Miracles of microspheres: And now you can listen to what transpires between the cells in your body

By Syed Akbar
Hyderabad,: Scientists can now eavesdrop and listen to the
talks between different cells in the body.

Researchers from the city-based University of Hyderabad (UoH), and the
Indian Institute of Science Education and Research (IISER), Kolkata,
have used high power near-infrared laser light to secretly listen to
what transpires between the living cells. The research has great
medical significance, as it will provide an insight into the
happenings between health cells and killer cancerous cells.

The work was selected as a research highlight by the prestigious
science journal, Nature. Using high power near-infrared laser light,
the team trapped very small particles (microspheres) of polystyrene
beads. This could find use in probing the interactions between
biological cells. The minute particles that range between one milli
micron to 1000 milli micron were trapped in a tiny chamber formed by a
cover slip and a glass slide.

Prof. S Dutta Gupta of the School of Physics, University of Hyderabad,
formed part of the research team. Dr Ayan Banerjee from the department
of physical sciences, IISER-Kolkata, was the lead researcher.

"The ring pattern can be useful for studying tiny interaction forces
between micro-particles and the controllable study of biological
cell-to-cell interactions, such as that between cancer cells and
natural killer cells," said Dr Ayan Banerjee.

The Nature report said in recent years, focused laser beams have
emerged as handy tools for trapping and studying minute (micrometre)
materials. The tiny force exerted by such a beam induces random
self-assembly of micro-particles, thus providing an insight into the
dynamic of particles in a well-understood force environment.

“The researchers explored ordered self-assembly by employing a single
pure Gaussian beam emitted by a near-infrared laser. They used an
inverted microscope to focus the beam onto a sample chamber formed by
a cover slip and a glass slide. The sample chamber contained spherical
beads of polystyrene dispersed in water,” the research highlight
published in Nature said.

Slight manipulation of the microscope focus caused spherical
aberrations in the cover slip that pushed the beads towards the edge,
leading to the formation of well-defined closed ring structures.
Switching off the optical trap caused the beads to diffuse away, only
to reassemble almost instantaneously in the same ring structure after
the trap was switched on again.