Optical Nanomotion Detection as a universal method for assessing life from rapid antimicrobial susceptibility testing to the search for extraterrestrial life
Year: 2026
Type: dissertation
Abstract: Life, whether studied in distant worlds as extraterrestrial life or in the context of infections on Earth, shows itself through nanoscale motion driven by metabolism and internal processes. This thesis explores a new way to detect living cells, without relying on complex biochemical tests. The method, called Optical Nanomotion Detection (ONMD), identifies viable cells by measuring their nanoscale vibrations that stop when a cell dies. Using a simple optical microscope to record these motions, ONMD can determine if microorganisms are alive and how they respond to antibiotics, all without the need for dyes, chemical markers, or relying on growth. The research validates ONMD as a practical and reliable technique for monitoring microbial vitality and viability on a single cell level. A custom microfluidic chip was developed to trap individual cells and keep them under observation while changing their environment. Experiments with yeast species such as Saccharomyces cerevisiae and Candida albicans showed that ONMD can quickly detect whether antifungal drugs are effective, distinguishing between living, inhibited, and dead cells in just a few hours, which is much faster comparing to conventional laboratory tests. The same approach also proved sensitive to gradual changes in cell health during cold storage of industrial Brewer’s yeast. Building on these results, ONMD was implemented on a portable, open-source optical platform, serving as a prototype for compact devices usable outside the laboratory. Tests on bacteria causing urinary tract infections confirmed that ONMD can rapidly identify antibiotic-resistant and susceptible strains. Finally, experiments with microorganisms that thrive in extreme environments, high radiation, salinity, alkalinity, or cold, demonstrated ONMD’s potential for detecting signs of life in conditions similar to those on Mars or icy moons. Together, these findings show that ONMD unites medicine and space science under a single idea: life can be recognized not only by its chemistry, but also by its motion.
Author: Radoničić, Vjera
Language: English
Subfield: Biophysics
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W7134103107