June 05, 2026
Xiaolong Luo, Ph.D., and Zhaoyang Wang, Ph.D., both faculty members in the Department of Mechanical Engineering, have been awarded a $596,250 grant from the National Institutes of Health (NIH) National Institute of Allergy and Infectious Diseases (NIAID) for their research project, “A Rapid Antibiotic Susceptibility Testing (AST) Platform Using Multiplex Static Gradients.” This three-year NIH award follows a one-year, $59,514 grant from the Institute for Technology in Health Care (ITHC) for a pilot study on rapid AST for sepsis, awarded to Dr. Luo (left) and Dr. Wang (right) in January 2026.The series of projects shares the common goal of prototyping an innovative microfluidic reporting system that identifies effective antibiotics for acute bacterial infections, such as sepsis, within 30 minutes. Bacteria cause widespread diseases, including urinary tract infections, acute lung infections, and bloodstream infections. Prescriptions for treating acute bacterial infections are often empirical, relying on broad-spectrum antibiotics administered at high doses because the urgency of treatment does not permit waiting for laboratory test results, which may take hours or even days.
However, this practice risks ineffective treatment, disruption of the healthy microbiome, and, more significantly, the development of antibiotic resistance, which can limit the effectiveness of future antibiotic therapies when they are needed. Additionally, rapid assessment of microbial susceptibility to narrow-spectrum antibiotics is challenging because standard antimicrobial susceptibility testing (AST) takes two to three days and requires specialized facilities and trained personnel.
Instead of relying on bacterial growth analysis used in traditional AST, the team proposes prototyping a fast, precise AST platform to study and report on bacterial movement in real time. The approach is based on the observation that motile bacteria—the primary cause of common bacterial infections—swim away from antibiotic gradients and rapidly lose their motility when exposed to antibiotic concentrations sufficient to kill them. Through collaboration with John Choy, Ph.D. in the Department of Biology within the College of Arts and Sciences, the team is developing a rapid AST platform that integrates a robust microfluidic system with advanced image-processing techniques to monitor bacterial movement behaviors across multiplexed antibiotic gradients in real time, a phenomenon called bacterial chemotaxis.
“Amazingly, although bacteria are as small as one-hundredth the width of a human hair and do not have eyes to see or mouths to talk, they are remarkably intelligent. They can sense where food is located, detect toxic environments they should avoid, and determine what their fellow bacteria are doing so they can coordinate their efforts. That’s what we study inside engineered microdevices under a microscope,” Dr. Luo commented.
The rapid AST platform is expected to provide timely insights that enable physicians to prescribe personalized and effective treatments for acute bacterial infections.
“If successful, the rapid AST platform will significantly reduce wait times, cutting the turnaround from days for standard AST results to just 30 minutes for infections caused by motile cells,” said Dr. Wang.
In addition, for infections caused by non-motile bacteria, bacterial growth analysis can be performed within an hour using the multiplexed gradient platform—much faster than current AST methods—allowing physicians to issue a follow-up prescription when needed.
Moving forward, the researchers plan to integrate machine learning and artificial intelligence into the diagnosis and treatment of acute bacterial infections in future studies. Furthermore, this NIH grant will help train multiple undergraduate and graduate students in frontier research, inspiring and preparing them to pursue advanced research and development careers in the biomedical field.
This research program directly benefits public healthcare by enabling timely screening of effective drugs to treat acute bacterial infections such as sepsis, which accounts for one in every three hospital deaths in the United States. By accelerating the identification of effective treatments, this work has the potential to improve patient outcomes and reduce mortality in critical care settings. This project further underscores the College of Engineering, Physics, and Computing’s mission to advance knowledge and serve society through excellence in interdisciplinary research and innovation.