Washington, June 27 Scientists from the Max Planck Institute of Colloids and Interfaces have tailor-made nanoparticles that can be used as position lights on cell proteins and as light sources for display screens or for optical information technology in the future.
The researchers produced cadmium sulphide particles in microscopically small membrane bubbles.
Depending on which of the construction manuals they follow, the particles can be 4 or 50 nanometres in size.
Because the membrane bubbles have the same size as living cells, the scientists' work also provides an indication as to how nanostructures could arise in nature.
The scientists form bubbles that are around 50 micrometres in size from lecithin membranes, which are similar to biological membranes.
Like cells, membrane bubbles, or vesicles as scientists refer to them, also provide a closed reaction container.
The scientists load the membrane bubbles with one of two reactants for the nanoparticles. From this point, the researchers have developed two different sets of protocols.
In one case, they produce bubbles loaded with one of the two reactants, sodium sulphide or cadmium chloride.
The scientists then bring the bubbles with the different loads together and fuse two vesicles to form a bigger vesicle. This is done by subjecting the bubble cocktail to a short but very strong electrical pulse.
The electric shock fuses the membranes of two adjacent bubbles.
"Because the reactants are only present to a limited extent in the fused bubbles, the particles only grow to a size of four nanometers," explained Rumiana Dimova from the Max Planck Institute of Colloids and Interfaces.
The scientists were able to track the entire process directly under the microscope because they had added different fluorescent molecules to the membranes of the differently loaded vesicles.
The researchers were also able to see the nanoparticles forming as the particles shone like tiny lamps.
"With our method, we succeeded for the first time in producing particles with a certain diameter in vesicles whose size corresponds to that of cells," said Dimova. (ANI)
