Our article "Cell-on-Hydrogel Platform Made of Agar and Alginate for Rapid, Low-cost, Multidime
Antimicrobial resistance makes the treatment difficult, costly, or even impossible; it is alerted by WHO as a major threat to public health, and causing enormous financial loss as well. Traditional methods of antimicrobial susceptibility test (AST) are usually time- consuming with poor quantification performance. As a result, there is a great demand for developing rapid and accurate AST techniques. In this paper, we present a promising new method towards this need. We developed a method to generate a composite hydrogel chip using a mixture of agar and alginate. We demonstrated rapid AST of three antibiotics (ampicillin, cefradine and gentamicin) using this device. Minimum inhibitory concentration (MIC) values of these antibiotics obtained were in accordance with the data from Clinical and Laboratory Standards Institute (CLSI). We also demonstrated convenient 2D AST on the device to study the performance of drug combinations.
What makes this method so appealing is the new idea to culture cells on top of a microfluidic chip rather than inside it; this allows users to operate and interpret the results using their experience on conventional plate culture, while incorporating the advantages of microfluidics without problems such as channel fouling and shear flow. Compared with conventional disk diffusion, our method provides much more information because of the linear gradient of drugs and drug combinations, and allows tracking the change in bacterial growth at single-cell level simultaneously at different concentrations of drugs and drug combinations, which greatly reduces the turnaround time of analysis. Moreover, our whole-hydrogel chip is inexpensive and bio-degradable, which are additional advantages for large-scale implementation.
