Microbots: Micro-Swimmers

In Context 

• According to recent research, ‘Micro-swimmers’ may soon help with drug delivery.
• The research aims at moving microbots into the bloodstream to deliver drugs.
  • The technique makes use of light as a fuel to induce the tiny robots to move in simulations

About ‘Micro-swimmers’ 

• Made from the two-dimensional compound poly (heptazine imide) carbon nitride (aka PHI carbon nitride), these microbots are nothing like the miniaturised humans. 
• They range from 1-10 micrometre (a micrometre is one-millionth of a metre) in size, and can self-propel when energised by shining light.
• How do they swim across the blood?
  • The PHI carbon nitride microparticles are photocatalytic. 
  • Like in a solar cell, the incident light is converted into electrons and holes. These charges drive reactions in the surrounding liquid.
  •  The charges react with the fluid surrounding them. This reaction, combined with the particle’s electric field, makes the microbots (micro-swimmers) swim.
  • As long as there is light, electrons and holes are produced on the surface of the swimmers, which in turn react to form ions and an electric field around the swimmer. 
  • These ions move around the particle and cause fluid to flow around the particle. 
  • So this fluid flow causes the micro-swimmers to move.

Source:TH