorporating Python programming for MIC assignment to streamline the automation. In this workflow, we performed MIC tests on four different strains, three replicates per strain, and analyzed a total of 1,152 wells. Comparing our our workflow to a conventional plate MIC procedure, we find that the HT-MIC method is 630% faster while simulataneously boasting a 100% accuracy. Our high-throughput MIC workflow can be applied in both academic and clinical settings since it is faster, more efficient, and more accurate than many conventional methods.