Nanomechanical Detection of Bacteria–Bacteriophage Interactions Using Microchannel Microcantilevers

Abstract

Multidrug-resistant (MDR) bacteria pose a serious threat to global health, which may be addressed using bacteriophage therapy. It is important to measure the susceptibility of bacteria to bacteriophages. We used a micromechanical sensor with a microfluidic channel for rapid antimicrobial susceptibility testing (AST). The interior surface of the microfluidic channel was functionalized with a molecule linker to capture the bacterial cells inside the channel. The Escherichia coli response to the bacteriophage PhiX174 and Staphylococcus aureus response to the bacteriophage Phi44AHJD is observed. The micromechanical sensor measured the mechanical fluctuations induced by nano-movements of the bacteria, reflecting their metabolic activity, before and after viral infection. In other words, the time-dependent oscillations of the microchannel can be correlated to the membrane movement in the cells produced by the cell metabolisms. The initial magnitudes of the fluctuations were different in the two bacteria. Bacteria exposure to the bacteriophages induced a sharp reduction of the sensor response, indicating a marked decrease in bacterial metabolic activities. In contrast to E. coli, S. aureus was resistant to Phi44AHJD, and the significant reduction in its metabolic activity may be attributed to transient dormancy due to stress caused by the viral interaction. This technique provides a rapid and accurate assessment of the susceptibility of bacteria to bacteriophages in a small volume of 150 picolitres.

Development of a microcantilever-based biosensor for detecting Programmed Death Ligand 1

“…In this system, a laser beam is focused on the free end of the microcantilever and the reflected beam is directed to a position sensitive detector (PSD). The system has been extensively discussed in details in ( Alzahrani et al, 2021 , Alzahrani et al, 2023a , Alzahrani et al, 2023b ). Arrays of microcantilevers, each consisting of eight identical cantilevers (500 μm long, 90 μm wide, and 1 μm thick) were purchased from Micromotive-company, Germany.…”

“…Microcantilever-based biosensors, renowned for their rapid response, high sensitivity, ease of use, and cost efficiency, are steadily gaining recognition across various detection fields ( Longo et al, 2013 , Gopinath et al, 2015 , Kim et al, 2015 , Alzahrani et al, 2021 , Alzahrani et al, 2023a , Alzahrani et al, 2023b ). They consist of tiny, flexible beams anchored at one end, leaving the opposite end free to come into contact with adjacent materials.…”

Review—Measurements of Ionizing Radiations Using Micromechanical Sensors

“…Micromechanical sensors, including microcantilevers, have high energy sensitivity, in order of femtojoules, 17 and they have been used in many physical, chemical and medical applications. 15,[17][18][19][20][21] Micromechanical sensors coated with various sensing layers (e.g. a polymer) absorb radiation, which causes the sensor either to bend or to undergo a resonance-frequency shift.…”