Optical tweezers for probing the interactions of ZnO and Ag nanoparticles with E. coli

• Published in: Archives of microbiology Vol. 206; no. 6; p. 243
• Main Authors: Hinge, Sarika B., Banpurkar, Arun G., Kulkarni, Gauri R.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.06.2024; Springer Nature B.V
• Subjects: Anti-Bacterial Agents - pharmacology; Antibacterial activity; Antiinfectives and antibacterials; Bacteria; Biochemistry; Biomedical and Life Sciences; Biotechnology; Cell Biology; Culture media; E coli; Ecology; Escherichia coli - drug effects; Escherichia coli - growth & development; Force measurement; Life Sciences; Mechanical properties; Metal Nanoparticles - chemistry; Microbial Ecology; Microbiology; Nanoparticles; Optical properties; Optical trapping; Optical Tweezers; Original Paper; Silver - chemistry; Silver - pharmacology; Trapping; Zinc oxide; Zinc Oxide - chemistry; Zinc Oxide - pharmacology; Nanoparticles; Antibacterial activity; Trapping stiffness; Optical force; E. coli
• ISSN: 0302-8933; 1432-072X
• DOI: 10.1007/s00203-024-03964-y

The antibacterial effect of nanoparticles is mainly studied on the ensembles of the bacteria. In contrast, the optical tweezer technique allows the investigation of similar effects on individual bacterium. E. coli is a self-propelled micro-swimmer and ATP-driven active microorganism. In this work, an optical tweezer is employed to examine the mechanical properties of E. coli incubated with ZnO and Ag nanoparticles (NP) in the growth medium. ZnO and Ag NP with a concentration of 10 µg/ml were dispersed in growth medium during active log-growth phase of E. coli . This E. coli- NP incubation is further continued for 12 h. The E. coli after incubation for 2 h, 6 h and 12 h were separately studied by the optical tweezer for their mechanical property. The IR laser ( λ  = 975 nm; power = 100 mW) was used for trapping the individual cells and estimated trapping force, trapping stiffness and corner frequency. The optical trapping force on E. coli incubated in nanoparticle suspension shows linear decreases with incubation time. This work brings the importance of optical trapping force measurement in probing the antibacterial stress due to nanoparticles on the individual bacterium. Graphical abstract