Researchers at the University of Zurich have succeeded in measuring the size and the electrical charge of nano particles by employing a unique method.
Cross-section through two chip-sized glass plates in which a nano particle is trapped in an energy hole (or “potential well” to use the scientific term). The colored fields show the different charges in the electrostatic field. The red zone signifies a very low charge, while the blue edges have a strong charge. (picture: UZH)
Electrical charge of nano particles plays an important role in fluid solutions as it prevents the fluid solution from becoming lumpy and also allows it to remain stable. Miniscule drops or particles are distributed in suspensions such as vaccines, pharmaceutical materials, paints, blood and milk. The newly developed method provides a complete picture of suspensions.
The researchers “enticed” the individual particles into an “electrostatic trap”. Thousands of round energy holes were created between two glass plates measuring the size of a chip. These energy holes possess a weak electrostatic charge. A drop of the solution was then added to the plates which led to the individual particles to fall into a hole and remain trapped. These particles move in a circular motion due to their collision with the solution’s molecules.
The electrical charges of nano particles play an important role in medicine. They can be used in drug-delivery systems to deliver medicines accurately over a long period. These nanoparticles transport the drugs to the specific location where they have to take effect. The electrical charge of the nano particles enables them to pass through the body’s tissue and cell membranes. The key role of electrical charge makes it important to be measured.
While previous tests have not provided precise measurements, the new method is able to measure the changes in electrical charge even of single entities and in real-time.
Prof. Madhavi Krishnan stated that changes in charge have an effect in proteins, DNA double helix, cell organelles and bodily reactions.