Researchers from Freiburg have developed a sensor platform that quantifies antibiotics in human blood within minutes
A team of researchers from the University of Freiburg has developed a system inspired by biology that can detect several different antibiotics in human blood or other fluids at the same time. This biosensor system could be used for medical diagnostics in the future, especially for point-of-care testing in doctors’ practices, on house calls and in pharmacies, as well as in environmental and food safety testing. The researchers focused their study on the antibiotics tetracycline and streptogramin in human blood. “The analysis takes only 10 minutes, from sample to result,” said the microsystems engineer Dr. Can Dincer, who is the head of the research team: “Our study was about demonstrating the applicability of the platform.” The researchers have recently published their results in Analytical Chemistry. Based on these findings, the group is currently working on developing a method to determine how quickly the human body breaks down antibiotics, thus enabling the dosage of medications to be adjusted to each patient. “This technology could pave the way for personalized antibiotic treatments in the future,” Dincer said.
The all-too-frequent use of antibiotics in human and veterinary medicine causes pathogens to develop resistance. Multidrug resistant bacteria are the reason for an increasing number of life-threatening infections that are difficult to treat with medications available today. In this context, biosensors have so much potential in research, since they are inexpensive and easy to work with. It is expected that biosensors can be employed to customize antibiotic treatments to fit each patient`s requirements, thereby decreasing the development of resistant bacteria in the future.
The electrochemical biosensor platform was developed by Prof. Dr. Gerald Urban’s research group. It works with extremely small amounts of liquid. “The major advantage of this system is that we can measure up to eight different substances at the same time, quickly and simply,” Dincer said. The researchers combined their chip technology with a method developed earlier by the bioengineering expert Prof. Dr. Wilfried Weber, also from the University of Freiburg. The method is based on a naturally occurring sensor protein in resistant bacteria to recognize antibiotics and activate their defence mechanisms. These bacterial sensors react quickly, sensitively and specifically to antibiotics, which makes them ideal for analytical testing. Essentially, the bacteria are providing the researchers with a tool that can be applied to fight them back in the long-run.
Learn more: Personalized antibiotic treatment
A new type of electronic sensor that might be used to quickly detect and classify bacteria for medical diagnostics and food safety has passed a key hurdle by distinguishing between dead and living bacteria cells.
Conventional laboratory technologies require that samples be cultured for hours or longer to grow enough of the bacteria for identification and analysis, for example, to determine which antibiotic to prescribe. The new approach might be used to create arrays of hundreds of sensors on an electronic chip, each sensor detecting a specific type of bacteria or pinpointing the effectiveness of particular antibiotics within minutes.
“We have taken a step toward this long-term goal by showing how to distinguish between live and dead bacteria,” said Muhammad Ashraful Alam, Purdue University’s Jai N. Gupta Professor of Electrical and Computer Engineering. “This is important because you need to be able to not only detect and identify bacteria, but to determine which antibiotics are effective in killing them.”
Findings are detailed in a research paper appearing this week in Proceedings of the National Academy of Sciences. The paper was authored by doctoral student Aida Ebrahimi and Alam. The droplet sensor evolved from a device originally designed to detect small concentrations of negatively charged DNA molecules in research that began about four years ago, Ebrahimi said.
“We did not anticipate that the sensor could be used to tell live and dead bacteria apart – it was a chance observation that eventually led us to this elegant way of measuring cell viability,” she said.